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@bergwolf bergwolf commented Jun 5, 2013

Fix build errors reported by Stephen Rothwell.

Big change is patch 5 "staging/lustre/libcfs: cleanup linux-crypto" that removes Lustre private crc32 and crc32pclmul implementation. Those are simply copied from kernel implementation and isn't really necessary. Remove them and make CONFIG_LUSTRE_FS selects necessary crypto implementations.

Peng Tao (5):
staging/lustre: call set_cpus_allowed_ptr instead of set_cpus_allowed
staging/lustre: remove lu_context_keys_dump and lu_debugging_setup
staging/lustre/libcfs: restore LINVRNT
staging/lustre: surround module_refcount with CONFIG_MODULE_UNLOAD
staging/lustre/libcfs: cleanup linux-crypto

.../lustre/include/linux/libcfs/libcfs_private.h | 9 +
.../lustre/include/linux/libcfs/linux/linux-prim.h | 2 -
.../include/linux/libcfs/linux/portals_compat25.h | 2 -
drivers/staging/lustre/lustre/Kconfig | 18 +
drivers/staging/lustre/lustre/libcfs/Makefile | 5 +-
.../lustre/lustre/libcfs/crc32-pclmul_asm.S | 360 --------------------
.../staging/lustre/lustre/libcfs/linux/linux-cpu.c | 2 +-
.../lustre/libcfs/linux/linux-crypto-crc32.c | 149 --------
.../lustre/libcfs/linux/linux-crypto-crc32pclmul.c | 193 -----------
.../lustre/lustre/libcfs/linux/linux-crypto.c | 18 +-
drivers/staging/lustre/lustre/llite/llite_lib.c | 3 -
drivers/staging/lustre/lustre/obdclass/lu_object.c | 28 +--
drivers/staging/lustre/lustre/ptlrpc/ptlrpcd.c | 4 +-
13 files changed, 35 insertions(+), 758 deletions(-)

bergwolf added 5 commits June 5, 2013 16:34
set_cpus_allowed is not available with CONFIG_CPUMASK_OFFSTACK on.
We should call set_cpus_allowed_ptr instead.

Signed-off-by: Peng Tao <tao.peng@emc.com>
There are no callers of them. Besides, lu_context_keys_dump breaks
build when CONFIG_MODULES is not set.

Signed-off-by: Peng Tao <tao.peng@emc.com>
It was mistakenly removed by coan. Add it back and also with a new
Kconfig option to enable it.

Signed-off-by: Peng Tao <tao.peng@emc.com>
module_refcount() is not available when CONFIG_MODULE_UNLOAD is off.

Signed-off-by: Peng Tao <tao.peng@emc.com>
We don't need to implement crc32 and crc32pclmul on our own.
In fact, we just copied kernel's implementation. So drop it
and select kernel crypto in Kconfig.

Signed-off-by: Peng Tao <tao.peng@emc.com>
@bergwolf bergwolf closed this Jun 7, 2013
bergwolf pushed a commit that referenced this pull request Jul 1, 2013
Daniel Petre reported crashes in icmp_dst_unreach() with following call
graph:

#3 [ffff88003fc03938] __stack_chk_fail at ffffffff81037f77
#4 [ffff88003fc03948] icmp_send at ffffffff814d5fec
#5 [ffff88003fc03ae8] ipv4_link_failure at ffffffff814a1795
#6 [ffff88003fc03af8] ipgre_tunnel_xmit at ffffffff814e7965
#7 [ffff88003fc03b78] dev_hard_start_xmit at ffffffff8146e032
#8 [ffff88003fc03bc8] sch_direct_xmit at ffffffff81487d66
#9 [ffff88003fc03c08] __qdisc_run at ffffffff81487efd
#10 [ffff88003fc03c48] dev_queue_xmit at ffffffff8146e5a7
#11 [ffff88003fc03c88] ip_finish_output at ffffffff814ab596

Daniel found a similar problem mentioned in
 http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html

And indeed this is the root cause : skb->cb[] contains data fooling IP
stack.

We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure()
is called. Or else skb->cb[] might contain garbage from GSO segmentation
layer.

A similar fix was tested on linux-3.9, but gre code was refactored in
linux-3.10. I'll send patches for stable kernels as well.

Many thanks to Daniel for providing reports, patches and testing !

Reported-by: Daniel Petre <daniel.petre@rcs-rds.ro>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bergwolf pushed a commit that referenced this pull request Jul 10, 2013
…rnel/git/dhowells/linux-fs

Pull FS-Cache updates from David Howells:
 "This contains a number of fixes for various FS-Cache issues plus some
  cleanups.  The commits are, in order:

   1) Provide a system wait_on_atomic_t() and wake_up_atomic_t() sharing
      the bit-wait table (enhancement for #8).

   2) Don't put spin_lock() in a while-condition as spin_lock() may have
      a do {} while(0) wrapper (cleanup).

   3) Symbolically name i_mutex lock classes rather than using numbers
      in CacheFiles (cleanup).

   4) Don't sleep in page release if __GFP_FS is not set (deadlock vs
      ext4).

   5) Uninline fscache_object_init() (cleanup for #7).

   6) Wrap checks on object state (cleanup for #7).

   7) Simplify the object state machine by separating work states from
      wait states.

   8) Simplify cookie retention by objects (NULL pointer deref fix).

   9) Remove unused list_to_page() macro (cleanup).

  10) Make the remaining-pages counter in the retrieval op atomic
      (assertion failure fix).

  11) Don't use spin_is_locked() in assertions (assertion failure fix)"

* tag 'fscache-20130702' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  FS-Cache: Don't use spin_is_locked() in assertions
  FS-Cache: The retrieval remaining-pages counter needs to be atomic_t
  cachefiles: remove unused macro list_to_page()
  FS-Cache: Simplify cookie retention for fscache_objects, fixing oops
  FS-Cache: Fix object state machine to have separate work and wait states
  FS-Cache: Wrap checks on object state
  FS-Cache: Uninline fscache_object_init()
  FS-Cache: Don't sleep in page release if __GFP_FS is not set
  CacheFiles: name i_mutex lock class explicitly
  fs/fscache: remove spin_lock() from the condition in while()
  Add wait_on_atomic_t() and wake_up_atomic_t()
bergwolf pushed a commit that referenced this pull request Jul 10, 2013
Several people reported the warning: "kernel BUG at kernel/timer.c:729!"
and the stack trace is:

	#7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905
	#8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at ffffffffa0731d25 [bridge]
	#9 [ffff880214d25c80] br_multicast_disable_port+88 at ffffffffa0732948 [bridge]
	#10 [ffff880214d25cb0] br_stp_disable_port+154 at ffffffffa072bcca [bridge]
	#11 [ffff880214d25ce8] br_device_event+520 at ffffffffa072a4e8 [bridge]
	#12 [ffff880214d25d18] notifier_call_chain+76 at ffffffff8164aafc
	#13 [ffff880214d25d50] raw_notifier_call_chain+22 at ffffffff810858f6
	#14 [ffff880214d25d60] call_netdevice_notifiers+45 at ffffffff81536aad
	#15 [ffff880214d25d80] dev_close_many+183 at ffffffff81536d17
	#16 [ffff880214d25dc0] rollback_registered_many+168 at ffffffff81537f68
	#17 [ffff880214d25de8] rollback_registered+49 at ffffffff81538101
	#18 [ffff880214d25e10] unregister_netdevice_queue+72 at ffffffff815390d8
	#19 [ffff880214d25e30] __tun_detach+272 at ffffffffa074c2f0 [tun]
	#20 [ffff880214d25e88] tun_chr_close+45 at ffffffffa074c4bd [tun]
	#21 [ffff880214d25ea8] __fput+225 at ffffffff8119b1f1
	#22 [ffff880214d25ef0] ____fput+14 at ffffffff8119b3fe
	#23 [ffff880214d25f00] task_work_run+159 at ffffffff8107cf7f
	#24 [ffff880214d25f30] do_notify_resume+97 at ffffffff810139e1
	#25 [ffff880214d25f50] int_signal+18 at ffffffff8164f292

this is due to I forgot to check if mp->timer is armed in
br_multicast_del_pg(). This bug is introduced by
commit 9f00b2e (bridge: only expire the mdb entry
when query is received).

Same for __br_mdb_del().

Tested-by: poma <pomidorabelisima@gmail.com>
Reported-by: LiYonghua <809674045@qq.com>
Reported-by: Robert Hancock <hancockrwd@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bergwolf pushed a commit that referenced this pull request Aug 6, 2013
We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped.  This is
actually unnecessary, and resulted in buggy behaviour:

1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one

This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).

This behaviour resulted in a warning message like this one:

-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'

Call Trace:
 [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0
 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
 [<ffffffff812734b4>] ? kobject_add+0x44/0x70
 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
 [<ffffffff8134b389>] ? device_add+0xc9/0x650

-------------------8<---------------------------------------

Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers.  Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.

This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:

-------------------8<---------------------------------------
PID: 6162   TASK: ffff8801147ad500  CPU: 0   COMMAND: "cat"
 #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
 #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b
 #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
    [exception RIP: strlen+2]
    RIP: ffffffff81272ae2  RSP: ffff88011b9d5d00  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff880118901c18  RCX: 0000000000000000
    RDX: ffff88011799982c  RSI: 00000000000000d0  RDI: 3a303030302f3030
    RBP: ffff88011b9d5d38   R8: 0000000000000006   R9: ffffffffa0134500
    R10: 0000000000001000  R11: 0000000000001000  R12: ffff880117a1cc10
    R13: 00000000000000d0  R14: 0000000000000017  R15: ffffffff81aff700
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
 #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
 #9 [ffff88011b9d5de0] device_del at ffffffff813440c7

-------------------8<---------------------------------------

So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.

CC: <stable@vger.kernel.org>
Reported-by: chayang <chayang@redhat.com>
Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com>
Reported-by: FuXiangChun <xfu@redhat.com>
Reported-by: Qunfang Zhang <qzhang@redhat.com>
Reported-by: Sibiao Luo <sluo@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
bergwolf pushed a commit that referenced this pull request Oct 14, 2013
In several places, this snippet is used when removing neigh entries:

	list_del(&neigh->list);
	ipoib_neigh_free(neigh);

The list_del() removes neigh from the associated struct ipoib_path, while
ipoib_neigh_free() removes neigh from the device's neigh entry lookup
table.  Both of these operations are protected by the priv->lock
spinlock.  The table however is also protected via RCU, and so naturally
the lock is not held when doing reads.

This leads to a race condition, in which a thread may successfully look
up a neigh entry that has already been deleted from neigh->list.  Since
the previous deletion will have marked the entry with poison, a second
list_del() on the object will cause a panic:

  #5 [ffff8802338c3c70] general_protection at ffffffff815108c5
     [exception RIP: list_del+16]
     RIP: ffffffff81289020  RSP: ffff8802338c3d20  RFLAGS: 00010082
     RAX: dead000000200200  RBX: ffff880433e60c88  RCX: 0000000000009e6c
     RDX: 0000000000000246  RSI: ffff8806012ca298  RDI: ffff880433e60c88
     RBP: ffff8802338c3d30   R8: ffff8806012ca2e8   R9: 00000000ffffffff
     R10: 0000000000000001  R11: 0000000000000000  R12: ffff8804346b2020
     R13: ffff88032a3e7540  R14: ffff8804346b26e0  R15: 0000000000000246
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  #6 [ffff8802338c3d38] ipoib_cm_tx_handler at ffffffffa066fe0a [ib_ipoib]
  #7 [ffff8802338c3d98] cm_process_work at ffffffffa05149a7 [ib_cm]
  #8 [ffff8802338c3de8] cm_work_handler at ffffffffa05161aa [ib_cm]
  #9 [ffff8802338c3e38] worker_thread at ffffffff81090e10
 #10 [ffff8802338c3ee8] kthread at ffffffff81096c66
 #11 [ffff8802338c3f48] kernel_thread at ffffffff8100c0ca

We move the list_del() into ipoib_neigh_free(), so that deletion happens
only once, after the entry has been successfully removed from the lookup
table.  This same behavior is already used in ipoib_del_neighs_by_gid()
and __ipoib_reap_neigh().

Signed-off-by: Jim Foraker <foraker1@llnl.gov>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Reviewed-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
bergwolf pushed a commit that referenced this pull request Oct 14, 2013
On OMAP4 we have clk_set_rate()s being done for a few
DPLL clock nodes, as part of the clock init code, since
the bootloaders no longer locks these DPLLs.

So we have a clk_set_rate() done for a ABE DPLL node (which
inturn locks it) followed by a clk_set_rate() for the USB DPLL.

With USB DPLL being in bypass, we have this parent->child
relationship thats formed while the clocks get registered.

dpll_abe_ck
    |
    V
dpll_abe_x2_ck
    |
    V
dpll_abe_m3x2_ck
    |
    V
usb_hs_clk_div_ck
    |
    V
dpll_usb_ck

This is because usb_hs_clk_div_ck is bypass clock for dpll_usb_ck.

So with this parent->child relationship in place, a clk_set_rate()
on ABE DPLL results eventually in a clk_set_rate() call on USB DPLL,
because CCF does a clk_change_rate() (as part of clk_set_rate()) on
all downstream clocks resulting from a rate change on the top clock.

So its important that we lock USB DPLL before we lock ABE DPLL.
Without which we see these error logs at boot.
[These error logs will not be seen if using a bootloader that locks
USB DPLL]

[    0.000000] clock: dpll_usb_ck failed transition to 'locked'
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] Division by zero in kernel.
[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-03445-gfb2af00-dirty #7
[    0.000000] [<c001bfe8>] (unwind_backtrace+0x0/0xf4) from [<c001868c>] (show_stack+0x10/0x14)
[    0.000000] [<c001868c>] (show_stack+0x10/0x14) from [<c02deb28>] (Ldiv0+0x8/0x10)
[    0.000000] [<c02deb28>] (Ldiv0+0x8/0x10) from [<c0477030>] (clk_divider_set_rate+0x10/0x114)
[    0.000000] [<c0477030>] (clk_divider_set_rate+0x10/0x114) from [<c0476ef4>] (clk_change_rate+0x38/0xb8)
[    0.000000] [<c0476ef4>] (clk_change_rate+0x38/0xb8) from [<c0476f5c>] (clk_change_rate+0xa0/0xb8)
[    0.000000] clock: trace_clk_div_ck: could not find divisor for target rate 0 for parent pmd_trace_clk_mux_ck
[    0.000000] Division by zero in kernel.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
bergwolf pushed a commit that referenced this pull request Oct 14, 2013
When booting secondary CPUs, announce_cpu() is called to show which cpu has
been brought up. For example:

[    0.402751] smpboot: Booting Node   0, Processors  #1 #2 #3 #4 #5 OK
[    0.525667] smpboot: Booting Node   1, Processors  #6 #7 #8 #9 #10 #11 OK
[    0.755592] smpboot: Booting Node   0, Processors  #12 #13 #14 #15 #16 #17 OK
[    0.890495] smpboot: Booting Node   1, Processors  #18 #19 #20 #21 #22 #23

But the last "OK" is lost, because 'nr_cpu_ids-1' represents the maximum
possible cpu id. It should use the maximum present cpu id in case not all
CPUs booted up.

Signed-off-by: Libin <huawei.libin@huawei.com>
Cc: <guohanjun@huawei.com>
Cc: <wangyijing@huawei.com>
Cc: <fenghua.yu@intel.com>
Cc: <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1378378676-18276-1-git-send-email-huawei.libin@huawei.com
[ tweaked the changelog, removed unnecessary line break, tweaked the format to align the fields vertically. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
bergwolf pushed a commit that referenced this pull request Oct 14, 2013
When parsing lines from objdump a line containing source code starting
with a numeric label is mistaken for a line of disassembly starting with
a memory address.

Current validation fails to recognise that the "memory address" is out
of range and calculates an invalid offset which later causes this
segfault:

Program received signal SIGSEGV, Segmentation fault.
0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50)
    at util/annotate.c:631
631				hits += h->addr[offset++];
(gdb) bt
 #0  0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50)
    at util/annotate.c:631
 #1  0x00000000004d65e3 in annotate_browser__calc_percent (browser=0x7fffffffd130, evsel=0xa01da0) at ui/browsers/annotate.c:364
 #2  0x00000000004d7433 in annotate_browser__run (browser=0x7fffffffd130, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:672
 #3  0x00000000004d80c9 in symbol__tui_annotate (sym=0xc989a0, map=0xa02660, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:962
 #4  0x00000000004d7aa0 in hist_entry__tui_annotate (he=0xdf73f0, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:823
 #5  0x00000000004dd648 in perf_evsel__hists_browse (evsel=0xa01da0, nr_events=1, helpline=
    0x58b768 "For a higher level overview, try: perf report --sort comm,dso", ev_name=0xa02cd0 "cycles", left_exits=false, hbt=
    0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1659
 #6  0x00000000004de372 in perf_evlist__tui_browse_hists (evlist=0xa01520, help=
    0x58b768 "For a higher level overview, try: perf report --sort comm,dso", hbt=0x0, min_pcnt=0, env=0xa011e0)
    at ui/browsers/hists.c:1950
 #7  0x000000000042cf6b in __cmd_report (rep=0x7fffffffd6c0) at builtin-report.c:581
 #8  0x000000000042e25d in cmd_report (argc=0, argv=0x7fffffffe4b0, prefix=0x0) at builtin-report.c:965
 #9  0x000000000041a0e1 in run_builtin (p=0x801548, argc=1, argv=0x7fffffffe4b0) at perf.c:319
 #10 0x000000000041a319 in handle_internal_command (argc=1, argv=0x7fffffffe4b0) at perf.c:376
 #11 0x000000000041a465 in run_argv (argcp=0x7fffffffe38c, argv=0x7fffffffe380) at perf.c:420
 #12 0x000000000041a707 in main (argc=1, argv=0x7fffffffe4b0) at perf.c:521

After the fix is applied the symbol can be annotated showing the
problematic line "1:      rep"

copy_user_generic_string  /usr/lib/debug/lib/modules/3.9.10-100.fc17.x86_64/vmlinux
             */
            ENTRY(copy_user_generic_string)
                    CFI_STARTPROC
                    ASM_STAC
                    andl %edx,%edx
              and    %edx,%edx
                    jz 4f
              je     37
                    cmpl $8,%edx
              cmp    $0x8,%edx
                    jb 2f           /* less than 8 bytes, go to byte copy loop */
              jb     33
                    ALIGN_DESTINATION
              mov    %edi,%ecx
              and    $0x7,%ecx
              je     28
              sub    $0x8,%ecx
              neg    %ecx
              sub    %ecx,%edx
        1a:   mov    (%rsi),%al
              mov    %al,(%rdi)
              inc    %rsi
              inc    %rdi
              dec    %ecx
              jne    1a
                    movl %edx,%ecx
        28:   mov    %edx,%ecx
                    shrl $3,%ecx
              shr    $0x3,%ecx
                    andl $7,%edx
              and    $0x7,%edx
            1:      rep
100.00        rep    movsq %ds:(%rsi),%es:(%rdi)
                    movsq
            2:      movl %edx,%ecx
        33:   mov    %edx,%ecx
            3:      rep
              rep    movsb %ds:(%rsi),%es:(%rdi)
                    movsb
            4:      xorl %eax,%eax
        37:   xor    %eax,%eax
              data32 xchg %ax,%ax
                    ASM_CLAC
                    ret
              retq

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1379009721-27667-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
bergwolf pushed a commit that referenced this pull request Nov 22, 2013
…ux/kernel/git/tip/tip

Pull x86 boot changes from Ingo Molnar:
 "Two changes that prettify and compactify the SMP bootup output from:

     smpboot: Booting Node   0, Processors  #1 #2 #3 OK
     smpboot: Booting Node   1, Processors  #4 #5 #6 #7 OK
     smpboot: Booting Node   2, Processors  #8 #9 #10 #11 OK
     smpboot: Booting Node   3, Processors  #12 #13 #14 #15 OK
     Brought up 16 CPUs

  to something like:

     x86: Booting SMP configuration:
     .... node  #0, CPUs:        #1  #2  #3
     .... node  #1, CPUs:    #4  #5  #6  #7
     .... node  #2, CPUs:    #8  #9 #10 #11
     .... node  #3, CPUs:   #12 #13 #14 #15
     x86: Booted up 4 nodes, 16 CPUs"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Further compress CPUs bootup message
  x86: Improve the printout of the SMP bootup CPU table
bergwolf pushed a commit that referenced this pull request Dec 3, 2013
Commit 8c4f3c3 "ftrace: Check module functions being traced on reload"
fixed module loading and unloading with respect to function tracing, but
it missed the function graph tracer. If you perform the following

 # cd /sys/kernel/debug/tracing
 # echo function_graph > current_tracer
 # modprobe nfsd
 # echo nop > current_tracer

You'll get the following oops message:

 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 2910 at /linux.git/kernel/trace/ftrace.c:1640 __ftrace_hash_rec_update.part.35+0x168/0x1b9()
 Modules linked in: nfsd exportfs nfs_acl lockd ipt_MASQUERADE sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables uinput snd_hda_codec_idt
 CPU: 2 PID: 2910 Comm: bash Not tainted 3.13.0-rc1-test #7
 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
  0000000000000668 ffff8800787efcf8 ffffffff814fe193 ffff88007d500000
  0000000000000000 ffff8800787efd38 ffffffff8103b80a 0000000000000668
  ffffffff810b2b9a ffffffff81a48370 0000000000000001 ffff880037aea000
 Call Trace:
  [<ffffffff814fe193>] dump_stack+0x4f/0x7c
  [<ffffffff8103b80a>] warn_slowpath_common+0x81/0x9b
  [<ffffffff810b2b9a>] ? __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [<ffffffff8103b83e>] warn_slowpath_null+0x1a/0x1c
  [<ffffffff810b2b9a>] __ftrace_hash_rec_update.part.35+0x168/0x1b9
  [<ffffffff81502f89>] ? __mutex_lock_slowpath+0x364/0x364
  [<ffffffff810b2cc2>] ftrace_shutdown+0xd7/0x12b
  [<ffffffff810b47f0>] unregister_ftrace_graph+0x49/0x78
  [<ffffffff810c4b30>] graph_trace_reset+0xe/0x10
  [<ffffffff810bf393>] tracing_set_tracer+0xa7/0x26a
  [<ffffffff810bf5e1>] tracing_set_trace_write+0x8b/0xbd
  [<ffffffff810c501c>] ? ftrace_return_to_handler+0xb2/0xde
  [<ffffffff811240a8>] ? __sb_end_write+0x5e/0x5e
  [<ffffffff81122aed>] vfs_write+0xab/0xf6
  [<ffffffff8150a185>] ftrace_graph_caller+0x85/0x85
  [<ffffffff81122dbd>] SyS_write+0x59/0x82
  [<ffffffff8150a185>] ftrace_graph_caller+0x85/0x85
  [<ffffffff8150a2d2>] system_call_fastpath+0x16/0x1b
 ---[ end trace 940358030751eafb ]---

The above mentioned commit didn't go far enough. Well, it covered the
function tracer by adding checks in __register_ftrace_function(). The
problem is that the function graph tracer circumvents that (for a slight
efficiency gain when function graph trace is running with a function
tracer. The gain was not worth this).

The problem came with ftrace_startup() which should always be called after
__register_ftrace_function(), if you want this bug to be completely fixed.

Anyway, this solution moves __register_ftrace_function() inside of
ftrace_startup() and removes the need to call them both.

Reported-by: Dave Wysochanski <dwysocha@redhat.com>
Fixes: ed926f9 ("ftrace: Use counters to enable functions to trace")
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
bergwolf pushed a commit that referenced this pull request Mar 4, 2014
Currently, update_note_header_size_elf64() and
update_note_header_size_elf32() will add the size of a PT_NOTE entry to
real_sz even if that causes real_sz to exceeds max_sz.  This patch
corrects the while loop logic in those routines to ensure that does not
happen and prints a warning if a PT_NOTE entry is dropped.  If zero
PT_NOTE entries are found or this condition is encountered because the
only entry was dropped, a warning is printed and an error is returned.

One possible negative side effect of exceeding the max_sz limit is an
allocation failure in merge_note_headers_elf64() or
merge_note_headers_elf32() which would produce console output such as
the following while booting the crash kernel.

  vmalloc: allocation failure: 14076997632 bytes
  swapper/0: page allocation failure: order:0, mode:0x80d2
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-gbp1 #7
  Call Trace:
    dump_stack+0x19/0x1b
    warn_alloc_failed+0xf0/0x160
    __vmalloc_node_range+0x19e/0x250
    vmalloc_user+0x4c/0x70
    merge_note_headers_elf64.constprop.9+0x116/0x24a
    vmcore_init+0x2d4/0x76c
    do_one_initcall+0xe2/0x190
    kernel_init_freeable+0x17c/0x207
    kernel_init+0xe/0x180
    ret_from_fork+0x7c/0xb0

  Kdump: vmcore not initialized

  kdump: dump target is /dev/sda4
  kdump: saving to /sysroot//var/crash/127.0.0.1-2014.01.28-13:58:52/
  kdump: saving vmcore-dmesg.txt
  Cannot open /proc/vmcore: No such file or directory
  kdump: saving vmcore-dmesg.txt failed
  kdump: saving vmcore
  kdump: saving vmcore failed

This type of failure has been seen on a four socket prototype system
with certain memory configurations.  Most PT_NOTE sections have a single
entry similar to:

  n_namesz = 0x5
  n_descsz = 0x150
  n_type   = 0x1

Occasionally, a second entry is encountered with very large n_namesz and
n_descsz sizes:

  n_namesz = 0x80000008
  n_descsz = 0x510ae163
  n_type   = 0x80000008

Not yet sure of the source of these extra entries, they seem bogus, but
they shouldn't cause crash dump to fail.

Signed-off-by: Greg Pearson <greg.pearson@hp.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bergwolf pushed a commit that referenced this pull request Mar 18, 2014
vmxnet3's netpoll driver is incorrectly coded.  It directly calls
vmxnet3_do_poll, which is the driver internal napi poll routine.  As the netpoll
controller method doesn't block real napi polls in any way, there is a potential
for race conditions in which the netpoll controller method and the napi poll
method run concurrently.  The result is data corruption causing panics such as this
one recently observed:
PID: 1371   TASK: ffff88023762caa0  CPU: 1   COMMAND: "rs:main Q:Reg"
 #0 [ffff88023abd5780] machine_kexec at ffffffff81038f3b
 #1 [ffff88023abd57e0] crash_kexec at ffffffff810c5d92
 #2 [ffff88023abd58b0] oops_end at ffffffff8152b570
 #3 [ffff88023abd58e0] die at ffffffff81010e0b
 #4 [ffff88023abd5910] do_trap at ffffffff8152add4
 #5 [ffff88023abd5970] do_invalid_op at ffffffff8100cf95
 #6 [ffff88023abd5a10] invalid_op at ffffffff8100bf9b
    [exception RIP: vmxnet3_rq_rx_complete+1968]
    RIP: ffffffffa00f1e80  RSP: ffff88023abd5ac8  RFLAGS: 00010086
    RAX: 0000000000000000  RBX: ffff88023b5dcee0  RCX: 00000000000000c0
    RDX: 0000000000000000  RSI: 00000000000005f2  RDI: ffff88023b5dcee0
    RBP: ffff88023abd5b48   R8: 0000000000000000   R9: ffff88023a3b6048
    R10: 0000000000000000  R11: 0000000000000002  R12: ffff8802398d4cd8
    R13: ffff88023af35140  R14: ffff88023b60c890  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffff88023abd5b50] vmxnet3_do_poll at ffffffffa00f204a [vmxnet3]
 #8 [ffff88023abd5b80] vmxnet3_netpoll at ffffffffa00f209c [vmxnet3]
 #9 [ffff88023abd5ba0] netpoll_poll_dev at ffffffff81472bb7

The fix is to do as other drivers do, and have the poll controller call the top
half interrupt handler, which schedules a napi poll properly to recieve frames

Tested by myself, successfully.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Shreyas Bhatewara <sbhatewara@vmware.com>
CC: "VMware, Inc." <pv-drivers@vmware.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: stable@vger.kernel.org
Reviewed-by: Shreyas N Bhatewara <sbhatewara@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bergwolf pushed a commit that referenced this pull request May 4, 2016
commit ec183d2 upstream.

Fixes segmentation fault using, for instance:

  (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls
  Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64
  [Thread debugging using libthread_db enabled]
  Using host libthread_db library "/lib64/libthread_db.so.1".

 Program received signal SIGSEGV, Segmentation fault.
  0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  (gdb) bt
  #0  0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410
  #1  0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:433
  #2  0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:498
  #3  0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0)
      at util/parse-events.c:936
  #4  0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391
  #5  0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361
  #6  0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401
  #7  0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253
  #8  0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364
  #9  0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664
  #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539
  #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264
  #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390
  #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451
  #14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495
  #15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618
(gdb)

Intel PT attempts to find the sched:sched_switch tracepoint but that seg
faults if tracefs is not readable, because the error reporting structure
is null, as errors are not reported when automatically adding
tracepoints.  Fix by checking before using.

Committer note:

This doesn't take place in a kernel that supports
perf_event_attr.context_switch, that is the default way that will be
used for tracking context switches, only in older kernels, like 4.2, in
a machine with Intel PT (e.g. Broadwell) for non-priviledged users.

Further info from a similar patch by Wang:

The error is in tracepoint_error: it assumes the 'e' parameter is valid.

However, there are many situation a parse_event() can be called without
parse_events_error. See result of

  $ grep 'parse_events(.*NULL)' ./tools/perf/ -r'

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Tong Zhang <ztong@vt.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output")
Link: http://lkml.kernel.org/r/1453809921-24596-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request May 4, 2016
commit 17e4bce upstream.

Ubsan reports the following warning due to a typo in
update_accessed_dirty_bits template, the patch fixes
the typo:

[  168.791851] ================================================================================
[  168.791862] UBSAN: Undefined behaviour in arch/x86/kvm/paging_tmpl.h:252:15
[  168.791866] index 4 is out of range for type 'u64 [4]'
[  168.791871] CPU: 0 PID: 2950 Comm: qemu-system-x86 Tainted: G           O L  4.5.0-rc5-next-20160222 #7
[  168.791873] Hardware name: LENOVO 23205NG/23205NG, BIOS G2ET95WW (2.55 ) 07/09/2013
[  168.791876]  0000000000000000 ffff8801cfcaf208 ffffffff81c9f780 0000000041b58ab3
[  168.791882]  ffffffff82eb2cc1 ffffffff81c9f6b4 ffff8801cfcaf230 ffff8801cfcaf1e0
[  168.791886]  0000000000000004 0000000000000001 0000000000000000 ffffffffa1981600
[  168.791891] Call Trace:
[  168.791899]  [<ffffffff81c9f780>] dump_stack+0xcc/0x12c
[  168.791904]  [<ffffffff81c9f6b4>] ? _atomic_dec_and_lock+0xc4/0xc4
[  168.791910]  [<ffffffff81da9e81>] ubsan_epilogue+0xd/0x8a
[  168.791914]  [<ffffffff81daafa2>] __ubsan_handle_out_of_bounds+0x15c/0x1a3
[  168.791918]  [<ffffffff81daae46>] ? __ubsan_handle_shift_out_of_bounds+0x2bd/0x2bd
[  168.791922]  [<ffffffff811287ef>] ? get_user_pages_fast+0x2bf/0x360
[  168.791954]  [<ffffffffa1794050>] ? kvm_largepages_enabled+0x30/0x30 [kvm]
[  168.791958]  [<ffffffff81128530>] ? __get_user_pages_fast+0x360/0x360
[  168.791987]  [<ffffffffa181b818>] paging64_walk_addr_generic+0x1b28/0x2600 [kvm]
[  168.792014]  [<ffffffffa1819cf0>] ? init_kvm_mmu+0x1100/0x1100 [kvm]
[  168.792019]  [<ffffffff8129e350>] ? debug_check_no_locks_freed+0x350/0x350
[  168.792044]  [<ffffffffa1819cf0>] ? init_kvm_mmu+0x1100/0x1100 [kvm]
[  168.792076]  [<ffffffffa181c36d>] paging64_gva_to_gpa+0x7d/0x110 [kvm]
[  168.792121]  [<ffffffffa181c2f0>] ? paging64_walk_addr_generic+0x2600/0x2600 [kvm]
[  168.792130]  [<ffffffff812e848b>] ? debug_lockdep_rcu_enabled+0x7b/0x90
[  168.792178]  [<ffffffffa17d9a4a>] emulator_read_write_onepage+0x27a/0x1150 [kvm]
[  168.792208]  [<ffffffffa1794d44>] ? __kvm_read_guest_page+0x54/0x70 [kvm]
[  168.792234]  [<ffffffffa17d97d0>] ? kvm_task_switch+0x160/0x160 [kvm]
[  168.792238]  [<ffffffff812e848b>] ? debug_lockdep_rcu_enabled+0x7b/0x90
[  168.792263]  [<ffffffffa17daa07>] emulator_read_write+0xe7/0x6d0 [kvm]
[  168.792290]  [<ffffffffa183b620>] ? em_cr_write+0x230/0x230 [kvm]
[  168.792314]  [<ffffffffa17db005>] emulator_write_emulated+0x15/0x20 [kvm]
[  168.792340]  [<ffffffffa18465f8>] segmented_write+0xf8/0x130 [kvm]
[  168.792367]  [<ffffffffa1846500>] ? em_lgdt+0x20/0x20 [kvm]
[  168.792374]  [<ffffffffa14db512>] ? vmx_read_guest_seg_ar+0x42/0x1e0 [kvm_intel]
[  168.792400]  [<ffffffffa1846d82>] writeback+0x3f2/0x700 [kvm]
[  168.792424]  [<ffffffffa1846990>] ? em_sidt+0xa0/0xa0 [kvm]
[  168.792449]  [<ffffffffa185554d>] ? x86_decode_insn+0x1b3d/0x4f70 [kvm]
[  168.792474]  [<ffffffffa1859032>] x86_emulate_insn+0x572/0x3010 [kvm]
[  168.792499]  [<ffffffffa17e71dd>] x86_emulate_instruction+0x3bd/0x2110 [kvm]
[  168.792524]  [<ffffffffa17e6e20>] ? reexecute_instruction.part.110+0x2e0/0x2e0 [kvm]
[  168.792532]  [<ffffffffa14e9a81>] handle_ept_misconfig+0x61/0x460 [kvm_intel]
[  168.792539]  [<ffffffffa14e9a20>] ? handle_pause+0x450/0x450 [kvm_intel]
[  168.792546]  [<ffffffffa15130ea>] vmx_handle_exit+0xd6a/0x1ad0 [kvm_intel]
[  168.792572]  [<ffffffffa17f6a6c>] ? kvm_arch_vcpu_ioctl_run+0xbdc/0x6090 [kvm]
[  168.792597]  [<ffffffffa17f6bcd>] kvm_arch_vcpu_ioctl_run+0xd3d/0x6090 [kvm]
[  168.792621]  [<ffffffffa17f6a6c>] ? kvm_arch_vcpu_ioctl_run+0xbdc/0x6090 [kvm]
[  168.792627]  [<ffffffff8293b530>] ? __ww_mutex_lock_interruptible+0x1630/0x1630
[  168.792651]  [<ffffffffa17f5e90>] ? kvm_arch_vcpu_runnable+0x4f0/0x4f0 [kvm]
[  168.792656]  [<ffffffff811eeb30>] ? preempt_notifier_unregister+0x190/0x190
[  168.792681]  [<ffffffffa17e0447>] ? kvm_arch_vcpu_load+0x127/0x650 [kvm]
[  168.792704]  [<ffffffffa178e9a3>] kvm_vcpu_ioctl+0x553/0xda0 [kvm]
[  168.792727]  [<ffffffffa178e450>] ? vcpu_put+0x40/0x40 [kvm]
[  168.792732]  [<ffffffff8129e350>] ? debug_check_no_locks_freed+0x350/0x350
[  168.792735]  [<ffffffff82946087>] ? _raw_spin_unlock+0x27/0x40
[  168.792740]  [<ffffffff8163a943>] ? handle_mm_fault+0x1673/0x2e40
[  168.792744]  [<ffffffff8129daa8>] ? trace_hardirqs_on_caller+0x478/0x6c0
[  168.792747]  [<ffffffff8129dcfd>] ? trace_hardirqs_on+0xd/0x10
[  168.792751]  [<ffffffff812e848b>] ? debug_lockdep_rcu_enabled+0x7b/0x90
[  168.792756]  [<ffffffff81725a80>] do_vfs_ioctl+0x1b0/0x12b0
[  168.792759]  [<ffffffff817258d0>] ? ioctl_preallocate+0x210/0x210
[  168.792763]  [<ffffffff8174aef3>] ? __fget+0x273/0x4a0
[  168.792766]  [<ffffffff8174acd0>] ? __fget+0x50/0x4a0
[  168.792770]  [<ffffffff8174b1f6>] ? __fget_light+0x96/0x2b0
[  168.792773]  [<ffffffff81726bf9>] SyS_ioctl+0x79/0x90
[  168.792777]  [<ffffffff82946880>] entry_SYSCALL_64_fastpath+0x23/0xc1
[  168.792780] ================================================================================

Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com>
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request Dec 7, 2016
commit 420902c upstream.

If we hold the superblock lock while calling reiserfs_quota_on_mount(), we can
deadlock our own worker - mount blocks kworker/3:2, sleeps forever more.

crash> ps|grep UN
    715      2   3  ffff880220734d30  UN   0.0       0      0  [kworker/3:2]
   9369   9341   2  ffff88021ffb7560  UN   1.3  493404 123184  Xorg
   9665   9664   3  ffff880225b92ab0  UN   0.0   47368    812  udisks-daemon
  10635  10403   3  ffff880222f22c70  UN   0.0   14904    936  mount
crash> bt ffff880220734d30
PID: 715    TASK: ffff880220734d30  CPU: 3   COMMAND: "kworker/3:2"
 #0 [ffff8802244c3c20] schedule at ffffffff8144584b
 #1 [ffff8802244c3cc8] __rt_mutex_slowlock at ffffffff814472b3
 #2 [ffff8802244c3d28] rt_mutex_slowlock at ffffffff814473f5
 #3 [ffff8802244c3dc8] reiserfs_write_lock at ffffffffa05f28fd [reiserfs]
 #4 [ffff8802244c3de8] flush_async_commits at ffffffffa05ec91d [reiserfs]
 #5 [ffff8802244c3e08] process_one_work at ffffffff81073726
 #6 [ffff8802244c3e68] worker_thread at ffffffff81073eba
 #7 [ffff8802244c3ec8] kthread at ffffffff810782e0
 #8 [ffff8802244c3f48] kernel_thread_helper at ffffffff81450064
crash> rd ffff8802244c3cc8 10
ffff8802244c3cc8:  ffffffff814472b3 ffff880222f23250   .rD.....P2."....
ffff8802244c3cd8:  0000000000000000 0000000000000286   ................
ffff8802244c3ce8:  ffff8802244c3d30 ffff880220734d80   0=L$.....Ms ....
ffff8802244c3cf8:  ffff880222e8f628 0000000000000000   (.."............
ffff8802244c3d08:  0000000000000000 0000000000000002   ................
crash> struct rt_mutex ffff880222e8f628
struct rt_mutex {
  wait_lock = {
    raw_lock = {
      slock = 65537
    }
  },
  wait_list = {
    node_list = {
      next = 0xffff8802244c3d48,
      prev = 0xffff8802244c3d48
    }
  },
  owner = 0xffff880222f22c71,
  save_state = 0
}
crash> bt 0xffff880222f22c70
PID: 10635  TASK: ffff880222f22c70  CPU: 3   COMMAND: "mount"
 #0 [ffff8802216a9868] schedule at ffffffff8144584b
 #1 [ffff8802216a9910] schedule_timeout at ffffffff81446865
 #2 [ffff8802216a99a0] wait_for_common at ffffffff81445f74
 #3 [ffff8802216a9a30] flush_work at ffffffff810712d3
 #4 [ffff8802216a9ab0] schedule_on_each_cpu at ffffffff81074463
 #5 [ffff8802216a9ae0] invalidate_bdev at ffffffff81178aba
 #6 [ffff8802216a9af0] vfs_load_quota_inode at ffffffff811a3632
 #7 [ffff8802216a9b50] dquot_quota_on_mount at ffffffff811a375c
 #8 [ffff8802216a9b80] finish_unfinished at ffffffffa05dd8b0 [reiserfs]
 #9 [ffff8802216a9cc0] reiserfs_fill_super at ffffffffa05de825 [reiserfs]
    RIP: 00007f7b9303997a  RSP: 00007ffff443c7a8  RFLAGS: 00010202
    RAX: 00000000000000a5  RBX: ffffffff8144ef12  RCX: 00007f7b932e9ee0
    RDX: 00007f7b93d9a400  RSI: 00007f7b93d9a3e0  RDI: 00007f7b93d9a3c0
    RBP: 00007f7b93d9a2c0   R8: 00007f7b93d9a550   R9: 0000000000000001
    R10: ffffffffc0ed040e  R11: 0000000000000202  R12: 000000000000040e
    R13: 0000000000000000  R14: 00000000c0ed040e  R15: 00007ffff443ca20
    ORIG_RAX: 00000000000000a5  CS: 0033  SS: 002b

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Mike Galbraith <mgalbraith@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request Dec 7, 2016
commit f659b10 upstream.

As the documentation for kthread_stop() says, "if threadfn() may call
do_exit() itself, the caller must ensure task_struct can't go away".
dm-crypt does not ensure this and therefore crashes when crypt_dtr()
calls kthread_stop().  The crash is trivially reproducible by adding a
delay before the call to kthread_stop() and just opening and closing a
dm-crypt device.

 general protection fault: 0000 [#1] PREEMPT SMP
 CPU: 0 PID: 533 Comm: cryptsetup Not tainted 4.8.0-rc7+ #7
 task: ffff88003bd0df40 task.stack: ffff8800375b4000
 RIP: 0010: kthread_stop+0x52/0x300
 Call Trace:
  crypt_dtr+0x77/0x120
  dm_table_destroy+0x6f/0x120
  __dm_destroy+0x130/0x250
  dm_destroy+0x13/0x20
  dev_remove+0xe6/0x120
  ? dev_suspend+0x250/0x250
  ctl_ioctl+0x1fc/0x530
  ? __lock_acquire+0x24f/0x1b10
  dm_ctl_ioctl+0x13/0x20
  do_vfs_ioctl+0x91/0x6a0
  ? ____fput+0xe/0x10
  ? entry_SYSCALL_64_fastpath+0x5/0xbd
  ? trace_hardirqs_on_caller+0x151/0x1e0
  SyS_ioctl+0x41/0x70
  entry_SYSCALL_64_fastpath+0x1f/0xbd

This problem was introduced by bcbd94f ("dm crypt: fix a possible
hang due to race condition on exit").

Looking at the description of that patch (excerpted below), it seems
like the problem it addresses can be solved by just using
set_current_state instead of __set_current_state, since we obviously
need the memory barrier.

| dm crypt: fix a possible hang due to race condition on exit
|
| A kernel thread executes __set_current_state(TASK_INTERRUPTIBLE),
| __add_wait_queue, spin_unlock_irq and then tests kthread_should_stop().
| It is possible that the processor reorders memory accesses so that
| kthread_should_stop() is executed before __set_current_state().  If
| such reordering happens, there is a possible race on thread
| termination: [...]

So this patch just reverts the aforementioned patch and changes the
__set_current_state(TASK_INTERRUPTIBLE) to set_current_state(...).  This
fixes the crash and should also fix the potential hang.

Fixes: bcbd94f ("dm crypt: fix a possible hang due to race condition on exit")
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request Dec 7, 2016
commit b6bc1c7 upstream.

Function ib_create_qp() was failing to return an error when
rdma_rw_init_mrs() fails, causing a crash further down in ib_create_qp()
when trying to dereferece the qp pointer which was actually a negative
errno.

The crash:

crash> log|grep BUG
[  136.458121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
crash> bt
PID: 3736   TASK: ffff8808543215c0  CPU: 2   COMMAND: "kworker/u64:2"
 #0 [ffff88084d323340] machine_kexec at ffffffff8105fbb0
 #1 [ffff88084d3233b0] __crash_kexec at ffffffff81116758
 #2 [ffff88084d323480] crash_kexec at ffffffff8111682d
 #3 [ffff88084d3234b0] oops_end at ffffffff81032bd6
 #4 [ffff88084d3234e0] no_context at ffffffff8106e431
 #5 [ffff88084d323530] __bad_area_nosemaphore at ffffffff8106e610
 #6 [ffff88084d323590] bad_area_nosemaphore at ffffffff8106e6f4
 #7 [ffff88084d3235a0] __do_page_fault at ffffffff8106ebdc
 #8 [ffff88084d323620] do_page_fault at ffffffff8106f057
 #9 [ffff88084d323660] page_fault at ffffffff816e3148
    [exception RIP: ib_create_qp+427]
    RIP: ffffffffa02554fb  RSP: ffff88084d323718  RFLAGS: 00010246
    RAX: 0000000000000004  RBX: fffffffffffffff4  RCX: 000000018020001f
    RDX: ffff880830997fc0  RSI: 0000000000000001  RDI: ffff88085f407200
    RBP: ffff88084d323778   R8: 0000000000000001   R9: ffffea0020bae210
    R10: ffffea0020bae218  R11: 0000000000000001  R12: ffff88084d3237c8
    R13: 00000000fffffff4  R14: ffff880859fa5000  R15: ffff88082eb89800
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
#10 [ffff88084d323780] rdma_create_qp at ffffffffa0782681 [rdma_cm]
#11 [ffff88084d3237b0] nvmet_rdma_create_queue_ib at ffffffffa07c43f3 [nvmet_rdma]
#12 [ffff88084d323860] nvmet_rdma_alloc_queue at ffffffffa07c5ba9 [nvmet_rdma]
#13 [ffff88084d323900] nvmet_rdma_queue_connect at ffffffffa07c5c96 [nvmet_rdma]
#14 [ffff88084d323980] nvmet_rdma_cm_handler at ffffffffa07c6450 [nvmet_rdma]
#15 [ffff88084d3239b0] iw_conn_req_handler at ffffffffa0787480 [rdma_cm]
#16 [ffff88084d323a60] cm_conn_req_handler at ffffffffa0775f06 [iw_cm]
#17 [ffff88084d323ab0] process_event at ffffffffa0776019 [iw_cm]
#18 [ffff88084d323af0] cm_work_handler at ffffffffa0776170 [iw_cm]
#19 [ffff88084d323cb0] process_one_work at ffffffff810a1483
#20 [ffff88084d323d90] worker_thread at ffffffff810a211d
#21 [ffff88084d323ec0] kthread at ffffffff810a6c5c
#22 [ffff88084d323f50] ret_from_fork at ffffffff816e1ebf

Fixes: 632bc3f ("IB/core, RDMA RW API: Do not exceed QP SGE send limit")
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request Apr 28, 2017
commit a782b5f upstream.

Previously we checked for iATU unroll support by reading PCIE_ATU_VIEWPORT
even on platforms, e.g., Keystone, that do not have ATU ports.  This can
cause bad behavior such as asynchronous external aborts:

  OF: PCI:   MEM 0x60000000..0x6fffffff -> 0x60000000
  Unhandled fault: asynchronous external abort (0x1211) at 0x00000000
  pgd = c0003000
  [00000000] *pgd=80000800004003, *pmd=00000000
  Internal error: : 1211 [#1] PREEMPT SMP ARM
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-00009-g6ff59d2-dirty #7
  Hardware name: Keystone
  task: eb878000 task.stack: eb866000
  PC is at dw_pcie_setup_rc+0x24/0x380
  LR is at ks_pcie_host_init+0x10/0x170

Move the dw_pcie_iatu_unroll_enabled() check so we only call it on
platforms that do not use the ATU.  These platforms supply their own
->rd_other_conf() and ->wr_other_conf() methods.

[bhelgaas: changelog]
Fixes: a0601a4 ("PCI: designware: Add iATU Unroll feature")
Fixes: 416379f ("PCI: designware: Check for iATU unroll support after initializing host")
Tested-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-By: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request May 11, 2017
[ Upstream commit c70b17b ]

Reducing real_num_tx_queues needs to be in sync with skb queue_mapping
otherwise skbs with queue_mapping greater than real_num_tx_queues
can be sent to the underlying driver and can result in kernel panic.

One such event is running netconsole and enabling VF on the same
device. Or running netconsole and changing number of tx queues via
ethtool on same device.

e.g.
Unable to handle kernel NULL pointer dereference
tsk->{mm,active_mm}->context = 0000000000001525
tsk->{mm,active_mm}->pgd = fff800130ff9a000
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
kworker/48:1(475): Oops [#1]
CPU: 48 PID: 475 Comm: kworker/48:1 Tainted: G           OE
4.11.0-rc3-davem-net+ #7
Workqueue: events queue_process
task: fff80013113299c0 task.stack: fff800131132c000
TSTATE: 0000004480e01600 TPC: 00000000103f9e3c TNPC: 00000000103f9e40 Y:
00000000    Tainted: G           OE
TPC: <ixgbe_xmit_frame_ring+0x7c/0x6c0 [ixgbe]>
g0: 0000000000000000 g1: 0000000000003fff g2: 0000000000000000 g3:
0000000000000001
g4: fff80013113299c0 g5: fff8001fa6808000 g6: fff800131132c000 g7:
00000000000000c0
o0: fff8001fa760c460 o1: fff8001311329a50 o2: fff8001fa7607504 o3:
0000000000000003
o4: fff8001f96e63a40 o5: fff8001311d77ec0 sp: fff800131132f0e1 ret_pc:
000000000049ed94
RPC: <set_next_entity+0x34/0xb80>
l0: 0000000000000000 l1: 0000000000000800 l2: 0000000000000000 l3:
0000000000000000
l4: 000b2aa30e34b10d l5: 0000000000000000 l6: 0000000000000000 l7:
fff8001fa7605028
i0: fff80013111a8a00 i1: fff80013155a0780 i2: 0000000000000000 i3:
0000000000000000
i4: 0000000000000000 i5: 0000000000100000 i6: fff800131132f1a1 i7:
00000000103fa4b0
I7: <ixgbe_xmit_frame+0x30/0xa0 [ixgbe]>
Call Trace:
 [00000000103fa4b0] ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
 [0000000000998c74] netpoll_start_xmit+0xf4/0x200
 [0000000000998e10] queue_process+0x90/0x160
 [0000000000485fa8] process_one_work+0x188/0x480
 [0000000000486410] worker_thread+0x170/0x4c0
 [000000000048c6b8] kthread+0xd8/0x120
 [0000000000406064] ret_from_fork+0x1c/0x2c
 [0000000000000000]           (null)
Disabling lock debugging due to kernel taint
Caller[00000000103fa4b0]: ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
Caller[0000000000998c74]: netpoll_start_xmit+0xf4/0x200
Caller[0000000000998e10]: queue_process+0x90/0x160
Caller[0000000000485fa8]: process_one_work+0x188/0x480
Caller[0000000000486410]: worker_thread+0x170/0x4c0
Caller[000000000048c6b8]: kthread+0xd8/0x120
Caller[0000000000406064]: ret_from_fork+0x1c/0x2c
Caller[0000000000000000]:           (null)

Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bergwolf pushed a commit that referenced this pull request May 11, 2017
Dmitry reported a lockdep splat [1] (false positive) that we can fix
by releasing the spinlock before calling icmp_send() from ip_expire()

This is a false positive because sending an ICMP message can not
possibly re-enter the IP frag engine.

[1]
[ INFO: possible circular locking dependency detected ]
4.10.0+ #29 Not tainted
-------------------------------------------------------
modprobe/12392 is trying to acquire lock:
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] spin_lock
include/linux/spinlock.h:299 [inline]
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>] __netif_tx_lock
include/linux/netdevice.h:3486 [inline]
 (_xmit_ETHER#2){+.-...}, at: [<ffffffff837a8182>]
sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180

but task is already holding lock:
 (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock
include/linux/spinlock.h:299 [inline]
 (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>]
ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&(&q->lock)->rlock){+.-...}:
       validate_chain kernel/locking/lockdep.c:2267 [inline]
       __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
       lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
       spin_lock include/linux/spinlock.h:299 [inline]
       ip_defrag+0x3a2/0x4130 net/ipv4/ip_fragment.c:669
       ip_check_defrag+0x4e3/0x8b0 net/ipv4/ip_fragment.c:713
       packet_rcv_fanout+0x282/0x800 net/packet/af_packet.c:1459
       deliver_skb net/core/dev.c:1834 [inline]
       dev_queue_xmit_nit+0x294/0xa90 net/core/dev.c:1890
       xmit_one net/core/dev.c:2903 [inline]
       dev_hard_start_xmit+0x16b/0xab0 net/core/dev.c:2923
       sch_direct_xmit+0x31f/0x6d0 net/sched/sch_generic.c:182
       __dev_xmit_skb net/core/dev.c:3092 [inline]
       __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
       dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
       neigh_resolve_output+0x6b9/0xb10 net/core/neighbour.c:1308
       neigh_output include/net/neighbour.h:478 [inline]
       ip_finish_output2+0x8b8/0x15a0 net/ipv4/ip_output.c:228
       ip_do_fragment+0x1d93/0x2720 net/ipv4/ip_output.c:672
       ip_fragment.constprop.54+0x145/0x200 net/ipv4/ip_output.c:545
       ip_finish_output+0x82d/0xe10 net/ipv4/ip_output.c:314
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
       dst_output include/net/dst.h:486 [inline]
       ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
       ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
       ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
       raw_sendmsg+0x26de/0x3a00 net/ipv4/raw.c:655
       inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:761
       sock_sendmsg_nosec net/socket.c:633 [inline]
       sock_sendmsg+0xca/0x110 net/socket.c:643
       ___sys_sendmsg+0x4a3/0x9f0 net/socket.c:1985
       __sys_sendmmsg+0x25c/0x750 net/socket.c:2075
       SYSC_sendmmsg net/socket.c:2106 [inline]
       SyS_sendmmsg+0x35/0x60 net/socket.c:2101
       do_syscall_64+0x2e8/0x930 arch/x86/entry/common.c:281
       return_from_SYSCALL_64+0x0/0x7a

-> #0 (_xmit_ETHER#2){+.-...}:
       check_prev_add kernel/locking/lockdep.c:1830 [inline]
       check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940
       validate_chain kernel/locking/lockdep.c:2267 [inline]
       __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
       lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
       spin_lock include/linux/spinlock.h:299 [inline]
       __netif_tx_lock include/linux/netdevice.h:3486 [inline]
       sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180
       __dev_xmit_skb net/core/dev.c:3092 [inline]
       __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
       dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
       neigh_hh_output include/net/neighbour.h:468 [inline]
       neigh_output include/net/neighbour.h:476 [inline]
       ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228
       ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
       dst_output include/net/dst.h:486 [inline]
       ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
       ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
       ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
       icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394
       icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754
       ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239
       call_timer_fn+0x241/0x820 kernel/time/timer.c:1268
       expire_timers kernel/time/timer.c:1307 [inline]
       __run_timers+0x960/0xcf0 kernel/time/timer.c:1601
       run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614
       __do_softirq+0x31f/0xbe7 kernel/softirq.c:284
       invoke_softirq kernel/softirq.c:364 [inline]
       irq_exit+0x1cc/0x200 kernel/softirq.c:405
       exiting_irq arch/x86/include/asm/apic.h:657 [inline]
       smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962
       apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707
       __read_once_size include/linux/compiler.h:254 [inline]
       atomic_read arch/x86/include/asm/atomic.h:26 [inline]
       rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline]
       __rcu_is_watching kernel/rcu/tree.c:1133 [inline]
       rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147
       rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293
       radix_tree_deref_slot include/linux/radix-tree.h:238 [inline]
       filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335
       do_fault_around mm/memory.c:3231 [inline]
       do_read_fault mm/memory.c:3265 [inline]
       do_fault+0xbd5/0x2080 mm/memory.c:3370
       handle_pte_fault mm/memory.c:3600 [inline]
       __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714
       handle_mm_fault+0x1e2/0x480 mm/memory.c:3751
       __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397
       do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460
       page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&q->lock)->rlock);
                               lock(_xmit_ETHER#2);
                               lock(&(&q->lock)->rlock);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

10 locks held by modprobe/12392:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff81329758>]
__do_page_fault+0x2b8/0xb60 arch/x86/mm/fault.c:1336
 #1:  (rcu_read_lock){......}, at: [<ffffffff8188cab6>]
filemap_map_pages+0x1e6/0x1570 mm/filemap.c:2324
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
spin_lock include/linux/spinlock.h:299 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
pte_alloc_one_map mm/memory.c:2944 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff81984a78>]
alloc_set_pte+0x13b8/0x1b90 mm/memory.c:3072
 #3:  (((&q->timer))){+.-...}, at: [<ffffffff81627e72>]
lockdep_copy_map include/linux/lockdep.h:175 [inline]
 #3:  (((&q->timer))){+.-...}, at: [<ffffffff81627e72>]
call_timer_fn+0x1c2/0x820 kernel/time/timer.c:1258
 #4:  (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>] spin_lock
include/linux/spinlock.h:299 [inline]
 #4:  (&(&q->lock)->rlock){+.-...}, at: [<ffffffff8389a4d1>]
ip_expire+0x51/0x6c0 net/ipv4/ip_fragment.c:201
 #5:  (rcu_read_lock){......}, at: [<ffffffff8389a633>]
ip_expire+0x1b3/0x6c0 net/ipv4/ip_fragment.c:216
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] spin_trylock
include/linux/spinlock.h:309 [inline]
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>] icmp_xmit_lock
net/ipv4/icmp.c:219 [inline]
 #6:  (slock-AF_INET){+.-...}, at: [<ffffffff839b3313>]
icmp_send+0x803/0x1c80 net/ipv4/icmp.c:681
 #7:  (rcu_read_lock_bh){......}, at: [<ffffffff838ab9a1>]
ip_finish_output2+0x2c1/0x15a0 net/ipv4/ip_output.c:198
 #8:  (rcu_read_lock_bh){......}, at: [<ffffffff836d1dee>]
__dev_queue_xmit+0x23e/0x1e60 net/core/dev.c:3324
 #9:  (dev->qdisc_running_key ?: &qdisc_running_key){+.....}, at:
[<ffffffff836d3a27>] dev_queue_xmit+0x17/0x20 net/core/dev.c:3423

stack backtrace:
CPU: 0 PID: 12392 Comm: modprobe Not tainted 4.10.0+ #29
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x2ee/0x3ef lib/dump_stack.c:52
 print_circular_bug+0x307/0x3b0 kernel/locking/lockdep.c:1204
 check_prev_add kernel/locking/lockdep.c:1830 [inline]
 check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1940
 validate_chain kernel/locking/lockdep.c:2267 [inline]
 __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3340
 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:299 [inline]
 __netif_tx_lock include/linux/netdevice.h:3486 [inline]
 sch_direct_xmit+0x282/0x6d0 net/sched/sch_generic.c:180
 __dev_xmit_skb net/core/dev.c:3092 [inline]
 __dev_queue_xmit+0x13e5/0x1e60 net/core/dev.c:3358
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3423
 neigh_hh_output include/net/neighbour.h:468 [inline]
 neigh_output include/net/neighbour.h:476 [inline]
 ip_finish_output2+0xf6c/0x15a0 net/ipv4/ip_output.c:228
 ip_finish_output+0xa29/0xe10 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:246 [inline]
 ip_output+0x1f0/0x7a0 net/ipv4/ip_output.c:404
 dst_output include/net/dst.h:486 [inline]
 ip_local_out+0x95/0x170 net/ipv4/ip_output.c:124
 ip_send_skb+0x3c/0xc0 net/ipv4/ip_output.c:1492
 ip_push_pending_frames+0x64/0x80 net/ipv4/ip_output.c:1512
 icmp_push_reply+0x372/0x4d0 net/ipv4/icmp.c:394
 icmp_send+0x156c/0x1c80 net/ipv4/icmp.c:754
 ip_expire+0x40e/0x6c0 net/ipv4/ip_fragment.c:239
 call_timer_fn+0x241/0x820 kernel/time/timer.c:1268
 expire_timers kernel/time/timer.c:1307 [inline]
 __run_timers+0x960/0xcf0 kernel/time/timer.c:1601
 run_timer_softirq+0x21/0x80 kernel/time/timer.c:1614
 __do_softirq+0x31f/0xbe7 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:657 [inline]
 smp_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:962
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:707
RIP: 0010:__read_once_size include/linux/compiler.h:254 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline]
RIP: 0010:__rcu_is_watching kernel/rcu/tree.c:1133 [inline]
RIP: 0010:rcu_is_watching+0x83/0x110 kernel/rcu/tree.c:1147
RSP: 0000:ffff8801c391f120 EFLAGS: 00000a03 ORIG_RAX: ffffffffffffff10
RAX: dffffc0000000000 RBX: ffff8801c391f148 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000055edd4374000 RDI: ffff8801dbe1ae0c
RBP: ffff8801c391f1a0 R08: 0000000000000002 R09: 0000000000000000
R10: dffffc0000000000 R11: 0000000000000002 R12: 1ffff10038723e25
R13: ffff8801dbe1ae00 R14: ffff8801c391f680 R15: dffffc0000000000
 </IRQ>
 rcu_read_lock_held+0x87/0xc0 kernel/rcu/update.c:293
 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline]
 filemap_map_pages+0x6d4/0x1570 mm/filemap.c:2335
 do_fault_around mm/memory.c:3231 [inline]
 do_read_fault mm/memory.c:3265 [inline]
 do_fault+0xbd5/0x2080 mm/memory.c:3370
 handle_pte_fault mm/memory.c:3600 [inline]
 __handle_mm_fault+0x1062/0x2cb0 mm/memory.c:3714
 handle_mm_fault+0x1e2/0x480 mm/memory.c:3751
 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1397
 do_page_fault+0x54/0x70 arch/x86/mm/fault.c:1460
 page_fault+0x28/0x30 arch/x86/entry/entry_64.S:1011
RIP: 0033:0x7f83172f2786
RSP: 002b:00007fffe859ae80 EFLAGS: 00010293
RAX: 000055edd4373040 RBX: 00007f83175111c8 RCX: 000055edd4373238
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f8317510970
RBP: 00007fffe859afd0 R08: 0000000000000009 R09: 0000000000000000
R10: 0000000000000064 R11: 0000000000000000 R12: 000055edd4373040
R13: 0000000000000000 R14: 00007fffe859afe8 R15: 0000000000000000

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bergwolf pushed a commit that referenced this pull request May 11, 2017
mipsxx_pmu_handle_shared_irq() calls irq_work_run() while holding the
pmuint_rwlock for read.  irq_work_run() can, via perf_pending_event(),
call try_to_wake_up() which can try to take rq->lock.

However, perf can also call perf_pmu_enable() (and thus take the
pmuint_rwlock for write) while holding the rq->lock, from
finish_task_switch() via perf_event_context_sched_in().

This leads to an ABBA deadlock:

 PID: 3855   TASK: 8f7ce288  CPU: 2   COMMAND: "process"
  #0 [89c39ac8] __delay at 803b5be4
  #1 [89c39ac8] do_raw_spin_lock at 8008fdcc
  #2 [89c39af8] try_to_wake_up at 8006e47c
  #3 [89c39b38] pollwake at 8018eab0
  #4 [89c39b68] __wake_up_common at 800879f4
  #5 [89c39b98] __wake_up at 800880e4
  #6 [89c39bc8] perf_event_wakeup at 8012109c
  #7 [89c39be8] perf_pending_event at 80121184
  #8 [89c39c08] irq_work_run_list at 801151f0
  #9 [89c39c38] irq_work_run at 80115274
 #10 [89c39c50] mipsxx_pmu_handle_shared_irq at 8002cc7c

 PID: 1481   TASK: 8eaac6a8  CPU: 3   COMMAND: "process"
  #0 [8de7f900] do_raw_write_lock at 800900e0
  #1 [8de7f918] perf_event_context_sched_in at 80122310
  #2 [8de7f938] __perf_event_task_sched_in at 80122608
  #3 [8de7f958] finish_task_switch at 8006b8a4
  #4 [8de7f998] __schedule at 805e4dc4
  #5 [8de7f9f8] schedule at 805e5558
  #6 [8de7fa10] schedule_hrtimeout_range_clock at 805e9984
  #7 [8de7fa70] poll_schedule_timeout at 8018e8f8
  #8 [8de7fa88] do_select at 8018f338
  #9 [8de7fd88] core_sys_select at 8018f5cc
 #10 [8de7fee0] sys_select at 8018f854
 #11 [8de7ff28] syscall_common at 80028fc8

The lock seems to be there to protect the hardware counters so there is
no need to hold it across irq_work_run().

Signed-off-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
bergwolf pushed a commit that referenced this pull request May 11, 2017
Reducing real_num_tx_queues needs to be in sync with skb queue_mapping
otherwise skbs with queue_mapping greater than real_num_tx_queues
can be sent to the underlying driver and can result in kernel panic.

One such event is running netconsole and enabling VF on the same
device. Or running netconsole and changing number of tx queues via
ethtool on same device.

e.g.
Unable to handle kernel NULL pointer dereference
tsk->{mm,active_mm}->context = 0000000000001525
tsk->{mm,active_mm}->pgd = fff800130ff9a000
              \|/ ____ \|/
              "@'/ .. \`@"
              /_| \__/ |_\
                 \__U_/
kworker/48:1(475): Oops [#1]
CPU: 48 PID: 475 Comm: kworker/48:1 Tainted: G           OE
4.11.0-rc3-davem-net+ #7
Workqueue: events queue_process
task: fff80013113299c0 task.stack: fff800131132c000
TSTATE: 0000004480e01600 TPC: 00000000103f9e3c TNPC: 00000000103f9e40 Y:
00000000    Tainted: G           OE
TPC: <ixgbe_xmit_frame_ring+0x7c/0x6c0 [ixgbe]>
g0: 0000000000000000 g1: 0000000000003fff g2: 0000000000000000 g3:
0000000000000001
g4: fff80013113299c0 g5: fff8001fa6808000 g6: fff800131132c000 g7:
00000000000000c0
o0: fff8001fa760c460 o1: fff8001311329a50 o2: fff8001fa7607504 o3:
0000000000000003
o4: fff8001f96e63a40 o5: fff8001311d77ec0 sp: fff800131132f0e1 ret_pc:
000000000049ed94
RPC: <set_next_entity+0x34/0xb80>
l0: 0000000000000000 l1: 0000000000000800 l2: 0000000000000000 l3:
0000000000000000
l4: 000b2aa30e34b10d l5: 0000000000000000 l6: 0000000000000000 l7:
fff8001fa7605028
i0: fff80013111a8a00 i1: fff80013155a0780 i2: 0000000000000000 i3:
0000000000000000
i4: 0000000000000000 i5: 0000000000100000 i6: fff800131132f1a1 i7:
00000000103fa4b0
I7: <ixgbe_xmit_frame+0x30/0xa0 [ixgbe]>
Call Trace:
 [00000000103fa4b0] ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
 [0000000000998c74] netpoll_start_xmit+0xf4/0x200
 [0000000000998e10] queue_process+0x90/0x160
 [0000000000485fa8] process_one_work+0x188/0x480
 [0000000000486410] worker_thread+0x170/0x4c0
 [000000000048c6b8] kthread+0xd8/0x120
 [0000000000406064] ret_from_fork+0x1c/0x2c
 [0000000000000000]           (null)
Disabling lock debugging due to kernel taint
Caller[00000000103fa4b0]: ixgbe_xmit_frame+0x30/0xa0 [ixgbe]
Caller[0000000000998c74]: netpoll_start_xmit+0xf4/0x200
Caller[0000000000998e10]: queue_process+0x90/0x160
Caller[0000000000485fa8]: process_one_work+0x188/0x480
Caller[0000000000486410]: worker_thread+0x170/0x4c0
Caller[000000000048c6b8]: kthread+0xd8/0x120
Caller[0000000000406064]: ret_from_fork+0x1c/0x2c
Caller[0000000000000000]:           (null)

Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
pull bot pushed a commit that referenced this pull request Jun 5, 2020
Implement rtas_call_reentrant() for reentrant rtas-calls:
"ibm,int-on", "ibm,int-off",ibm,get-xive" and  "ibm,set-xive".

On LoPAPR Version 1.1 (March 24, 2016), from 7.3.10.1 to 7.3.10.4,
items 2 and 3 say:

2 - For the PowerPC External Interrupt option: The * call must be
reentrant to the number of processors on the platform.
3 - For the PowerPC External Interrupt option: The * argument call
buffer for each simultaneous call must be physically unique.

So, these rtas-calls can be called in a lockless way, if using
a different buffer for each cpu doing such rtas call.

For this, it was suggested to add the buffer (struct rtas_args)
in the PACA struct, so each cpu can have it's own buffer.
The PACA struct received a pointer to rtas buffer, which is
allocated in the memory range available to rtas 32-bit.

Reentrant rtas calls are useful to avoid deadlocks in crashing,
where rtas-calls are needed, but some other thread crashed holding
the rtas.lock.

This is a backtrace of a deadlock from a kdump testing environment:

  #0 arch_spin_lock
  #1  lock_rtas ()
  #2  rtas_call (token=8204, nargs=1, nret=1, outputs=0x0)
  #3  ics_rtas_mask_real_irq (hw_irq=4100)
  #4  machine_kexec_mask_interrupts
  #5  default_machine_crash_shutdown
  #6  machine_crash_shutdown
  #7  __crash_kexec
  #8  crash_kexec
  #9  oops_end

Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
[mpe: Move under #ifdef PSERIES to avoid build breakage]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200518234245.200672-3-leobras.c@gmail.com
pull bot pushed a commit that referenced this pull request Jun 12, 2020
The first version of Clang that supports -tsan-distinguish-volatile will
be able to support KCSAN. The first Clang release to do so, will be
Clang 11. This is due to satisfying all the following requirements:

1. Never emit calls to __tsan_func_{entry,exit}.

2. __no_kcsan functions should not call anything, not even
   kcsan_{enable,disable}_current(), when using __{READ,WRITE}_ONCE => Requires
   leaving them plain!

3. Support atomic_{read,set}*() with KCSAN, which rely on
   arch_atomic_{read,set}*() using __{READ,WRITE}_ONCE() => Because of
   #2, rely on Clang 11's -tsan-distinguish-volatile support. We will
   double-instrument atomic_{read,set}*(), but that's reasonable given
   it's still lower cost than the data_race() variant due to avoiding 2
   extra calls (kcsan_{en,dis}able_current() calls).

4. __always_inline functions inlined into __no_kcsan functions are never
   instrumented.

5. __always_inline functions inlined into instrumented functions are
   instrumented.

6. __no_kcsan_or_inline functions may be inlined into __no_kcsan functions =>
   Implies leaving 'noinline' off of __no_kcsan_or_inline.

7. Because of #6, __no_kcsan and __no_kcsan_or_inline functions should never be
   spuriously inlined into instrumented functions, causing the accesses of the
   __no_kcsan function to be instrumented.

Older versions of Clang do not satisfy #3. The latest GCC currently
doesn't support at least #1, #3, and #7.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-7-elver@google.com
pull bot pushed a commit that referenced this pull request Jan 5, 2025
The folio refcount may be increased unexpectly through try_get_folio() by
caller such as split_huge_pages.  In huge_pmd_unshare(), we use refcount
to check whether a pmd page table is shared.  The check is incorrect if
the refcount is increased by the above caller, and this can cause the page
table leaked:

 BUG: Bad page state in process sh  pfn:109324
 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x66 pfn:0x109324
 flags: 0x17ffff800000000(node=0|zone=2|lastcpupid=0xfffff)
 page_type: f2(table)
 raw: 017ffff800000000 0000000000000000 0000000000000000 0000000000000000
 raw: 0000000000000066 0000000000000000 00000000f2000000 0000000000000000
 page dumped because: nonzero mapcount
 ...
 CPU: 31 UID: 0 PID: 7515 Comm: sh Kdump: loaded Tainted: G    B              6.13.0-rc2master+ #7
 Tainted: [B]=BAD_PAGE
 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
 Call trace:
  show_stack+0x20/0x38 (C)
  dump_stack_lvl+0x80/0xf8
  dump_stack+0x18/0x28
  bad_page+0x8c/0x130
  free_page_is_bad_report+0xa4/0xb0
  free_unref_page+0x3cc/0x620
  __folio_put+0xf4/0x158
  split_huge_pages_all+0x1e0/0x3e8
  split_huge_pages_write+0x25c/0x2d8
  full_proxy_write+0x64/0xd8
  vfs_write+0xcc/0x280
  ksys_write+0x70/0x110
  __arm64_sys_write+0x24/0x38
  invoke_syscall+0x50/0x120
  el0_svc_common.constprop.0+0xc8/0xf0
  do_el0_svc+0x24/0x38
  el0_svc+0x34/0x128
  el0t_64_sync_handler+0xc8/0xd0
  el0t_64_sync+0x190/0x198

The issue may be triggered by damon, offline_page, page_idle, etc, which
will increase the refcount of page table.

1. The page table itself will be discarded after reporting the
   "nonzero mapcount".

2. The HugeTLB page mapped by the page table miss freeing since we
   treat the page table as shared and a shared page table will not be
   unmapped.

Fix it by introducing independent PMD page table shared count.  As
described by comment, pt_index/pt_mm/pt_frag_refcount are used for s390
gmap, x86 pgds and powerpc, pt_share_count is used for x86/arm64/riscv
pmds, so we can reuse the field as pt_share_count.

Link: https://lkml.kernel.org/r/20241216071147.3984217-1-liushixin2@huawei.com
Fixes: 39dde65 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Ken Chen <kenneth.w.chen@intel.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pull bot pushed a commit that referenced this pull request Jan 23, 2025
Commit 82c1f13 ("selftests/bpf: Add more stats into veristat")
introduced new stats, added by default in the CSV output, that were not
added to parse_stat_value, used in parse_stats_csv which is used in
comparison mode. Thus it broke comparison mode altogether making it fail
with "Unrecognized stat #7" and EINVAL.

One quirk is that PROG_TYPE and ATTACH_TYPE have been transformed to
strings using libbpf_bpf_prog_type_str and libbpf_bpf_attach_type_str
respectively. Since we might not want to compare those string values, we
just skip the parsing in this patch. We might want to translate it back
to the enum value or compare the string value directly.

Fixes: 82c1f13 ("selftests/bpf: Add more stats into veristat")
Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
Tested-by: Mykyta Yatsenko<yatsenko@meta.com>
Link: https://lore.kernel.org/r/20241220152218.28405-1-mahe.tardy@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
pull bot pushed a commit that referenced this pull request Jan 24, 2025
When kernel is built without debuginfo, running 'perf record' with
--off-cpu results in segfault as below:

   ./perf record --off-cpu -e dummy sleep 1
   libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
   libbpf: failed to find '.BTF' ELF section in /lib/modules/6.13.0-rc3+/build/vmlinux
   libbpf: failed to find valid kernel BTF
   Segmentation fault (core dumped)

The backtrace pointed to:

   #0  0x00000000100fb17c in btf.type_cnt ()
   #1  0x00000000100fc1a8 in btf_find_by_name_kind ()
   #2  0x00000000100fc38c in btf.find_by_name_kind ()
   #3  0x00000000102ee3ac in off_cpu_prepare ()
   #4  0x000000001002f78c in cmd_record ()
   #5  0x00000000100aee78 in run_builtin ()
   #6  0x00000000100af3e4 in handle_internal_command ()
   #7  0x000000001001004c in main ()

Code sequence is:

   static void check_sched_switch_args(void)
   {
        struct btf *btf = btf__load_vmlinux_btf();
        const struct btf_type *t1, *t2, *t3;
        u32 type_id;

        type_id = btf__find_by_name_kind(btf, "btf_trace_sched_switch",
                                         BTF_KIND_TYPEDEF);

btf__load_vmlinux_btf() fails when CONFIG_DEBUG_INFO_BTF is not enabled.

Here bpf__find_by_name_kind() calls btf__type_cnt() with NULL btf value
and results in segfault.

To fix this, add a check to see if btf is not NULL before invoking
bpf__find_by_name_kind().

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://lore.kernel.org/r/20241223135813.8175-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
pull bot pushed a commit that referenced this pull request Jan 31, 2025
libtraceevent parses and returns an array of argument fields, sometimes
larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr",
idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6
elements max, creating an out-of-bounds access. This runtime error is
found by UBsan. The error message:

  $ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1
  builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]'
    #0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966
    #1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110
    #2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436
    #3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897
    #4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335
    #5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502
    #6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351
    #7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404
    #8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448
    #9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556
    #10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
    #11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360
    #12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6)

     0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1)                                      = 1

Fixes: 5e58fcf ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint")
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Jan 31, 2025
Fix the suspend/resume path by ensuring the rtnl lock is held where
required. Calls to ravb_open, ravb_close and wol operations must be
performed under the rtnl lock to prevent conflicts with ongoing ndo
operations.

Without this fix, the following warning is triggered:
[   39.032969] =============================
[   39.032983] WARNING: suspicious RCU usage
[   39.033019] -----------------------------
[   39.033033] drivers/net/phy/phy_device.c:2004 suspicious
rcu_dereference_protected() usage!
...
[   39.033597] stack backtrace:
[   39.033613] CPU: 0 UID: 0 PID: 174 Comm: python3 Not tainted
6.13.0-rc7-next-20250116-arm64-renesas-00002-g35245dfdc62c #7
[   39.033623] Hardware name: Renesas SMARC EVK version 2 based on
r9a08g045s33 (DT)
[   39.033628] Call trace:
[   39.033633]  show_stack+0x14/0x1c (C)
[   39.033652]  dump_stack_lvl+0xb4/0xc4
[   39.033664]  dump_stack+0x14/0x1c
[   39.033671]  lockdep_rcu_suspicious+0x16c/0x22c
[   39.033682]  phy_detach+0x160/0x190
[   39.033694]  phy_disconnect+0x40/0x54
[   39.033703]  ravb_close+0x6c/0x1cc
[   39.033714]  ravb_suspend+0x48/0x120
[   39.033721]  dpm_run_callback+0x4c/0x14c
[   39.033731]  device_suspend+0x11c/0x4dc
[   39.033740]  dpm_suspend+0xdc/0x214
[   39.033748]  dpm_suspend_start+0x48/0x60
[   39.033758]  suspend_devices_and_enter+0x124/0x574
[   39.033769]  pm_suspend+0x1ac/0x274
[   39.033778]  state_store+0x88/0x124
[   39.033788]  kobj_attr_store+0x14/0x24
[   39.033798]  sysfs_kf_write+0x48/0x6c
[   39.033808]  kernfs_fop_write_iter+0x118/0x1a8
[   39.033817]  vfs_write+0x27c/0x378
[   39.033825]  ksys_write+0x64/0xf4
[   39.033833]  __arm64_sys_write+0x18/0x20
[   39.033841]  invoke_syscall+0x44/0x104
[   39.033852]  el0_svc_common.constprop.0+0xb4/0xd4
[   39.033862]  do_el0_svc+0x18/0x20
[   39.033870]  el0_svc+0x3c/0xf0
[   39.033880]  el0t_64_sync_handler+0xc0/0xc4
[   39.033888]  el0t_64_sync+0x154/0x158
[   39.041274] ravb 11c30000.ethernet eth0: Link is Down

Reported-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Closes: https://lore.kernel.org/netdev/4c6419d8-c06b-495c-b987-d66c2e1ff848@tuxon.dev/
Fixes: 0184165 ("ravb: add sleep PM suspend/resume support")
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
pull bot pushed a commit that referenced this pull request Feb 1, 2025
This fixes the following hard lockup in isolate_lru_folios() during memory
reclaim.  If the LRU mostly contains ineligible folios this may trigger
watchdog.

watchdog: Watchdog detected hard LOCKUP on cpu 173
RIP: 0010:native_queued_spin_lock_slowpath+0x255/0x2a0
Call Trace:
	_raw_spin_lock_irqsave+0x31/0x40
	folio_lruvec_lock_irqsave+0x5f/0x90
	folio_batch_move_lru+0x91/0x150
	lru_add_drain_per_cpu+0x1c/0x40
	process_one_work+0x17d/0x350
	worker_thread+0x27b/0x3a0
	kthread+0xe8/0x120
	ret_from_fork+0x34/0x50
	ret_from_fork_asm+0x1b/0x30

lruvec->lru_lock owner:

PID: 2865     TASK: ffff888139214d40  CPU: 40   COMMAND: "kswapd0"
 #0 [fffffe0000945e60] crash_nmi_callback at ffffffffa567a555
 #1 [fffffe0000945e68] nmi_handle at ffffffffa563b171
 #2 [fffffe0000945eb0] default_do_nmi at ffffffffa6575920
 #3 [fffffe0000945ed0] exc_nmi at ffffffffa6575af4
 #4 [fffffe0000945ef0] end_repeat_nmi at ffffffffa6601dde
    [exception RIP: isolate_lru_folios+403]
    RIP: ffffffffa597df53  RSP: ffffc90006fb7c28  RFLAGS: 00000002
    RAX: 0000000000000001  RBX: ffffc90006fb7c60  RCX: ffffea04a2196f88
    RDX: ffffc90006fb7c60  RSI: ffffc90006fb7c60  RDI: ffffea04a2197048
    RBP: ffff88812cbd3010   R8: ffffea04a2197008   R9: 0000000000000001
    R10: 0000000000000000  R11: 0000000000000001  R12: ffffea04a2197008
    R13: ffffea04a2197048  R14: ffffc90006fb7de8  R15: 0000000003e3e937
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    <NMI exception stack>
 #5 [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53
 #6 [ffffc90006fb7cf8] shrink_active_list at ffffffffa597f788
 #7 [ffffc90006fb7da8] balance_pgdat at ffffffffa5986db0
 #8 [ffffc90006fb7ec0] kswapd at ffffffffa5987354
 #9 [ffffc90006fb7ef8] kthread at ffffffffa5748238
crash>

Scenario:
User processe are requesting a large amount of memory and keep page active.
Then a module continuously requests memory from ZONE_DMA32 area.
Memory reclaim will be triggered due to ZONE_DMA32 watermark alarm reached.
However pages in the LRU(active_anon) list are mostly from
the ZONE_NORMAL area.

Reproduce:
Terminal 1: Construct to continuously increase pages active(anon).
mkdir /tmp/memory
mount -t tmpfs -o size=1024000M tmpfs /tmp/memory
dd if=/dev/zero of=/tmp/memory/block bs=4M
tail /tmp/memory/block

Terminal 2:
vmstat -a 1
active will increase.
procs ---memory--- ---swap-- ---io---- -system-- ---cpu--- ...
 r  b   swpd   free  inact active   si   so    bi    bo
 1  0   0 1445623076 45898836 83646008    0    0     0
 1  0   0 1445623076 43450228 86094616    0    0     0
 1  0   0 1445623076 41003480 88541364    0    0     0
 1  0   0 1445623076 38557088 90987756    0    0     0
 1  0   0 1445623076 36109688 93435156    0    0     0
 1  0   0 1445619552 33663256 95881632    0    0     0
 1  0   0 1445619804 31217140 98327792    0    0     0
 1  0   0 1445619804 28769988 100774944    0    0     0
 1  0   0 1445619804 26322348 103222584    0    0     0
 1  0   0 1445619804 23875592 105669340    0    0     0

cat /proc/meminfo | head
Active(anon) increase.
MemTotal:       1579941036 kB
MemFree:        1445618500 kB
MemAvailable:   1453013224 kB
Buffers:            6516 kB
Cached:         128653956 kB
SwapCached:            0 kB
Active:         118110812 kB
Inactive:       11436620 kB
Active(anon):   115345744 kB
Inactive(anon):   945292 kB

When the Active(anon) is 115345744 kB, insmod module triggers
the ZONE_DMA32 watermark.

perf record -e vmscan:mm_vmscan_lru_isolate -aR
perf script
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=2
nr_skipped=2 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=0
nr_skipped=0 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=28835844
nr_skipped=28835844 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=1 nr_requested=32 nr_scanned=28835844
nr_skipped=28835844 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=29
nr_skipped=29 nr_taken=0 lru=active_anon
isolate_mode=0 classzone=1 order=0 nr_requested=32 nr_scanned=0
nr_skipped=0 nr_taken=0 lru=active_anon

See nr_scanned=28835844.
28835844 * 4k = 115343376KB approximately equal to 115345744 kB.

If increase Active(anon) to 1000G then insmod module triggers
the ZONE_DMA32 watermark. hard lockup will occur.

In my device nr_scanned = 0000000003e3e937 when hard lockup.
Convert to memory size 0x0000000003e3e937 * 4KB = 261072092 KB.

   [ffffc90006fb7c28] isolate_lru_folios at ffffffffa597df53
    ffffc90006fb7c30: 0000000000000020 0000000000000000
    ffffc90006fb7c40: ffffc90006fb7d40 ffff88812cbd3000
    ffffc90006fb7c50: ffffc90006fb7d30 0000000106fb7de8
    ffffc90006fb7c60: ffffea04a2197008 ffffea0006ed4a48
    ffffc90006fb7c70: 0000000000000000 0000000000000000
    ffffc90006fb7c80: 0000000000000000 0000000000000000
    ffffc90006fb7c90: 0000000000000000 0000000000000000
    ffffc90006fb7ca0: 0000000000000000 0000000003e3e937
    ffffc90006fb7cb0: 0000000000000000 0000000000000000
    ffffc90006fb7cc0: 8d7c0b56b7874b00 ffff88812cbd3000

About the Fixes:
Why did it take eight years to be discovered?

The problem requires the following conditions to occur:
1. The device memory should be large enough.
2. Pages in the LRU(active_anon) list are mostly from the ZONE_NORMAL area.
3. The memory in ZONE_DMA32 needs to reach the watermark.

If the memory is not large enough, or if the usage design of ZONE_DMA32
area memory is reasonable, this problem is difficult to detect.

notes:
The problem is most likely to occur in ZONE_DMA32 and ZONE_NORMAL,
but other suitable scenarios may also trigger the problem.

Link: https://lkml.kernel.org/r/20241119060842.274072-1-liuye@kylinos.cn
Fixes: b2e1875 ("mm, vmscan: begin reclaiming pages on a per-node basis")
Signed-off-by: liuye <liuye@kylinos.cn>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Yang Shi <yang@os.amperecomputing.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pull bot pushed a commit that referenced this pull request Feb 4, 2025
devm_platform_profile_register() expects a pointer to the private driver
data but instead an address of the pointer variable is passed due to a
typo. This leads to the crashes later:

BUG: unable to handle page fault for address: 00000000fe0d0044
PGD 0 P4D 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 6 UID: 0 PID: 1284 Comm: tuned Tainted: G        W          6.13.0+ #7
Tainted: [W]=WARN
Hardware name: LENOVO 21D0/LNVNB161216, BIOS J6CN45WW 03/17/2023
RIP: 0010:__mutex_lock.constprop.0+0x6bf/0x7f0
Call Trace:
 <TASK>
 dytc_profile_set+0x4a/0x140 [ideapad_laptop]
 _store_and_notify+0x13/0x40 [platform_profile]
 class_for_each_device+0x145/0x180
 platform_profile_store+0xc0/0x130 [platform_profile]
 kernfs_fop_write_iter+0x13e/0x1f0
 vfs_write+0x290/0x450
 ksys_write+0x6c/0xe0
 do_syscall_64+0x82/0x160
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Found by Linux Verification Center (linuxtesting.org).

Fixes: 249c576 ("ACPI: platform_profile: Let drivers set drvdata to the class device")
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Reviewed-by: Kurt Borja <kuurtb@gmail.com>
Link: https://lore.kernel.org/r/20250127210202.568691-1-pchelkin@ispras.ru
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
pull bot pushed a commit that referenced this pull request Feb 5, 2025
When COWing a relocation tree path, at relocation.c:replace_path(), we
can trigger a lockdep splat while we are in the btrfs_search_slot() call
against the relocation root. This happens in that callchain at
ctree.c:read_block_for_search() when we happen to find a child extent
buffer already loaded through the fs tree with a lockdep class set to
the fs tree. So when we attempt to lock that extent buffer through a
relocation tree we have to reset the lockdep class to the class for a
relocation tree, since a relocation tree has extent buffers that used
to belong to a fs tree and may currently be already loaded (we swap
extent buffers between the two trees at the end of replace_path()).

However we are missing calls to btrfs_maybe_reset_lockdep_class() to reset
the lockdep class at ctree.c:read_block_for_search() before we read lock
an extent buffer, just like we did for btrfs_search_slot() in commit
b40130b ("btrfs: fix lockdep splat with reloc root extent buffers").

So add the missing btrfs_maybe_reset_lockdep_class() calls before the
attempts to read lock an extent buffer at ctree.c:read_block_for_search().

The lockdep splat was reported by syzbot and it looks like this:

   ======================================================
   WARNING: possible circular locking dependency detected
   6.13.0-rc5-syzkaller-00163-gab75170520d4 #0 Not tainted
   ------------------------------------------------------
   syz.0.0/5335 is trying to acquire lock:
   ffff8880545dbc38 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146

   but task is already holding lock:
   ffff8880545dba58 (btrfs-treloc-02/1){+.+.}-{4:4}, at: btrfs_tree_lock_nested+0x2f/0x250 fs/btrfs/locking.c:189

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #2 (btrfs-treloc-02/1){+.+.}-{4:4}:
          reacquire_held_locks+0x3eb/0x690 kernel/locking/lockdep.c:5374
          __lock_release kernel/locking/lockdep.c:5563 [inline]
          lock_release+0x396/0xa30 kernel/locking/lockdep.c:5870
          up_write+0x79/0x590 kernel/locking/rwsem.c:1629
          btrfs_force_cow_block+0x14b3/0x1fd0 fs/btrfs/ctree.c:660
          btrfs_cow_block+0x371/0x830 fs/btrfs/ctree.c:755
          btrfs_search_slot+0xc01/0x3180 fs/btrfs/ctree.c:2153
          replace_path+0x1243/0x2740 fs/btrfs/relocation.c:1224
          merge_reloc_root+0xc46/0x1ad0 fs/btrfs/relocation.c:1692
          merge_reloc_roots+0x3b3/0x980 fs/btrfs/relocation.c:1942
          relocate_block_group+0xb0a/0xd40 fs/btrfs/relocation.c:3754
          btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087
          btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494
          __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278
          btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655
          btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670
          vfs_ioctl fs/ioctl.c:51 [inline]
          __do_sys_ioctl fs/ioctl.c:906 [inline]
          __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
          do_syscall_x64 arch/x86/entry/common.c:52 [inline]
          do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
          entry_SYSCALL_64_after_hwframe+0x77/0x7f

   -> #1 (btrfs-tree-01/1){+.+.}-{4:4}:
          lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
          down_write_nested+0xa2/0x220 kernel/locking/rwsem.c:1693
          btrfs_tree_lock_nested+0x2f/0x250 fs/btrfs/locking.c:189
          btrfs_init_new_buffer fs/btrfs/extent-tree.c:5052 [inline]
          btrfs_alloc_tree_block+0x41c/0x1440 fs/btrfs/extent-tree.c:5132
          btrfs_force_cow_block+0x526/0x1fd0 fs/btrfs/ctree.c:573
          btrfs_cow_block+0x371/0x830 fs/btrfs/ctree.c:755
          btrfs_search_slot+0xc01/0x3180 fs/btrfs/ctree.c:2153
          btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4351
          btrfs_insert_empty_item fs/btrfs/ctree.h:688 [inline]
          btrfs_insert_inode_ref+0x2bb/0xf80 fs/btrfs/inode-item.c:330
          btrfs_rename_exchange fs/btrfs/inode.c:7990 [inline]
          btrfs_rename2+0xcb7/0x2b90 fs/btrfs/inode.c:8374
          vfs_rename+0xbdb/0xf00 fs/namei.c:5067
          do_renameat2+0xd94/0x13f0 fs/namei.c:5224
          __do_sys_renameat2 fs/namei.c:5258 [inline]
          __se_sys_renameat2 fs/namei.c:5255 [inline]
          __x64_sys_renameat2+0xce/0xe0 fs/namei.c:5255
          do_syscall_x64 arch/x86/entry/common.c:52 [inline]
          do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
          entry_SYSCALL_64_after_hwframe+0x77/0x7f

   -> #0 (btrfs-tree-01){++++}-{4:4}:
          check_prev_add kernel/locking/lockdep.c:3161 [inline]
          check_prevs_add kernel/locking/lockdep.c:3280 [inline]
          validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
          __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
          lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
          down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1649
          btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146
          btrfs_tree_read_lock fs/btrfs/locking.h:188 [inline]
          read_block_for_search+0x718/0xbb0 fs/btrfs/ctree.c:1610
          btrfs_search_slot+0x1274/0x3180 fs/btrfs/ctree.c:2237
          replace_path+0x1243/0x2740 fs/btrfs/relocation.c:1224
          merge_reloc_root+0xc46/0x1ad0 fs/btrfs/relocation.c:1692
          merge_reloc_roots+0x3b3/0x980 fs/btrfs/relocation.c:1942
          relocate_block_group+0xb0a/0xd40 fs/btrfs/relocation.c:3754
          btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087
          btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494
          __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278
          btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655
          btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670
          vfs_ioctl fs/ioctl.c:51 [inline]
          __do_sys_ioctl fs/ioctl.c:906 [inline]
          __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
          do_syscall_x64 arch/x86/entry/common.c:52 [inline]
          do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
          entry_SYSCALL_64_after_hwframe+0x77/0x7f

   other info that might help us debug this:

   Chain exists of:
     btrfs-tree-01 --> btrfs-tree-01/1 --> btrfs-treloc-02/1

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(btrfs-treloc-02/1);
                                  lock(btrfs-tree-01/1);
                                  lock(btrfs-treloc-02/1);
     rlock(btrfs-tree-01);

    *** DEADLOCK ***

   8 locks held by syz.0.0/5335:
    #0: ffff88801e3ae420 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5e/0x200 fs/namespace.c:559
    #1: ffff888052c760d0 (&fs_info->reclaim_bgs_lock){+.+.}-{4:4}, at: __btrfs_balance+0x4c2/0x26b0 fs/btrfs/volumes.c:4183
    #2: ffff888052c74850 (&fs_info->cleaner_mutex){+.+.}-{4:4}, at: btrfs_relocate_block_group+0x775/0xd90 fs/btrfs/relocation.c:4086
    #3: ffff88801e3ae610 (sb_internal#2){.+.+}-{0:0}, at: merge_reloc_root+0xf11/0x1ad0 fs/btrfs/relocation.c:1659
    #4: ffff888052c76470 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x405/0xda0 fs/btrfs/transaction.c:288
    #5: ffff888052c76498 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x405/0xda0 fs/btrfs/transaction.c:288
    #6: ffff8880545db878 (btrfs-tree-01/1){+.+.}-{4:4}, at: btrfs_tree_lock_nested+0x2f/0x250 fs/btrfs/locking.c:189
    #7: ffff8880545dba58 (btrfs-treloc-02/1){+.+.}-{4:4}, at: btrfs_tree_lock_nested+0x2f/0x250 fs/btrfs/locking.c:189

   stack backtrace:
   CPU: 0 UID: 0 PID: 5335 Comm: syz.0.0 Not tainted 6.13.0-rc5-syzkaller-00163-gab75170520d4 #0
   Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
   Call Trace:
    <TASK>
    __dump_stack lib/dump_stack.c:94 [inline]
    dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
    print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
    check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
    check_prev_add kernel/locking/lockdep.c:3161 [inline]
    check_prevs_add kernel/locking/lockdep.c:3280 [inline]
    validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
    __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226
    lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849
    down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1649
    btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146
    btrfs_tree_read_lock fs/btrfs/locking.h:188 [inline]
    read_block_for_search+0x718/0xbb0 fs/btrfs/ctree.c:1610
    btrfs_search_slot+0x1274/0x3180 fs/btrfs/ctree.c:2237
    replace_path+0x1243/0x2740 fs/btrfs/relocation.c:1224
    merge_reloc_root+0xc46/0x1ad0 fs/btrfs/relocation.c:1692
    merge_reloc_roots+0x3b3/0x980 fs/btrfs/relocation.c:1942
    relocate_block_group+0xb0a/0xd40 fs/btrfs/relocation.c:3754
    btrfs_relocate_block_group+0x77d/0xd90 fs/btrfs/relocation.c:4087
    btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3494
    __btrfs_balance+0x1b0f/0x26b0 fs/btrfs/volumes.c:4278
    btrfs_balance+0xbdc/0x10c0 fs/btrfs/volumes.c:4655
    btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3670
    vfs_ioctl fs/ioctl.c:51 [inline]
    __do_sys_ioctl fs/ioctl.c:906 [inline]
    __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892
    do_syscall_x64 arch/x86/entry/common.c:52 [inline]
    do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
    entry_SYSCALL_64_after_hwframe+0x77/0x7f
   RIP: 0033:0x7f1ac6985d29
   Code: ff ff c3 (...)
   RSP: 002b:00007f1ac63fe038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
   RAX: ffffffffffffffda RBX: 00007f1ac6b76160 RCX: 00007f1ac6985d29
   RDX: 0000000020000180 RSI: 00000000c4009420 RDI: 0000000000000007
   RBP: 00007f1ac6a01b08 R08: 0000000000000000 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   R13: 0000000000000001 R14: 00007f1ac6b76160 R15: 00007fffda145a88
    </TASK>

Reported-by: syzbot+63913e558c084f7f8fdc@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/677b3014.050a0220.3b53b0.0064.GAE@google.com/
Fixes: 9978599 ("btrfs: reduce lock contention when eb cache miss for btree search")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
pull bot pushed a commit that referenced this pull request Feb 16, 2025
We have several places across the kernel where we want to access another
task's syscall arguments, such as ptrace(2), seccomp(2), etc., by making
a call to syscall_get_arguments().

This works for register arguments right away by accessing the task's
`regs' member of `struct pt_regs', however for stack arguments seen with
32-bit/o32 kernels things are more complicated.  Technically they ought
to be obtained from the user stack with calls to an access_remote_vm(),
but we have an easier way available already.

So as to be able to access syscall stack arguments as regular function
arguments following the MIPS calling convention we copy them over from
the user stack to the kernel stack in arch/mips/kernel/scall32-o32.S, in
handle_sys(), to the current stack frame's outgoing argument space at
the top of the stack, which is where the handler called expects to see
its incoming arguments.  This area is also pointed at by the `pt_regs'
pointer obtained by task_pt_regs().

Make the o32 stack argument space a proper member of `struct pt_regs'
then, by renaming the existing member from `pad0' to `args' and using
generated offsets to access the space.  No functional change though.

With the change in place the o32 kernel stack frame layout at the entry
to a syscall handler invoked by handle_sys() is therefore as follows:

$sp + 68 -> |         ...         | <- pt_regs.regs[9]
            +---------------------+
$sp + 64 -> |         $t0         | <- pt_regs.regs[8]
            +---------------------+
$sp + 60 -> |   $a3/argument #4   | <- pt_regs.regs[7]
            +---------------------+
$sp + 56 -> |   $a2/argument #3   | <- pt_regs.regs[6]
            +---------------------+
$sp + 52 -> |   $a1/argument #2   | <- pt_regs.regs[5]
            +---------------------+
$sp + 48 -> |   $a0/argument #1   | <- pt_regs.regs[4]
            +---------------------+
$sp + 44 -> |         $v1         | <- pt_regs.regs[3]
            +---------------------+
$sp + 40 -> |         $v0         | <- pt_regs.regs[2]
            +---------------------+
$sp + 36 -> |         $at         | <- pt_regs.regs[1]
            +---------------------+
$sp + 32 -> |        $zero        | <- pt_regs.regs[0]
            +---------------------+
$sp + 28 -> |  stack argument #8  | <- pt_regs.args[7]
            +---------------------+
$sp + 24 -> |  stack argument #7  | <- pt_regs.args[6]
            +---------------------+
$sp + 20 -> |  stack argument #6  | <- pt_regs.args[5]
            +---------------------+
$sp + 16 -> |  stack argument #5  | <- pt_regs.args[4]
            +---------------------+
$sp + 12 -> | psABI space for $a3 | <- pt_regs.args[3]
            +---------------------+
$sp +  8 -> | psABI space for $a2 | <- pt_regs.args[2]
            +---------------------+
$sp +  4 -> | psABI space for $a1 | <- pt_regs.args[1]
            +---------------------+
$sp +  0 -> | psABI space for $a0 | <- pt_regs.args[0]
            +---------------------+

holding user data received and with the first 4 frame slots reserved by
the psABI for the compiler to spill the incoming arguments from $a0-$a3
registers (which it sometimes does according to its needs) and the next
4 frame slots designated by the psABI for any stack function arguments
that follow.  This data is also available for other tasks to peek/poke
at as reqired and where permitted.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
pull bot pushed a commit that referenced this pull request Feb 16, 2025
This makes ptrace/get_syscall_info selftest pass on mips o32 and
mips64 o32 by fixing the following two test assertions:

1. get_syscall_info test assertion on mips o32:
  # get_syscall_info.c:218:get_syscall_info:Expected exp_args[5] (3134521044) == info.entry.args[4] (4911432)
  # get_syscall_info.c:219:get_syscall_info:wait #1: entry stop mismatch

2. get_syscall_info test assertion on mips64 o32:
  # get_syscall_info.c:209:get_syscall_info:Expected exp_args[2] (3134324433) == info.entry.args[1] (18446744072548908753)
  # get_syscall_info.c:210:get_syscall_info:wait #1: entry stop mismatch

The first assertion happens due to mips_get_syscall_arg() trying to access
another task's context but failing to do it properly because get_user() it
calls just peeks at the current task's context.  It usually does not crash
because the default user stack always gets assigned the same VMA, but it
is pure luck which mips_get_syscall_arg() wouldn't have if e.g. the stack
was switched (via setcontext(3) or however) or a non-default process's
thread peeked at, and in any case irrelevant data is obtained just as
observed with the test case.

mips_get_syscall_arg() ought to be using access_remote_vm() instead to
retrieve the other task's stack contents, but given that the data has been
already obtained and saved in `struct pt_regs' it would be an overkill.

The first assertion is fixed for mips o32 by using struct pt_regs.args
instead of get_user() to obtain syscall arguments.  This approach works
due to this piece in arch/mips/kernel/scall32-o32.S:

        /*
         * Ok, copy the args from the luser stack to the kernel stack.
         */

        .set    push
        .set    noreorder
        .set    nomacro

    load_a4: user_lw(t5, 16(t0))		# argument #5 from usp
    load_a5: user_lw(t6, 20(t0))		# argument #6 from usp
    load_a6: user_lw(t7, 24(t0))		# argument #7 from usp
    load_a7: user_lw(t8, 28(t0))		# argument #8 from usp
    loads_done:

        sw	t5, PT_ARG4(sp)		# argument #5 to ksp
        sw	t6, PT_ARG5(sp)		# argument #6 to ksp
        sw	t7, PT_ARG6(sp)		# argument #7 to ksp
        sw	t8, PT_ARG7(sp)		# argument #8 to ksp
        .set	pop

        .section __ex_table,"a"
        PTR_WD	load_a4, bad_stack_a4
        PTR_WD	load_a5, bad_stack_a5
        PTR_WD	load_a6, bad_stack_a6
        PTR_WD	load_a7, bad_stack_a7
        .previous

arch/mips/kernel/scall64-o32.S has analogous code for mips64 o32 that
allows fixing the issue by obtaining syscall arguments from struct
pt_regs.regs[4..11] instead of the erroneous use of get_user().

The second assertion is fixed by truncating 64-bit values to 32-bit
syscall arguments.

Fixes: c0ff3c5 ("MIPS: Enable HAVE_ARCH_TRACEHOOK.")
Signed-off-by: Dmitry V. Levin <ldv@strace.io>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
pull bot pushed a commit that referenced this pull request Mar 27, 2025
In recent kernels, there are lockdep splats around the
struct request_queue::io_lockdep_map, similar to [1], but they
typically don't show up until reclaim with writeback happens.

Having multiple kernel versions released with a known risc of kernel
deadlock during reclaim writeback should IMHO be addressed and
backported to -stable with the highest priority.

In order to have these lockdep splats show up earlier,
preferrably during system initialization, prime the
struct request_queue::io_lockdep_map as GFP_KERNEL reclaim-
tainted. This will instead lead to lockdep splats looking similar
to [2], but without the need for reclaim + writeback
happening.

[1]:
[  189.762244] ======================================================
[  189.762432] WARNING: possible circular locking dependency detected
[  189.762441] 6.14.0-rc6-xe+ #6 Tainted: G     U
[  189.762450] ------------------------------------------------------
[  189.762459] kswapd0/119 is trying to acquire lock:
[  189.762467] ffff888110ceb710 (&q->q_usage_counter(io)#26){++++}-{0:0}, at: __submit_bio+0x76/0x230
[  189.762485]
               but task is already holding lock:
[  189.762494] ffffffff834c97c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xbe/0xb00
[  189.762507]
               which lock already depends on the new lock.

[  189.762519]
               the existing dependency chain (in reverse order) is:
[  189.762529]
               -> #2 (fs_reclaim){+.+.}-{0:0}:
[  189.762540]        fs_reclaim_acquire+0xc5/0x100
[  189.762548]        kmem_cache_alloc_lru_noprof+0x4a/0x480
[  189.762558]        alloc_inode+0xaa/0xe0
[  189.762566]        iget_locked+0x157/0x330
[  189.762573]        kernfs_get_inode+0x1b/0x110
[  189.762582]        kernfs_get_tree+0x1b0/0x2e0
[  189.762590]        sysfs_get_tree+0x1f/0x60
[  189.762597]        vfs_get_tree+0x2a/0xf0
[  189.762605]        path_mount+0x4cd/0xc00
[  189.762613]        __x64_sys_mount+0x119/0x150
[  189.762621]        x64_sys_call+0x14f2/0x2310
[  189.762630]        do_syscall_64+0x91/0x180
[  189.762637]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  189.762647]
               -> #1 (&root->kernfs_rwsem){++++}-{3:3}:
[  189.762659]        down_write+0x3e/0xf0
[  189.762667]        kernfs_remove+0x32/0x60
[  189.762676]        sysfs_remove_dir+0x4f/0x60
[  189.762685]        __kobject_del+0x33/0xa0
[  189.762709]        kobject_del+0x13/0x30
[  189.762716]        elv_unregister_queue+0x52/0x80
[  189.762725]        elevator_switch+0x68/0x360
[  189.762733]        elv_iosched_store+0x14b/0x1b0
[  189.762756]        queue_attr_store+0x181/0x1e0
[  189.762765]        sysfs_kf_write+0x49/0x80
[  189.762773]        kernfs_fop_write_iter+0x17d/0x250
[  189.762781]        vfs_write+0x281/0x540
[  189.762790]        ksys_write+0x72/0xf0
[  189.762798]        __x64_sys_write+0x19/0x30
[  189.762807]        x64_sys_call+0x2a3/0x2310
[  189.762815]        do_syscall_64+0x91/0x180
[  189.762823]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  189.762833]
               -> #0 (&q->q_usage_counter(io)#26){++++}-{0:0}:
[  189.762845]        __lock_acquire+0x1525/0x2760
[  189.762854]        lock_acquire+0xca/0x310
[  189.762861]        blk_mq_submit_bio+0x8a2/0xba0
[  189.762870]        __submit_bio+0x76/0x230
[  189.762878]        submit_bio_noacct_nocheck+0x323/0x430
[  189.762888]        submit_bio_noacct+0x2cc/0x620
[  189.762896]        submit_bio+0x38/0x110
[  189.762904]        __swap_writepage+0xf5/0x380
[  189.762912]        swap_writepage+0x3c7/0x600
[  189.762920]        shmem_writepage+0x3da/0x4f0
[  189.762929]        pageout+0x13f/0x310
[  189.762937]        shrink_folio_list+0x61c/0xf60
[  189.763261]        evict_folios+0x378/0xcd0
[  189.763584]        try_to_shrink_lruvec+0x1b0/0x360
[  189.763946]        shrink_one+0x10e/0x200
[  189.764266]        shrink_node+0xc02/0x1490
[  189.764586]        balance_pgdat+0x563/0xb00
[  189.764934]        kswapd+0x1e8/0x430
[  189.765249]        kthread+0x10b/0x260
[  189.765559]        ret_from_fork+0x44/0x70
[  189.765889]        ret_from_fork_asm+0x1a/0x30
[  189.766198]
               other info that might help us debug this:

[  189.767089] Chain exists of:
                 &q->q_usage_counter(io)#26 --> &root->kernfs_rwsem --> fs_reclaim

[  189.767971]  Possible unsafe locking scenario:

[  189.768555]        CPU0                    CPU1
[  189.768849]        ----                    ----
[  189.769136]   lock(fs_reclaim);
[  189.769421]                                lock(&root->kernfs_rwsem);
[  189.769714]                                lock(fs_reclaim);
[  189.770016]   rlock(&q->q_usage_counter(io)#26);
[  189.770305]
                *** DEADLOCK ***

[  189.771167] 1 lock held by kswapd0/119:
[  189.771453]  #0: ffffffff834c97c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xbe/0xb00
[  189.771770]
               stack backtrace:
[  189.772351] CPU: 4 UID: 0 PID: 119 Comm: kswapd0 Tainted: G     U             6.14.0-rc6-xe+ #6
[  189.772353] Tainted: [U]=USER
[  189.772354] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[  189.772354] Call Trace:
[  189.772355]  <TASK>
[  189.772356]  dump_stack_lvl+0x6e/0xa0
[  189.772359]  dump_stack+0x10/0x18
[  189.772360]  print_circular_bug.cold+0x17a/0x1b7
[  189.772363]  check_noncircular+0x13a/0x150
[  189.772365]  ? __pfx_stack_trace_consume_entry+0x10/0x10
[  189.772368]  __lock_acquire+0x1525/0x2760
[  189.772368]  ? ret_from_fork_asm+0x1a/0x30
[  189.772371]  lock_acquire+0xca/0x310
[  189.772372]  ? __submit_bio+0x76/0x230
[  189.772375]  ? lock_release+0xd5/0x2c0
[  189.772376]  blk_mq_submit_bio+0x8a2/0xba0
[  189.772378]  ? __submit_bio+0x76/0x230
[  189.772380]  __submit_bio+0x76/0x230
[  189.772382]  ? trace_hardirqs_on+0x1e/0xe0
[  189.772384]  submit_bio_noacct_nocheck+0x323/0x430
[  189.772386]  ? submit_bio_noacct_nocheck+0x323/0x430
[  189.772387]  ? __might_sleep+0x58/0xa0
[  189.772390]  submit_bio_noacct+0x2cc/0x620
[  189.772391]  ? count_memcg_events+0x68/0x90
[  189.772393]  submit_bio+0x38/0x110
[  189.772395]  __swap_writepage+0xf5/0x380
[  189.772396]  swap_writepage+0x3c7/0x600
[  189.772397]  shmem_writepage+0x3da/0x4f0
[  189.772401]  pageout+0x13f/0x310
[  189.772406]  shrink_folio_list+0x61c/0xf60
[  189.772409]  ? isolate_folios+0xe80/0x16b0
[  189.772410]  ? mark_held_locks+0x46/0x90
[  189.772412]  evict_folios+0x378/0xcd0
[  189.772414]  ? evict_folios+0x34a/0xcd0
[  189.772415]  ? lock_is_held_type+0xa3/0x130
[  189.772417]  try_to_shrink_lruvec+0x1b0/0x360
[  189.772420]  shrink_one+0x10e/0x200
[  189.772421]  shrink_node+0xc02/0x1490
[  189.772423]  ? shrink_node+0xa08/0x1490
[  189.772424]  ? shrink_node+0xbd8/0x1490
[  189.772425]  ? mem_cgroup_iter+0x366/0x480
[  189.772427]  balance_pgdat+0x563/0xb00
[  189.772428]  ? balance_pgdat+0x563/0xb00
[  189.772430]  ? trace_hardirqs_on+0x1e/0xe0
[  189.772431]  ? finish_task_switch.isra.0+0xcb/0x330
[  189.772433]  ? __switch_to_asm+0x33/0x70
[  189.772437]  kswapd+0x1e8/0x430
[  189.772438]  ? __pfx_autoremove_wake_function+0x10/0x10
[  189.772440]  ? __pfx_kswapd+0x10/0x10
[  189.772441]  kthread+0x10b/0x260
[  189.772443]  ? __pfx_kthread+0x10/0x10
[  189.772444]  ret_from_fork+0x44/0x70
[  189.772446]  ? __pfx_kthread+0x10/0x10
[  189.772447]  ret_from_fork_asm+0x1a/0x30
[  189.772450]  </TASK>

[2]:
[    8.760253] ======================================================
[    8.760254] WARNING: possible circular locking dependency detected
[    8.760255] 6.14.0-rc6-xe+ #7 Tainted: G     U
[    8.760256] ------------------------------------------------------
[    8.760257] (udev-worker)/674 is trying to acquire lock:
[    8.760259] ffff888100e39148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_remove+0x32/0x60
[    8.760265]
               but task is already holding lock:
[    8.760266] ffff888110dc7680 (&q->q_usage_counter(io)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30
[    8.760272]
               which lock already depends on the new lock.

[    8.760272]
               the existing dependency chain (in reverse order) is:
[    8.760273]
               -> #2 (&q->q_usage_counter(io)#27){++++}-{0:0}:
[    8.760276]        blk_alloc_queue+0x30a/0x350
[    8.760279]        blk_mq_alloc_queue+0x6b/0xe0
[    8.760281]        scsi_alloc_sdev+0x276/0x3c0
[    8.760284]        scsi_probe_and_add_lun+0x22a/0x440
[    8.760286]        __scsi_scan_target+0x109/0x230
[    8.760288]        scsi_scan_channel+0x65/0xc0
[    8.760290]        scsi_scan_host_selected+0xff/0x140
[    8.760292]        do_scsi_scan_host+0xa7/0xc0
[    8.760293]        do_scan_async+0x1c/0x160
[    8.760295]        async_run_entry_fn+0x32/0x150
[    8.760299]        process_one_work+0x224/0x5f0
[    8.760302]        worker_thread+0x1d4/0x3e0
[    8.760304]        kthread+0x10b/0x260
[    8.760306]        ret_from_fork+0x44/0x70
[    8.760309]        ret_from_fork_asm+0x1a/0x30
[    8.760312]
               -> #1 (fs_reclaim){+.+.}-{0:0}:
[    8.760315]        fs_reclaim_acquire+0xc5/0x100
[    8.760317]        kmem_cache_alloc_lru_noprof+0x4a/0x480
[    8.760319]        alloc_inode+0xaa/0xe0
[    8.760322]        iget_locked+0x157/0x330
[    8.760323]        kernfs_get_inode+0x1b/0x110
[    8.760325]        kernfs_get_tree+0x1b0/0x2e0
[    8.760327]        sysfs_get_tree+0x1f/0x60
[    8.760329]        vfs_get_tree+0x2a/0xf0
[    8.760332]        path_mount+0x4cd/0xc00
[    8.760334]        __x64_sys_mount+0x119/0x150
[    8.760336]        x64_sys_call+0x14f2/0x2310
[    8.760338]        do_syscall_64+0x91/0x180
[    8.760340]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    8.760342]
               -> #0 (&root->kernfs_rwsem){++++}-{3:3}:
[    8.760345]        __lock_acquire+0x1525/0x2760
[    8.760347]        lock_acquire+0xca/0x310
[    8.760348]        down_write+0x3e/0xf0
[    8.760350]        kernfs_remove+0x32/0x60
[    8.760351]        sysfs_remove_dir+0x4f/0x60
[    8.760353]        __kobject_del+0x33/0xa0
[    8.760355]        kobject_del+0x13/0x30
[    8.760356]        elv_unregister_queue+0x52/0x80
[    8.760358]        elevator_switch+0x68/0x360
[    8.760360]        elv_iosched_store+0x14b/0x1b0
[    8.760362]        queue_attr_store+0x181/0x1e0
[    8.760364]        sysfs_kf_write+0x49/0x80
[    8.760366]        kernfs_fop_write_iter+0x17d/0x250
[    8.760367]        vfs_write+0x281/0x540
[    8.760370]        ksys_write+0x72/0xf0
[    8.760372]        __x64_sys_write+0x19/0x30
[    8.760374]        x64_sys_call+0x2a3/0x2310
[    8.760376]        do_syscall_64+0x91/0x180
[    8.760377]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    8.760380]
               other info that might help us debug this:

[    8.760380] Chain exists of:
                 &root->kernfs_rwsem --> fs_reclaim --> &q->q_usage_counter(io)#27

[    8.760384]  Possible unsafe locking scenario:

[    8.760384]        CPU0                    CPU1
[    8.760385]        ----                    ----
[    8.760385]   lock(&q->q_usage_counter(io)#27);
[    8.760387]                                lock(fs_reclaim);
[    8.760388]                                lock(&q->q_usage_counter(io)#27);
[    8.760390]   lock(&root->kernfs_rwsem);
[    8.760391]
                *** DEADLOCK ***

[    8.760391] 6 locks held by (udev-worker)/674:
[    8.760392]  #0: ffff8881209ac420 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0x72/0xf0
[    8.760398]  #1: ffff88810c80f488 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x136/0x250
[    8.760402]  #2: ffff888125d1d330 (kn->active#101){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x13f/0x250
[    8.760406]  #3: ffff888110dc7bb0 (&q->sysfs_lock){+.+.}-{3:3}, at: queue_attr_store+0x148/0x1e0
[    8.760411]  #4: ffff888110dc7680 (&q->q_usage_counter(io)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30
[    8.760416]  #5: ffff888110dc76b8 (&q->q_usage_counter(queue)#27){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x12/0x30
[    8.760421]
               stack backtrace:
[    8.760422] CPU: 7 UID: 0 PID: 674 Comm: (udev-worker) Tainted: G     U             6.14.0-rc6-xe+ #7
[    8.760424] Tainted: [U]=USER
[    8.760425] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[    8.760426] Call Trace:
[    8.760427]  <TASK>
[    8.760428]  dump_stack_lvl+0x6e/0xa0
[    8.760431]  dump_stack+0x10/0x18
[    8.760433]  print_circular_bug.cold+0x17a/0x1b7
[    8.760437]  check_noncircular+0x13a/0x150
[    8.760441]  ? save_trace+0x54/0x360
[    8.760445]  __lock_acquire+0x1525/0x2760
[    8.760446]  ? irqentry_exit+0x3a/0xb0
[    8.760448]  ? sysvec_apic_timer_interrupt+0x57/0xc0
[    8.760452]  lock_acquire+0xca/0x310
[    8.760453]  ? kernfs_remove+0x32/0x60
[    8.760457]  down_write+0x3e/0xf0
[    8.760459]  ? kernfs_remove+0x32/0x60
[    8.760460]  kernfs_remove+0x32/0x60
[    8.760462]  sysfs_remove_dir+0x4f/0x60
[    8.760464]  __kobject_del+0x33/0xa0
[    8.760466]  kobject_del+0x13/0x30
[    8.760467]  elv_unregister_queue+0x52/0x80
[    8.760470]  elevator_switch+0x68/0x360
[    8.760472]  elv_iosched_store+0x14b/0x1b0
[    8.760475]  queue_attr_store+0x181/0x1e0
[    8.760479]  ? lock_acquire+0xca/0x310
[    8.760480]  ? kernfs_fop_write_iter+0x13f/0x250
[    8.760482]  ? lock_is_held_type+0xa3/0x130
[    8.760485]  sysfs_kf_write+0x49/0x80
[    8.760487]  kernfs_fop_write_iter+0x17d/0x250
[    8.760489]  vfs_write+0x281/0x540
[    8.760494]  ksys_write+0x72/0xf0
[    8.760497]  __x64_sys_write+0x19/0x30
[    8.760499]  x64_sys_call+0x2a3/0x2310
[    8.760502]  do_syscall_64+0x91/0x180
[    8.760504]  ? trace_hardirqs_off+0x5d/0xe0
[    8.760506]  ? handle_softirqs+0x479/0x4d0
[    8.760508]  ? hrtimer_interrupt+0x13f/0x280
[    8.760511]  ? irqentry_exit_to_user_mode+0x8b/0x260
[    8.760513]  ? clear_bhb_loop+0x15/0x70
[    8.760515]  ? clear_bhb_loop+0x15/0x70
[    8.760516]  ? clear_bhb_loop+0x15/0x70
[    8.760518]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    8.760520] RIP: 0033:0x7aa3bf2f5504
[    8.760522] Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d c5 8b 10 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
[    8.760523] RSP: 002b:00007ffc1e3697d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[    8.760526] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007aa3bf2f5504
[    8.760527] RDX: 0000000000000003 RSI: 00007ffc1e369ae0 RDI: 000000000000001c
[    8.760528] RBP: 00007ffc1e369800 R08: 00007aa3bf3f51c8 R09: 00007ffc1e3698b0
[    8.760528] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
[    8.760529] R13: 00007ffc1e369ae0 R14: 0000613ccf21f2f0 R15: 00007aa3bf3f4e80
[    8.760533]  </TASK>

v2:
- Update a code comment to increase readability (Ming Lei).

Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250318095548.5187-1-thomas.hellstrom@linux.intel.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
pull bot pushed a commit that referenced this pull request Mar 27, 2025
Chia-Yu Chang says:

====================
AccECN protocol preparation patch series

Please find the v7

v7 (03-Mar-2025)
- Move 2 new patches added in v6 to the next AccECN patch series

v6 (27-Dec-2024)
- Avoid removing removing the potential CA_ACK_WIN_UPDATE in ack_ev_flags of patch #1 (Eric Dumazet <edumazet@google.com>)
- Add reviewed-by tag in patches #2, #3, #4, #5, #6, #7, #8, #12, #14
- Foloiwng 2 new pathces are added after patch #9 (Patch that adds SKB_GSO_TCP_ACCECN)
  * New patch #10 to replace exisiting SKB_GSO_TCP_ECN with SKB_GSO_TCP_ACCECN in the driver to avoid CWR flag corruption
  * New patch #11 adds AccECN for virtio by adding new negotiation flag (VIRTIO_NET_F_HOST/GUEST_ACCECN) in feature handshake and translating Accurate ECN GSO flag between virtio_net_hdr (VIRTIO_NET_HDR_GSO_ACCECN) and skb header (SKB_GSO_TCP_ACCECN)
- Add detailed changelog and comments in #13 (Eric Dumazet <edumazet@google.com>)
- Move patch #14 to the next AccECN patch series (Eric Dumazet <edumazet@google.com>)

v5 (5-Nov-2024)
- Add helper function "tcp_flags_ntohs" to preserve last 2 bytes of TCP flags of patch #4 (Paolo Abeni <pabeni@redhat.com>)
- Fix reverse X-max tree order of patches #4, #11 (Paolo Abeni <pabeni@redhat.com>)
- Rename variable "delta" as "timestamp_delta" of patch #2 fo clariety
- Remove patch #14 in this series (Paolo Abeni <pabeni@redhat.com>, Joel Granados <joel.granados@kernel.org>)

v4 (21-Oct-2024)
- Fix line length warning of patches #2, #4, #8, #10, #11, #14
- Fix spaces preferred around '|' (ctx:VxV) warning of patch #7
- Add missing CC'ed of patches #4, #12, #14

v3 (19-Oct-2024)
- Fix build error in v2

v2 (18-Oct-2024)
- Fix warning caused by NETIF_F_GSO_ACCECN_BIT in patch #9 (Jakub Kicinski <kuba@kernel.org>)

The full patch series can be found in
https://github.com/L4STeam/linux-net-next/commits/upstream_l4steam/

The Accurate ECN draft can be found in
https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-accurate-ecn-28
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
pull bot pushed a commit that referenced this pull request Mar 27, 2025
Fixes the following:

[   17.607394] kernel BUG at fs/bcachefs/reflink.c:261!
[   17.608316] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[   17.608485] CPU: 0 UID: 0 PID: 564 Comm: bch-rebalance/3 Tainted: G           OE      6.14.0-rc6-arch1-gfcb0bd9609d2 #7 0efd7a8f4a00afeb2c5fb6e7ecb1aec8ddcbb1e1
[   17.608616] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[   17.608736] Hardware name: Micro-Star International Co., Ltd. MS-7D75/MAG B650 TOMAHAWK WIFI (MS-7D75), BIOS 1.74 08/01/2023
[   17.608855] RIP: 0010:bch2_lookup_indirect_extent+0x252/0x290 [bcachefs]
[   17.609006] Code: 00 00 00 00 e8 7f 51 f5 ff 89 c3 85 c0 74 52 48 8b 7d b0 4c 89 ee e8 4d 4b f4 ff 48 63 d3 48 89 d0 31 d2 e9 2e ff ff ff 0f 0b <0f> 0b 48 8b 7d b0 4c 89 ee 48 89 55 a8 e8 2c 4b f4 ff 4c 8b 55 a8
[   17.609136] RSP: 0018:ffffa3714455f850 EFLAGS: 00010246
[   17.609261] RAX: 0000000000000080 RBX: ffff895891098790 RCX: 0000000000000000
[   17.609387] RDX: 0000000000000080 RSI: ffffa3714455fa90 RDI: ffff895889550000
[   17.609511] RBP: ffffa3714455f8c0 R08: ffff895891098790 R09: 0000000000000001
[   17.609637] R10: ffffa3714455f8d8 R11: ffffa3714455f950 R12: ffffa3714455fa58
[   17.609763] R13: ffff895891098790 R14: ffffa3714455fa58 R15: ffff895889550000
[   17.609888] FS:  0000000000000000(0000) GS:ffff896757c00000(0000) knlGS:0000000000000000
[   17.610015] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   17.610143] CR2: 0000716b8cda2750 CR3: 0000000914e22000 CR4: 0000000000f50ef0
[   17.610272] PKRU: 55555554
[   17.610403] Call Trace:
[   17.610535]  <TASK>
[   17.610662]  ? __die_body.cold+0x19/0x27
[   17.610791]  ? die+0x2e/0x50
[   17.610918]  ? do_trap+0xca/0x110
[   17.611049]  ? do_error_trap+0x6a/0x90
[   17.611178]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611331]  ? exc_invalid_op+0x50/0x70
[   17.611468]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611620]  ? asm_exc_invalid_op+0x1a/0x20
[   17.611757]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611911]  ? bch2_move_data_btree+0x58a/0x6c0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612084]  bch2_move_data_btree+0x58a/0x6c0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612256]  ? __pfx_rebalance_pred+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612431]  ? bch2_move_extent+0x3d7/0x6e0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612607]  ? __bch2_move_data+0xea/0x200 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612782]  __bch2_move_data+0xea/0x200 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612959]  ? __pfx_rebalance_pred+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613149]  do_rebalance+0x517/0x8d0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613342]  ? local_clock_noinstr+0xd/0xd0
[   17.613518]  ? local_clock+0x15/0x30
[   17.613693]  ? __bch2_trans_get+0x152/0x300 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613890]  ? __pfx_bch2_rebalance_thread+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.614090]  bch2_rebalance_thread+0x66/0xb0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]

The offset_into_extent bit was copied from the read path, but it's
unnecessary here, where we always want to read and move the entire
indirect extent, and it causes the assertion pop - because we're using a
non-extents iterator, which always points to the end of the reflink
pointer.

Reported-by: Maël Kerbiriou <mael.kerbiriou@free.fr>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
pull bot pushed a commit that referenced this pull request Mar 30, 2025
Eduard Zingerman says:

====================
This patch set fixes a bug in copy_verifier_state() where the
loop_entry field was not copied. This omission led to incorrect
loop_entry fields remaining in env->cur_state, causing incorrect
decisions about loop entry assignments in update_loop_entry().

An example of an unsafe program accepted by the verifier due to this
bug can be found in patch #2. This bug can also cause an infinite loop
in the verifier, see patch #5.

Structure of the patch set:
- Patch #1 fixes the bug but has a significant negative impact on
  verification performance for sched_ext programs.
- Patch #3 mitigates the verification performance impact of patch #1
  by avoiding clean_live_states() for states whose loop_entry is still
  being verified. This reduces the number of processed instructions
  for sched_ext programs by 28–92% in some cases.
- Patches #5-6 simplify {get,update}_loop_entry() logic (and are not
  strictly necessary).
- Patches #7–10 mitigate the memory overhead introduced by patch #1
  when a program with iterator-based loop hits the 1M instruction
  limit. This is achieved by freeing states in env->free_list when
  their branches and used_as_loop_entry counts reach zero.

Patches #1-4 were previously sent as a part of [1].

[1] https://lore.kernel.org/bpf/20250122120442.3536298-1-eddyz87@gmail.com/
====================

Link: https://patch.msgid.link/20250215110411.3236773-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
pull bot pushed a commit that referenced this pull request Mar 31, 2025
perf test 11 hwmon fails on s390 with this error

 # ./perf test -Fv 11
 --- start ---
 ---- end ----
 11.1: Basic parsing test             : Ok
 --- start ---
 Testing 'temp_test_hwmon_event1'
 Using CPUID IBM,3931,704,A01,3.7,002f
 temp_test_hwmon_event1 -> hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/
 FAILED tests/hwmon_pmu.c:189 Unexpected config for
    'temp_test_hwmon_event1', 292470092988416 != 655361
 ---- end ----
 11.2: Parsing without PMU name       : FAILED!
 --- start ---
 Testing 'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/'
 FAILED tests/hwmon_pmu.c:189 Unexpected config for
    'hwmon_a_test_hwmon_pmu/temp_test_hwmon_event1/',
    292470092988416 != 655361
 ---- end ----
 11.3: Parsing with PMU name          : FAILED!
 #

The root cause is in member test_event::config which is initialized
to 0xA0001 or 655361. During event parsing a long list event parsing
functions are called and end up with this gdb call stack:

 #0  hwmon_pmu__config_term (hwm=0x168dfd0, attr=0x3ffffff5ee8,
	term=0x168db60, err=0x3ffffff81c8) at util/hwmon_pmu.c:623
 #1  hwmon_pmu__config_terms (pmu=0x168dfd0, attr=0x3ffffff5ee8,
	terms=0x3ffffff5ea8, err=0x3ffffff81c8) at util/hwmon_pmu.c:662
 #2  0x00000000012f870c in perf_pmu__config_terms (pmu=0x168dfd0,
	attr=0x3ffffff5ee8, terms=0x3ffffff5ea8, zero=false,
	apply_hardcoded=false, err=0x3ffffff81c8) at util/pmu.c:1519
 #3  0x00000000012f88a4 in perf_pmu__config (pmu=0x168dfd0, attr=0x3ffffff5ee8,
	head_terms=0x3ffffff5ea8, apply_hardcoded=false, err=0x3ffffff81c8)
	at util/pmu.c:1545
 #4  0x00000000012680c4 in parse_events_add_pmu (parse_state=0x3ffffff7fb8,
	list=0x168dc00, pmu=0x168dfd0, const_parsed_terms=0x3ffffff6090,
	auto_merge_stats=true, alternate_hw_config=10)
	at util/parse-events.c:1508
 #5  0x00000000012684c6 in parse_events_multi_pmu_add (parse_state=0x3ffffff7fb8,
	event_name=0x168ec10 "temp_test_hwmon_event1", hw_config=10,
	const_parsed_terms=0x0, listp=0x3ffffff6230, loc_=0x3ffffff70e0)
	at util/parse-events.c:1592
 #6  0x00000000012f0e4e in parse_events_parse (_parse_state=0x3ffffff7fb8,
	scanner=0x16878c0) at util/parse-events.y:293
 #7  0x00000000012695a0 in parse_events__scanner (str=0x3ffffff81d8
	"temp_test_hwmon_event1", input=0x0, parse_state=0x3ffffff7fb8)
	at util/parse-events.c:1867
 #8  0x000000000126a1e8 in __parse_events (evlist=0x168b580,
	str=0x3ffffff81d8 "temp_test_hwmon_event1", pmu_filter=0x0,
	err=0x3ffffff81c8, fake_pmu=false, warn_if_reordered=true,
	fake_tp=false) at util/parse-events.c:2136
 #9  0x00000000011e36aa in parse_events (evlist=0x168b580,
	str=0x3ffffff81d8 "temp_test_hwmon_event1", err=0x3ffffff81c8)
	at /root/linux/tools/perf/util/parse-events.h:41
 #10 0x00000000011e3e64 in do_test (i=0, with_pmu=false, with_alias=false)
	at tests/hwmon_pmu.c:164
 #11 0x00000000011e422c in test__hwmon_pmu (with_pmu=false)
	at tests/hwmon_pmu.c:219
 #12 0x00000000011e431c in test__hwmon_pmu_without_pmu (test=0x1610368
	<suite.hwmon_pmu>, subtest=1) at tests/hwmon_pmu.c:23

where the attr::config is set to value 292470092988416 or 0x10a0000000000
in line 625 of file ./util/hwmon_pmu.c:

   attr->config = key.type_and_num;

However member key::type_and_num is defined as union and bit field:

   union hwmon_pmu_event_key {
        long type_and_num;
        struct {
                int num :16;
                enum hwmon_type type :8;
        };
   };

s390 is big endian and Intel is little endian architecture.
The events for the hwmon dummy pmu have num = 1 or num = 2 and
type is set to HWMON_TYPE_TEMP (which is 10).
On s390 this assignes member key::type_and_num the value of
0x10a0000000000 (which is 292470092988416) as shown in above
trace output.

Fix this and export the structure/union hwmon_pmu_event_key
so the test shares the same implementation as the event parsing
functions for union and bit fields. This should avoid
endianess issues on all platforms.

Output after:
 # ./perf test -F 11
 11.1: Basic parsing test         : Ok
 11.2: Parsing without PMU name   : Ok
 11.3: Parsing with PMU name      : Ok
 #

Fixes: 531ee0f ("perf test: Add hwmon "PMU" test")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250131112400.568975-1-tmricht@linux.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Mar 31, 2025
Ian told me that there are many memory leaks in the hierarchy mode.  I
can easily reproduce it with the follwing command.

  $ make DEBUG=1 EXTRA_CFLAGS=-fsanitize=leak

  $ perf record --latency -g -- ./perf test -w thloop

  $ perf report -H --stdio
  ...
  Indirect leak of 168 byte(s) in 21 object(s) allocated from:
      #0 0x7f3414c16c65 in malloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:75
      #1 0x55ed3602346e in map__get util/map.h:189
      #2 0x55ed36024cc4 in hist_entry__init util/hist.c:476
      #3 0x55ed36025208 in hist_entry__new util/hist.c:588
      #4 0x55ed36027c05 in hierarchy_insert_entry util/hist.c:1587
      #5 0x55ed36027e2e in hists__hierarchy_insert_entry util/hist.c:1638
      #6 0x55ed36027fa4 in hists__collapse_insert_entry util/hist.c:1685
      #7 0x55ed360283e8 in hists__collapse_resort util/hist.c:1776
      #8 0x55ed35de0323 in report__collapse_hists /home/namhyung/project/linux/tools/perf/builtin-report.c:735
      #9 0x55ed35de15b4 in __cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1119
      #10 0x55ed35de43dc in cmd_report /home/namhyung/project/linux/tools/perf/builtin-report.c:1867
      #11 0x55ed35e66767 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:351
      #12 0x55ed35e66a0e in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:404
      #13 0x55ed35e66b67 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:448
      #14 0x55ed35e66eb0 in main /home/namhyung/project/linux/tools/perf/perf.c:556
      #15 0x7f340ac33d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
  ...

  $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak'
  93

I found that hist_entry__delete() missed to release child entries in the
hierarchy tree (hroot_{in,out}).  It needs to iterate the child entries
and call hist_entry__delete() recursively.

After this change:

  $ perf report -H --stdio 2>&1 | grep -c '^Indirect leak'
  0

Reported-by: Ian Rogers <irogers@google.com>
Tested-by Thomas Falcon <thomas.falcon@intel.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250307061250.320849-2-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Mar 31, 2025
The env.pmu_mapping can be leaked when it reads data from a pipe on AMD.
For a pipe data, it reads the header data including pmu_mapping from
PERF_RECORD_HEADER_FEATURE runtime.  But it's already set in:

  perf_session__new()
    __perf_session__new()
      evlist__init_trace_event_sample_raw()
        evlist__has_amd_ibs()
          perf_env__nr_pmu_mappings()

Then it'll overwrite that when it processes the HEADER_FEATURE record.
Here's a report from address sanitizer.

  Direct leak of 2689 byte(s) in 1 object(s) allocated from:
    #0 0x7fed8f814596 in realloc ../../../../src/libsanitizer/lsan/lsan_interceptors.cpp:98
    #1 0x5595a7d416b1 in strbuf_grow util/strbuf.c:64
    #2 0x5595a7d414ef in strbuf_init util/strbuf.c:25
    #3 0x5595a7d0f4b7 in perf_env__read_pmu_mappings util/env.c:362
    #4 0x5595a7d12ab7 in perf_env__nr_pmu_mappings util/env.c:517
    #5 0x5595a7d89d2f in evlist__has_amd_ibs util/amd-sample-raw.c:315
    #6 0x5595a7d87fb2 in evlist__init_trace_event_sample_raw util/sample-raw.c:23
    #7 0x5595a7d7f893 in __perf_session__new util/session.c:179
    #8 0x5595a7b79572 in perf_session__new util/session.h:115
    #9 0x5595a7b7e9dc in cmd_report builtin-report.c:1603
    #10 0x5595a7c019eb in run_builtin perf.c:351
    #11 0x5595a7c01c92 in handle_internal_command perf.c:404
    #12 0x5595a7c01deb in run_argv perf.c:448
    #13 0x5595a7c02134 in main perf.c:556
    #14 0x7fed85833d67 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

Let's free the existing pmu_mapping data if any.

Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250311000416.817631-1-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Apr 1, 2025
Currently, when no active threads are running, a root user using nfsdctl
command can try to remove a particular listener from the list of previously
added ones, then start the server by increasing the number of threads,
it leads to the following problem:

[  158.835354] refcount_t: addition on 0; use-after-free.
[  158.835603] WARNING: CPU: 2 PID: 9145 at lib/refcount.c:25 refcount_warn_saturate+0x160/0x1a0
[  158.836017] Modules linked in: rpcrdma rdma_cm iw_cm ib_cm ib_core nfsd auth_rpcgss nfs_acl lockd grace overlay isofs uinput snd_seq_dummy snd_hrtimer nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 rfkill ip_set nf_tables qrtr sunrpc vfat fat uvcvideo videobuf2_vmalloc videobuf2_memops uvc videobuf2_v4l2 videodev videobuf2_common snd_hda_codec_generic mc e1000e snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore sg loop dm_multipath dm_mod nfnetlink vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vmw_vmci vsock xfs libcrc32c crct10dif_ce ghash_ce vmwgfx sha2_ce sha256_arm64 sr_mod sha1_ce cdrom nvme drm_client_lib drm_ttm_helper ttm nvme_core drm_kms_helper nvme_auth drm fuse
[  158.840093] CPU: 2 UID: 0 PID: 9145 Comm: nfsd Kdump: loaded Tainted: G    B   W          6.13.0-rc6+ #7
[  158.840624] Tainted: [B]=BAD_PAGE, [W]=WARN
[  158.840802] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.24006586.BA64.2406042154 06/04/2024
[  158.841220] pstate: 6140000 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[  158.841563] pc : refcount_warn_saturate+0x160/0x1a0
[  158.841780] lr : refcount_warn_saturate+0x160/0x1a0
[  158.842000] sp : ffff800089be7d80
[  158.842147] x29: ffff800089be7d80 x28: ffff00008e68c148 x27: ffff00008e68c148
[  158.842492] x26: ffff0002e3b5c000 x25: ffff600011cd1829 x24: ffff00008653c010
[  158.842832] x23: ffff00008653c000 x22: 1fffe00011cd1829 x21: ffff00008653c028
[  158.843175] x20: 0000000000000002 x19: ffff00008653c010 x18: 0000000000000000
[  158.843505] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[  158.843836] x14: 0000000000000000 x13: 0000000000000001 x12: ffff600050a26493
[  158.844143] x11: 1fffe00050a26492 x10: ffff600050a26492 x9 : dfff800000000000
[  158.844475] x8 : 00009fffaf5d9b6e x7 : ffff000285132493 x6 : 0000000000000001
[  158.844823] x5 : ffff000285132490 x4 : ffff600050a26493 x3 : ffff8000805e72bc
[  158.845174] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000098588000
[  158.845528] Call trace:
[  158.845658]  refcount_warn_saturate+0x160/0x1a0 (P)
[  158.845894]  svc_recv+0x58c/0x680 [sunrpc]
[  158.846183]  nfsd+0x1fc/0x348 [nfsd]
[  158.846390]  kthread+0x274/0x2f8
[  158.846546]  ret_from_fork+0x10/0x20
[  158.846714] ---[ end trace 0000000000000000 ]---

nfsd_nl_listener_set_doit() would manipulate the list of transports of
server's sv_permsocks and close the specified listener but the other
list of transports (server's sp_xprts list) would not be changed leading
to the problem above.

Instead, determined if the nfsdctl is trying to remove a listener, in
which case, delete all the existing listener transports and re-create
all-but-the-removed ones.

Fixes: 16a4711 ("NFSD: add listener-{set,get} netlink command")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
pull bot pushed a commit that referenced this pull request Apr 1, 2025
…ge_order()

Patch series "mm: MM owner tracking for large folios (!hugetlb) +
CONFIG_NO_PAGE_MAPCOUNT", v3.

Let's add an "easy" way to decide -- without false positives, without
page-mapcounts and without page table/rmap scanning -- whether a large
folio is "certainly mapped exclusively" into a single MM, or whether it
"maybe mapped shared" into multiple MMs.

Use that information to implement Copy-on-Write reuse, to convert
folio_likely_mapped_shared() to folio_maybe_mapped_share(), and to
introduce a kernel config option that lets us not use+maintain per-page
mapcounts in large folios anymore.

The bigger picture was presented at LSF/MM [1].

This series is effectively a follow-up on my early work [2], which
implemented a more precise, but also more complicated, way to identify
whether a large folio is "mapped shared" into multiple MMs or "mapped
exclusively" into a single MM.


1 Patch Organization
====================

Patch #1 -> #6: make more room in order-1 folios, so we have two
                "unsigned long" available for our purposes

Patch #7 -> #11: preparations

Patch #12: MM owner tracking for large folios

Patch #13: COW reuse for PTE-mapped anon THP

Patch #14: folio_maybe_mapped_shared()

Patch #15 -> #20: introduce and implement CONFIG_NO_PAGE_MAPCOUNT


2 MM owner tracking
===================

We assign each MM a unique ID ("MM ID"), to be able to squeeze more
information in our folios.  On 32bit we use 15-bit IDs, on 64bit we use
31-bit IDs.

For each large folios, we now store two MM-ID+mapcount ("slot")
combinations:
* mm0_id + mm0_mapcount
* mm1_id + mm1_mapcount

On 32bit, we use a 16-bit per-MM mapcount, on 64bit an ordinary 32bit
mapcount.  This way, we require 2x "unsigned long" on 32bit and 64bit for
both slots.

Paired with the large mapcount, we can reliably identify whether one of
these MMs is the current owner (-> owns all mappings) or even holds all
folio references (-> owns all mappings, and all references are from
mappings).

As long as only two MMs map folio pages at a time, we can reliably and
precisely identify whether a large folio is "mapped shared" or "mapped
exclusively".

Any additional MM that starts mapping the folio while there are no free
slots becomes an "untracked MM".  If one such "untracked MM" is the last
one mapping a folio exclusively, we will not detect the folio as "mapped
exclusively" but instead as "maybe mapped shared".  (exception: only a
single mapping remains)

So that's where the approach gets imprecise.

For now, we use a bit-spinlock to sync the large mapcount + slots, and
make sure we do keep the machinery fast, to not degrade (un)map
performance drastically: for example, we make sure to only use a single
atomic (when grabbing the bit-spinlock), like we would already perform
when updating the large mapcount.


3 CONFIG_NO_PAGE_MAPCOUNT
=========================

patch #15 -> #20 spell out and document what exactly is affected when not
maintaining the per-page mapcounts in large folios anymore.

Most importantly, as we cannot maintain folio->_nr_pages_mapped anymore
when (un)mapping pages, we'll account a complete folio as mapped if a
single page is mapped.  In addition, we'll not detect partially mapped
anonymous folios as such in all cases yet.

Likely less relevant changes include that we might now under-estimate the
USS (Unique Set Size) of a process, but never over-estimate it.

The goal is to make CONFIG_NO_PAGE_MAPCOUNT the default at some point, to
then slowly make it the only option, as we learn about real-life impacts
and possible ways to mitigate them.


4 Performance
=============

Detailed performance numbers were included in v1 [3], and not that much
changed between v1 and v2.

I did plenty of measurements on different systems in the meantime, that
all revealed slightly different results.

The pte-mapped-folio micro-benchmarks [4] are fairly sensitive to code
layout changes on some systems.  Especially the fork() benchmark started
being more-shaky-than-before on recent kernels for some reason.

In summary, with my micro-benchmarks:

* Small folios are not impacted.

* CoW performance seems to be mostly unchanged across all folios sizes.

* CoW reuse performance of large folios now matches CoW reuse
  performance of small folios, because we now actually implement the CoW
  reuse optimization.  On an Intel Xeon Silver 4210R I measured a ~65%
  reduction in runtime, on an arm64 system I measured ~54% reduction.

* munmap() performance improves with CONFIG_NO_PAGE_MAPCOUNT.  I saw
  double-digit % reduction (up to ~30% on an Intel Xeon Silver 4210R and
  up to ~70% on an AmpereOne A192-32X) with larger folios.  The larger the
  folios, the larger the performance improvement.

* munmao() performance very slightly (couple percent) degrades without
  CONFIG_NO_PAGE_MAPCOUNT for smaller folios.  For larger folios, there
  seems to be no change at all.

* fork() performance improves with CONFIG_NO_PAGE_MAPCOUNT.  I saw
  double-digit % reduction (up to ~20% on an Intel Xeon Silver 4210R and
  up to ~10% on an AmpereOne A192-32X) with larger folios.  The larger the
  folios, the larger the performance improvement.

* While fork() performance without CONFIG_NO_PAGE_MAPCOUNT seems to be
  almost unchanged on some systems, I saw some degradation for smaller
  folios on the AmpereOne A192-32X.  I did not investigate the details
  yet, but I suspect code layout changes or suboptimal code placement /
  inlining.

I'm not to worried about the fork() micro-benchmarks for smaller folios
given how shaky the results are lately and by how much we improved fork()
performance recently.

I also ran case-anon-cow-rand and case-anon-cow-seq part of
vm-scalability, to assess the scalability and the impact of the
bit-spinlock.  My measurements on a two 2-socket 10-core Intel Xeon Silver
4210R CPU revealed no significant changes.

Similarly, running these benchmarks with 2 MiB THPs enabled on the
AmpereOne A192-32X with 192 cores, I got < 1% difference with < 1% stdev,
which is nice.

So far, I did not get my hands on a similarly large system with multiple
sockets.

I found no other fitting scalability benchmarks that seem to really hammer
on concurrent mapping/unmapping of large folio pages like
case-anon-cow-seq does.


5 Concerns
==========

5.1 Bit spinlock
----------------

I'm not quite happy about the bit-spinlock, but so far it does not seem to
affect scalability in my measurements.

If it ever becomes a problem we could either investigate improving the
locking, or simply stopping the MM tracking once there are "too many
mappings" and simply assume that the folio is "mapped shared" until it was
freed.

This would be similar (but slightly different) to the "0,1,2,stopped"
counting idea Willy had at some point.  Adding that logic to "stop
tracking" adds more code to the hot path, so I avoided that for now.


5.2 folio_maybe_mapped_shared()
-------------------------------

I documented the change from folio_likely_mapped_shared() to
folio_maybe_mapped_shared() quite extensively.  If we run into surprises,
I have some ideas on how to resolve them.  For now, I think we should be
fine.


5.3 Added code to map/unmap hot path
------------------------------------

So far, it looks like the added code on the rmap hot path does not really
seem to matter much in the bigger picture.  I'd like to further reduce it
(and possibly improve fork() performance further), but I don't easily see
how right now.  Well, and I am out of puff 🙂

Having that said, alternatives I considered (e.g., per-MM per-folio
mapcount) would add a lot more overhead to these hot paths.


6 Future Work
=============

6.1 Large mapcount
------------------

It would be very handy if the large mapcount would count how often folio
pages are actually mapped into page tables: a PMD on x86-64 would count
512 times.  Calculating the average per-page mapcount will be easy, and
remapping (PMD->PTE) folios would get even faster.

That would also remove the need for the entire mapcount (except for
PMD-sized folios for memory statistics reasons ...), and allow for mapping
folios larger than PMDs (e.g., 4 MiB) easily.

We likely would also have to take the same number of folio references to
make our folio_mapcount() == folio_ref_count() work, and we'd want to be
able to avoid mapcount+refcount overflows: this could already become an
issue with pte-mapped PUD-sized folios (fsdax).

One approach we discussed in the THP cabal meeting is (1) extending the
mapcount for large folios to 64bit (at least on 64bit systems) and (2)
keeping the refcount at 32bit, but (3) having exactly one reference if the
the mapcount != 0.

It should be doable, but there are some corner cases to consider on the
unmap path; it is something that I will be looking into next.


6.2 hugetlb
-----------

I'd love to make use of the same tracking also for hugetlb.

The real problem is PMD table sharing: getting a page mapped by MM X and
unmapped by MM Y will not work.  With mshare, that problem should not
exist (all mapping/unmapping will be routed through the mshare MM).

[1] https://lwn.net/Articles/974223/
[2] https://lore.kernel.org/linux-mm/a9922f58-8129-4f15-b160-e0ace581bcbe@redhat.com/T/
[3] https://lkml.kernel.org/r/20240829165627.2256514-1-david@redhat.com
[4] https://gitlab.com/davidhildenbrand/scratchspace/-/raw/main/pte-mapped-folio-benchmarks.c


This patch (of 20):

Let's factor it out into a simple helper function.  This helper will also
come in handy when working with code where we know that our folio is
large.

Maybe in the future we'll have the order readily available for small and
large folios; in that case, folio_large_order() would simply translate to
folio_order().

Link: https://lkml.kernel.org/r/20250303163014.1128035-1-david@redhat.com
Link: https://lkml.kernel.org/r/20250303163014.1128035-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lance Yang <ioworker0@gmail.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirks^H^Hski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: Michal Koutn <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: tejun heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pull bot pushed a commit that referenced this pull request Apr 3, 2025
When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().

An example from v5.4, similar problem also exists in upstream:

    crash> bt 2091206
    PID: 2091206  TASK: ffff2050df92a300  CPU: 109  COMMAND: "kworker/u260:0"
     #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
     #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
     #2 [ffff800084a2f880] schedule at ffff800040bfa4b4
     #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
     #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
     #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
     #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
     #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
     #8 [ffff800084a2fa60] generic_make_request at ffff800040570138
     #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
    #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
    #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
    #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
    #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
    #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
    #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
    #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
    #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
    #18 [ffff800084a2fe70] kthread at ffff800040118de4

After commit 2def284 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.

Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().

Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Reviewed-by: Tianxiang Peng <txpeng@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
pull bot pushed a commit that referenced this pull request May 9, 2025
Without CONFIG_DRM_XE_GPUSVM set, GPU SVM is not initialized thus below
warning pops. Refine the flush work code to be controlled by the config
to avoid below warning:
"
[  453.132028] ------------[ cut here ]------------
[  453.132527] WARNING: CPU: 9 PID: 4491 at kernel/workqueue.c:4205 __flush_work+0x379/0x3a0
[  453.133355] Modules linked in: xe drm_ttm_helper ttm gpu_sched drm_buddy drm_suballoc_helper drm_gpuvm drm_exec
[  453.134352] CPU: 9 UID: 0 PID: 4491 Comm: xe_exec_mix_mod Tainted: G     U  W           6.15.0-rc3+ #7 PREEMPT(full)
[  453.135405] Tainted: [U]=USER, [W]=WARN
...
[  453.136921] RIP: 0010:__flush_work+0x379/0x3a0
[  453.137417] Code: 8b 45 00 48 8b 55 08 89 c7 48 c1 e8 04 83 e7 08 83 e0 0f 83 cf 02 89 c6 48 0f ba 6d 00 03 e9 d5 fe ff ff 0f 0b e9 db fd ff ff <0f> 0b 45 31 e4 e9 d1 fd ff ff 0f 0b e9 03 ff ff ff 0f 0b e9 d6 fe
[  453.139250] RSP: 0018:ffffc90000c67b18 EFLAGS: 00010246
[  453.139782] RAX: 0000000000000000 RBX: ffff888108a24000 RCX: 0000000000002000
[  453.140521] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8881016d61c8
[  453.141253] RBP: ffff8881016d61c8 R08: 0000000000000000 R09: 0000000000000000
[  453.141985] R10: 0000000000000000 R11: 0000000008a24000 R12: 0000000000000001
[  453.142709] R13: 0000000000000002 R14: 0000000000000000 R15: ffff888107db8c00
[  453.143450] FS:  00007f44853d4c80(0000) GS:ffff8882f469b000(0000) knlGS:0000000000000000
[  453.144276] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  453.144853] CR2: 00007f4487629228 CR3: 00000001016aa000 CR4: 00000000000406f0
[  453.145594] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  453.146320] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  453.147061] Call Trace:
[  453.147336]  <TASK>
[  453.147579]  ? tick_nohz_tick_stopped+0xd/0x30
[  453.148067]  ? xas_load+0x9/0xb0
[  453.148435]  ? xa_load+0x6f/0xb0
[  453.148781]  __xe_vm_bind_ioctl+0xbd5/0x1500 [xe]
[  453.149338]  ? dev_printk_emit+0x48/0x70
[  453.149762]  ? _dev_printk+0x57/0x80
[  453.150148]  ? drm_ioctl+0x17c/0x440
[  453.150544]  ? __drm_dev_vprintk+0x36/0x90
[  453.150983]  ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe]
[  453.151575]  ? drm_ioctl_kernel+0x9f/0xf0
[  453.151998]  ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe]
[  453.152560]  drm_ioctl_kernel+0x9f/0xf0
[  453.152968]  drm_ioctl+0x20f/0x440
[  453.153332]  ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe]
[  453.153893]  ? ioctl_has_perm.constprop.0.isra.0+0xae/0x100
[  453.154489]  ? memory_bm_test_bit+0x5/0x60
[  453.154935]  xe_drm_ioctl+0x47/0x70 [xe]
[  453.155419]  __x64_sys_ioctl+0x8d/0xc0
[  453.155824]  do_syscall_64+0x47/0x110
[  453.156228]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
"

v2 (Matt):
    refine commit message to have more details
    add Fixes tag
    move the code to xe_svm.h which already have the config
    remove a blank line per codestyle suggestion

Fixes: 63f6e48 ("drm/xe: Add SVM garbage collector")
Cc: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://lore.kernel.org/r/20250502170052.1787973-1-shuicheng.lin@intel.com
(cherry picked from commit 9d80698)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
pull bot pushed a commit that referenced this pull request May 26, 2025
When calling the diag for DCSS unload on a non-IPL CPU, the sclp maximum
memory detection on the next IPL would falsely return the end of the
previously loaded DCSS.

This is because of an issue in z/VM, so work around it by always calling
the diag for DCSS unload on IPL CPU 0. That CPU cannot be set offline,
so the dcss_diag() call can directly be scheduled to CPU 0.

The wrong maximum memory value returned by sclp would only affect KASAN
kernels. When a DCSS within the falsely reported extra memory range is
loaded and accessed again, it would result in a kernel crash:

Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 001c0000a3ffe000 TEID: 001c0000a3ffe803
Fault in home space mode while using kernel ASCE.
AS:000000039955400b R2:00000003fe3b400b R3:000000037a2a8007 S:0000000000000020
Oops: 0010 ilc:3 [#1]SMP
[...]
CPU: 2 UID: 0 PID: 1563 Comm: mount Kdump: loaded Not tainted 6.15.0-rc5-11546-g3ea93fb3d026-dirty #7 NONE
Hardware name: IBM 3931 A01 704 (z/VM 7.4.0)
Krnl PSW : 0704c00180000000 000da6f2b338faf2 (kasan_check_range+0x172/0x310)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000040 001c0000a3ffe000 000000051fff0000 0000000000001000
           0000000000000000 000da6f233380ff6 00000000000001f8 0000000000000000
           001c0000a3ffe200 0000000000000040 001c0000a3ffe200 0000000000000200
           000003ff97a2cfa8 0000000000000000 0000000000000010 000da672b58af070
Krnl Code: 000da6f2b338fae2: 41101008            la      %r1,8(%r1)
           000da6f2b338fae6: eca100268064       cgrj    %r10,%r1,8,000da6f2b338fb32
          #000da6f2b338faec: ebe00002000c       srlg    %r14,%r0,2
          >000da6f2b338faf2: e3b010000002       ltg     %r11,0(%r1)
           000da6f2b338faf8: a77400a8           brc     7,000da6f2b338fc48
           000da6f2b338fafc: 41b01008           la      %r11,8(%r1)
           000da6f2b338fb00: b904001b           lgr     %r1,%r11
           000da6f2b338fb04: e3a0b0000002       ltg     %r10,0(%r11)
Call Trace:
 [<000da6f2b338faf2>] kasan_check_range+0x172/0x310
 [<000da6f2b3390b3c>] __asan_memcpy+0x3c/0x90
 [<000da6f233380ff6>] dcssblk_submit_bio+0x3a6/0x620 [dcssblk]
 [<000da6f2b3eb403c>] __submit_bio+0x25c/0x4a0
 [<000da6f2b3eb43bc>] __submit_bio_noacct+0x13c/0x450
 [<000da6f2b3eb4bde>] submit_bio_noacct_nocheck+0x50e/0x620
 [<000da6f2b34f4978>] mpage_readahead+0x318/0x3f0
 [<000da6f2b31edbe6>] read_pages+0x156/0x740
 [<000da6f2b31ee594>] page_cache_ra_unbounded+0x3c4/0x610
 [<000da6f2b31ef094>] force_page_cache_ra+0x1f4/0x2d0
 [<000da6f2b31d092e>] filemap_get_pages+0x2ce/0xaa0
 [<000da6f2b31d1428>] filemap_read+0x328/0x9a0
 [<000da6f2b3e9b7e8>] blkdev_read_iter+0x228/0x3b0
 [<000da6f2b340f7a6>] vfs_read+0x5b6/0x7f0
 [<000da6f2b34110be>] ksys_read+0x10e/0x1e0
 [<000da6f2b4e7acb2>] __do_syscall+0x122/0x1f0
 [<000da6f2b4e93ffe>] system_call+0x6e/0x90
Last Breaking-Event-Address:
 [<000da6f2b338faac>] kasan_check_range+0x12c/0x310
Kernel panic - not syncing: Fatal exception: panic_on_oops

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
pull bot pushed a commit that referenced this pull request May 28, 2025
ACPICA commit 1c28da2242783579d59767617121035dafba18c3

This was originally done in NetBSD:
NetBSD/src@b69d1ac
and is the correct alternative to the smattering of `memcpy`s I
previously contributed to this repository.

This also sidesteps the newly strict checks added in UBSAN:
llvm/llvm-project@7926744

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #1.2  0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c
  #1.1  0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c
  #1    0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c
  #2    0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f
  #3    0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723
  #4    0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e
  #5    0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089
  #6    0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169
  #7    0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a
  #8    0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7
  #9    0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979
  #10   0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f
  #11   0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf
  #12   0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278
  #13   0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87
  #14   0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d
  #15   0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e
  #16   0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad
  #17   0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e
  #18   0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7
  #19   0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342
  #20   0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3
  #21   0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616
  #22   0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323
  #23   0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76
  #24   0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831
  #25   0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc
  #26   0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58
  #27   0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159
  #28   0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414
  #29   0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d
  #30   0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7
  #31   0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66
  #32   0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9
  #33   0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d
  #34   0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983
  #35   0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e
  #36   0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509
  #37   0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958
  #38   0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247
  #39   0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962
  #40   0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30
  #41   0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d

Link: acpica/acpica@1c28da22
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/4664267.LvFx2qVVIh@rjwysocki.net
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
[ rjw: Pick up the tag from Tamir ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
pull bot pushed a commit that referenced this pull request Jul 17, 2025
A crash in conntrack was reported while trying to unlink the conntrack
entry from the hash bucket list:
    [exception RIP: __nf_ct_delete_from_lists+172]
    [..]
 #7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack]
 #8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack]
 #9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack]
    [..]

The nf_conn struct is marked as allocated from slab but appears to be in
a partially initialised state:

 ct hlist pointer is garbage; looks like the ct hash value
 (hence crash).
 ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected
 ct->timeout is 30000 (=30s), which is unexpected.

Everything else looks like normal udp conntrack entry.  If we ignore
ct->status and pretend its 0, the entry matches those that are newly
allocated but not yet inserted into the hash:
  - ct hlist pointers are overloaded and store/cache the raw tuple hash
  - ct->timeout matches the relative time expected for a new udp flow
    rather than the absolute 'jiffies' value.

If it were not for the presence of IPS_CONFIRMED,
__nf_conntrack_find_get() would have skipped the entry.

Theory is that we did hit following race:

cpu x 			cpu y			cpu z
 found entry E		found entry E
 E is expired		<preemption>
 nf_ct_delete()
 return E to rcu slab
					init_conntrack
					E is re-inited,
					ct->status set to 0
					reply tuplehash hnnode.pprev
					stores hash value.

cpu y found E right before it was deleted on cpu x.
E is now re-inited on cpu z.  cpu y was preempted before
checking for expiry and/or confirm bit.

					->refcnt set to 1
					E now owned by skb
					->timeout set to 30000

If cpu y were to resume now, it would observe E as
expired but would skip E due to missing CONFIRMED bit.

					nf_conntrack_confirm gets called
					sets: ct->status |= CONFIRMED
					This is wrong: E is not yet added
					to hashtable.

cpu y resumes, it observes E as expired but CONFIRMED:
			<resumes>
			nf_ct_expired()
			 -> yes (ct->timeout is 30s)
			confirmed bit set.

cpu y will try to delete E from the hashtable:
			nf_ct_delete() -> set DYING bit
			__nf_ct_delete_from_lists

Even this scenario doesn't guarantee a crash:
cpu z still holds the table bucket lock(s) so y blocks:

			wait for spinlock held by z

					CONFIRMED is set but there is no
					guarantee ct will be added to hash:
					"chaintoolong" or "clash resolution"
					logic both skip the insert step.
					reply hnnode.pprev still stores the
					hash value.

					unlocks spinlock
					return NF_DROP
			<unblocks, then
			 crashes on hlist_nulls_del_rcu pprev>

In case CPU z does insert the entry into the hashtable, cpu y will unlink
E again right away but no crash occurs.

Without 'cpu y' race, 'garbage' hlist is of no consequence:
ct refcnt remains at 1, eventually skb will be free'd and E gets
destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy.

To resolve this, move the IPS_CONFIRMED assignment after the table
insertion but before the unlock.

Pablo points out that the confirm-bit-store could be reordered to happen
before hlist add resp. the timeout fixup, so switch to set_bit and
before_atomic memory barrier to prevent this.

It doesn't matter if other CPUs can observe a newly inserted entry right
before the CONFIRMED bit was set:

Such event cannot be distinguished from above "E is the old incarnation"
case: the entry will be skipped.

Also change nf_ct_should_gc() to first check the confirmed bit.

The gc sequence is:
 1. Check if entry has expired, if not skip to next entry
 2. Obtain a reference to the expired entry.
 3. Call nf_ct_should_gc() to double-check step 1.

nf_ct_should_gc() is thus called only for entries that already failed an
expiry check. After this patch, once the confirmed bit check passes
ct->timeout has been altered to reflect the absolute 'best before' date
instead of a relative time.  Step 3 will therefore not remove the entry.

Without this change to nf_ct_should_gc() we could still get this sequence:

 1. Check if entry has expired.
 2. Obtain a reference.
 3. Call nf_ct_should_gc() to double-check step 1:
    4 - entry is still observed as expired
    5 - meanwhile, ct->timeout is corrected to absolute value on other CPU
      and confirm bit gets set
    6 - confirm bit is seen
    7 - valid entry is removed again

First do check 6), then 4) so the gc expiry check always picks up either
confirmed bit unset (entry gets skipped) or expiry re-check failure for
re-inited conntrack objects.

This change cannot be backported to releases before 5.19. Without
commit 8a75a2c ("netfilter: conntrack: remove unconfirmed list")
|= IPS_CONFIRMED line cannot be moved without further changes.

Cc: Razvan Cojocaru <rzvncj@gmail.com>
Link: https://lore.kernel.org/netfilter-devel/20250627142758.25664-1-fw@strlen.de/
Link: https://lore.kernel.org/netfilter-devel/4239da15-83ff-4ca4-939d-faef283471bb@gmail.com/
Fixes: 1397af5 ("netfilter: conntrack: remove the percpu dying list")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
pull bot pushed a commit that referenced this pull request Jul 29, 2025
The hfsplus_bnode_read() method can trigger the issue:

[  174.852007][ T9784] ==================================================================
[  174.852709][ T9784] BUG: KASAN: slab-out-of-bounds in hfsplus_bnode_read+0x2f4/0x360
[  174.853412][ T9784] Read of size 8 at addr ffff88810b5fc6c0 by task repro/9784
[  174.854059][ T9784]
[  174.854272][ T9784] CPU: 1 UID: 0 PID: 9784 Comm: repro Not tainted 6.16.0-rc3 #7 PREEMPT(full)
[  174.854281][ T9784] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  174.854286][ T9784] Call Trace:
[  174.854289][ T9784]  <TASK>
[  174.854292][ T9784]  dump_stack_lvl+0x10e/0x1f0
[  174.854305][ T9784]  print_report+0xd0/0x660
[  174.854315][ T9784]  ? __virt_addr_valid+0x81/0x610
[  174.854323][ T9784]  ? __phys_addr+0xe8/0x180
[  174.854330][ T9784]  ? hfsplus_bnode_read+0x2f4/0x360
[  174.854337][ T9784]  kasan_report+0xc6/0x100
[  174.854346][ T9784]  ? hfsplus_bnode_read+0x2f4/0x360
[  174.854354][ T9784]  hfsplus_bnode_read+0x2f4/0x360
[  174.854362][ T9784]  hfsplus_bnode_dump+0x2ec/0x380
[  174.854370][ T9784]  ? __pfx_hfsplus_bnode_dump+0x10/0x10
[  174.854377][ T9784]  ? hfsplus_bnode_write_u16+0x83/0xb0
[  174.854385][ T9784]  ? srcu_gp_start+0xd0/0x310
[  174.854393][ T9784]  ? __mark_inode_dirty+0x29e/0xe40
[  174.854402][ T9784]  hfsplus_brec_remove+0x3d2/0x4e0
[  174.854411][ T9784]  __hfsplus_delete_attr+0x290/0x3a0
[  174.854419][ T9784]  ? __pfx_hfs_find_1st_rec_by_cnid+0x10/0x10
[  174.854427][ T9784]  ? __pfx___hfsplus_delete_attr+0x10/0x10
[  174.854436][ T9784]  ? __asan_memset+0x23/0x50
[  174.854450][ T9784]  hfsplus_delete_all_attrs+0x262/0x320
[  174.854459][ T9784]  ? __pfx_hfsplus_delete_all_attrs+0x10/0x10
[  174.854469][ T9784]  ? rcu_is_watching+0x12/0xc0
[  174.854476][ T9784]  ? __mark_inode_dirty+0x29e/0xe40
[  174.854483][ T9784]  hfsplus_delete_cat+0x845/0xde0
[  174.854493][ T9784]  ? __pfx_hfsplus_delete_cat+0x10/0x10
[  174.854507][ T9784]  hfsplus_unlink+0x1ca/0x7c0
[  174.854516][ T9784]  ? __pfx_hfsplus_unlink+0x10/0x10
[  174.854525][ T9784]  ? down_write+0x148/0x200
[  174.854532][ T9784]  ? __pfx_down_write+0x10/0x10
[  174.854540][ T9784]  vfs_unlink+0x2fe/0x9b0
[  174.854549][ T9784]  do_unlinkat+0x490/0x670
[  174.854557][ T9784]  ? __pfx_do_unlinkat+0x10/0x10
[  174.854565][ T9784]  ? __might_fault+0xbc/0x130
[  174.854576][ T9784]  ? getname_flags.part.0+0x1c5/0x550
[  174.854584][ T9784]  __x64_sys_unlink+0xc5/0x110
[  174.854592][ T9784]  do_syscall_64+0xc9/0x480
[  174.854600][ T9784]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  174.854608][ T9784] RIP: 0033:0x7f6fdf4c3167
[  174.854614][ T9784] Code: f0 ff ff 73 01 c3 48 8b 0d 26 0d 0e 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 08
[  174.854622][ T9784] RSP: 002b:00007ffcb948bca8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
[  174.854630][ T9784] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6fdf4c3167
[  174.854636][ T9784] RDX: 00007ffcb948bcc0 RSI: 00007ffcb948bcc0 RDI: 00007ffcb948bd50
[  174.854641][ T9784] RBP: 00007ffcb948cd90 R08: 0000000000000001 R09: 00007ffcb948bb40
[  174.854645][ T9784] R10: 00007f6fdf564fc0 R11: 0000000000000206 R12: 0000561e1bc9c2d0
[  174.854650][ T9784] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[  174.854658][ T9784]  </TASK>
[  174.854661][ T9784]
[  174.879281][ T9784] Allocated by task 9784:
[  174.879664][ T9784]  kasan_save_stack+0x20/0x40
[  174.880082][ T9784]  kasan_save_track+0x14/0x30
[  174.880500][ T9784]  __kasan_kmalloc+0xaa/0xb0
[  174.880908][ T9784]  __kmalloc_noprof+0x205/0x550
[  174.881337][ T9784]  __hfs_bnode_create+0x107/0x890
[  174.881779][ T9784]  hfsplus_bnode_find+0x2d0/0xd10
[  174.882222][ T9784]  hfsplus_brec_find+0x2b0/0x520
[  174.882659][ T9784]  hfsplus_delete_all_attrs+0x23b/0x320
[  174.883144][ T9784]  hfsplus_delete_cat+0x845/0xde0
[  174.883595][ T9784]  hfsplus_rmdir+0x106/0x1b0
[  174.884004][ T9784]  vfs_rmdir+0x206/0x690
[  174.884379][ T9784]  do_rmdir+0x2b7/0x390
[  174.884751][ T9784]  __x64_sys_rmdir+0xc5/0x110
[  174.885167][ T9784]  do_syscall_64+0xc9/0x480
[  174.885568][ T9784]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  174.886083][ T9784]
[  174.886293][ T9784] The buggy address belongs to the object at ffff88810b5fc600
[  174.886293][ T9784]  which belongs to the cache kmalloc-192 of size 192
[  174.887507][ T9784] The buggy address is located 40 bytes to the right of
[  174.887507][ T9784]  allocated 152-byte region [ffff88810b5fc600, ffff88810b5fc698)
[  174.888766][ T9784]
[  174.888976][ T9784] The buggy address belongs to the physical page:
[  174.889533][ T9784] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b5fc
[  174.890295][ T9784] flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
[  174.890927][ T9784] page_type: f5(slab)
[  174.891284][ T9784] raw: 057ff00000000000 ffff88801b4423c0 ffffea000426dc80 dead000000000002
[  174.892032][ T9784] raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
[  174.892774][ T9784] page dumped because: kasan: bad access detected
[  174.893327][ T9784] page_owner tracks the page as allocated
[  174.893825][ T9784] page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52c00(GFP_NOIO|__GFP_NOWARN|__GFP_NO1
[  174.895373][ T9784]  post_alloc_hook+0x1c0/0x230
[  174.895801][ T9784]  get_page_from_freelist+0xdeb/0x3b30
[  174.896284][ T9784]  __alloc_frozen_pages_noprof+0x25c/0x2460
[  174.896810][ T9784]  alloc_pages_mpol+0x1fb/0x550
[  174.897242][ T9784]  new_slab+0x23b/0x340
[  174.897614][ T9784]  ___slab_alloc+0xd81/0x1960
[  174.898028][ T9784]  __slab_alloc.isra.0+0x56/0xb0
[  174.898468][ T9784]  __kmalloc_noprof+0x2b0/0x550
[  174.898896][ T9784]  usb_alloc_urb+0x73/0xa0
[  174.899289][ T9784]  usb_control_msg+0x1cb/0x4a0
[  174.899718][ T9784]  usb_get_string+0xab/0x1a0
[  174.900133][ T9784]  usb_string_sub+0x107/0x3c0
[  174.900549][ T9784]  usb_string+0x307/0x670
[  174.900933][ T9784]  usb_cache_string+0x80/0x150
[  174.901355][ T9784]  usb_new_device+0x1d0/0x19d0
[  174.901786][ T9784]  register_root_hub+0x299/0x730
[  174.902231][ T9784] page last free pid 10 tgid 10 stack trace:
[  174.902757][ T9784]  __free_frozen_pages+0x80c/0x1250
[  174.903217][ T9784]  vfree.part.0+0x12b/0xab0
[  174.903645][ T9784]  delayed_vfree_work+0x93/0xd0
[  174.904073][ T9784]  process_one_work+0x9b5/0x1b80
[  174.904519][ T9784]  worker_thread+0x630/0xe60
[  174.904927][ T9784]  kthread+0x3a8/0x770
[  174.905291][ T9784]  ret_from_fork+0x517/0x6e0
[  174.905709][ T9784]  ret_from_fork_asm+0x1a/0x30
[  174.906128][ T9784]
[  174.906338][ T9784] Memory state around the buggy address:
[  174.906828][ T9784]  ffff88810b5fc580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[  174.907528][ T9784]  ffff88810b5fc600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  174.908222][ T9784] >ffff88810b5fc680: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc
[  174.908917][ T9784]                                            ^
[  174.909481][ T9784]  ffff88810b5fc700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  174.910432][ T9784]  ffff88810b5fc780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[  174.911401][ T9784] ==================================================================

The reason of the issue that code doesn't check the correctness
of the requested offset and length. As a result, incorrect value
of offset or/and length could result in access out of allocated
memory.

This patch introduces is_bnode_offset_valid() method that checks
the requested offset value. Also, it introduces
check_and_correct_requested_length() method that checks and
correct the requested length (if it is necessary). These methods
are used in hfsplus_bnode_read(), hfsplus_bnode_write(),
hfsplus_bnode_clear(), hfsplus_bnode_copy(), and hfsplus_bnode_move()
with the goal to prevent the access out of allocated memory
and triggering the crash.

Reported-by: Kun Hu <huk23@m.fudan.edu.cn>
Reported-by: Jiaji Qin <jjtan24@m.fudan.edu.cn>
Reported-by: Shuoran Bai <baishuoran@hrbeu.edu.cn>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Link: https://lore.kernel.org/r/20250703214804.244077-1-slava@dubeyko.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
pull bot pushed a commit that referenced this pull request Aug 2, 2025
pert script tests fails with segmentation fault as below:

  92: perf script tests:
  --- start ---
  test child forked, pid 103769
  DB test
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.012 MB /tmp/perf-test-script.7rbftEpOzX/perf.data (9 samples) ]
  /usr/libexec/perf-core/tests/shell/script.sh: line 35:
  103780 Segmentation fault      (core dumped)
  perf script -i "${perfdatafile}" -s "${db_test}"
  --- Cleaning up ---
  ---- end(-1) ----
  92: perf script tests                                               : FAILED!

Backtrace pointed to :
	#0  0x0000000010247dd0 in maps.machine ()
	#1  0x00000000101d178c in db_export.sample ()
	#2  0x00000000103412c8 in python_process_event ()
	#3  0x000000001004eb28 in process_sample_event ()
	#4  0x000000001024fcd0 in machines.deliver_event ()
	#5  0x000000001025005c in perf_session.deliver_event ()
	#6  0x00000000102568b0 in __ordered_events__flush.part.0 ()
	#7  0x0000000010251618 in perf_session.process_events ()
	#8  0x0000000010053620 in cmd_script ()
	#9  0x00000000100b5a28 in run_builtin ()
	#10 0x00000000100b5f94 in handle_internal_command ()
	#11 0x0000000010011114 in main ()

Further investigation reveals that this occurs in the `perf script tests`,
because it uses `db_test.py` script. This script sets `perf_db_export_mode = True`.

With `perf_db_export_mode` enabled, if a sample originates from a hypervisor,
perf doesn't set maps for "[H]" sample in the code. Consequently, `al->maps` remains NULL
when `maps__machine(al->maps)` is called from `db_export__sample`.

As al->maps can be NULL in case of Hypervisor samples , use thread->maps
because even for Hypervisor sample, machine should exist.
If we don't have machine for some reason, return -1 to avoid segmentation fault.

Reported-by: Disha Goel <disgoel@linux.ibm.com>
Signed-off-by: Aditya Bodkhe <aditya.b1@linux.ibm.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Disha Goel <disgoel@linux.ibm.com>
Link: https://lore.kernel.org/r/20250429065132.36839-1-adityab1@linux.ibm.com
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Aug 2, 2025
Without the change `perf `hangs up on charaster devices. On my system
it's enough to run system-wide sampler for a few seconds to get the
hangup:

    $ perf record -a -g --call-graph=dwarf
    $ perf report
    # hung

`strace` shows that hangup happens on reading on a character device
`/dev/dri/renderD128`

    $ strace -y -f -p 2780484
    strace: Process 2780484 attached
    pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached

It's call trace descends into `elfutils`:

    $ gdb -p 2780484
    (gdb) bt
    #0  0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0)
        at ../sysdeps/unix/sysv/linux/pread64.c:25
    #1  0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1
    #2  0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #3  0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #4  0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 ()
       from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #5  0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0)
        at util/dso.h:537
    #6  0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114
    #7  frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242
    #8  0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #9  0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1
    #12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0,
        thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127,
        best_effort=best_effort@entry=false) at util/thread.h:152
    #13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0,
        sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939
    #14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540,
        max_stack=127, symbols=true) at util/machine.c:2920
    #15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440,
        sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true)
        at util/machine.c:2970
    #16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440,
        sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198
    #17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0,
        evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127
    #18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127,
        arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255
    #19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540,
        evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334
    #20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0,
        file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367
    #21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245
    #22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324
    #23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224,
        file_path=0x105ffbf0 "perf.data") at util/session.c:1419
    #24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0,
    --Type <RET> for more, q to quit, c to continue without paging--
    quit
        prog=prog@entry=0x7fff9df81220) at util/session.c:2132
    #25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220)
        at util/session.c:2181
    #26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226
    #27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390
    #28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076
    #29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827
    #30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0)
        at perf.c:351
    #31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404
    #32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448
    #33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556

The hangup happens because nothing in` perf` or `elfutils` checks if a
mapped file is easily readable.

The change conservatively skips all non-regular files.

Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250505174419.2814857-1-slyich@gmail.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Aug 2, 2025
Symbolize stack traces by creating a live machine. Add this
functionality to dump_stack and switch dump_stack users to use
it. Switch TUI to use it. Add stack traces to the child test function
which can be useful to diagnose blocked code.

Example output:
```
$ perf test -vv PERF_RECORD_
...
  7: PERF_RECORD_* events & perf_sample fields:
  7: PERF_RECORD_* events & perf_sample fields                       : Running (1 active)
^C
Signal (2) while running tests.
Terminating tests with the same signal
Internal test harness failure. Completing any started tests:
:  7: PERF_RECORD_* events & perf_sample fields:

---- unexpected signal (2) ----
    #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
    #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
    #3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
    #4 0x7fc12fef1393 in __nanosleep nanosleep.c:26
    #5 0x7fc12ff02d68 in __sleep sleep.c:55
    #6 0x55788c63196b in test__PERF_RECORD perf-record.c:0
    #7 0x55788c620fb0 in run_test_child builtin-test.c:0
    #8 0x55788c5bd18d in start_command run-command.c:127
    #9 0x55788c621ef3 in __cmd_test builtin-test.c:0
    #10 0x55788c6225bf in cmd_test ??:0
    #11 0x55788c5afbd0 in run_builtin perf.c:0
    #12 0x55788c5afeeb in handle_internal_command perf.c:0
    #13 0x55788c52b383 in main ??:0
    #14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
    #15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    #16 0x55788c52b9d1 in _start ??:0

---- unexpected signal (2) ----
    #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
    #1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45
    #3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26
    #4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36
    #5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0
    #6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
    #7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
    #8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
    #9 0x7fc12fef1393 in __nanosleep nanosleep.c:26
    #10 0x7fc12ff02d68 in __sleep sleep.c:55
    #11 0x55788c63196b in test__PERF_RECORD perf-record.c:0
    #12 0x55788c620fb0 in run_test_child builtin-test.c:0
    #13 0x55788c5bd18d in start_command run-command.c:127
    #14 0x55788c621ef3 in __cmd_test builtin-test.c:0
    #15 0x55788c6225bf in cmd_test ??:0
    #16 0x55788c5afbd0 in run_builtin perf.c:0
    #17 0x55788c5afeeb in handle_internal_command perf.c:0
    #18 0x55788c52b383 in main ??:0
    #19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
    #20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
    #21 0x55788c52b9d1 in _start ??:0
  7: PERF_RECORD_* events & perf_sample fields                       : Skip (permissions)
```

Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250624210500.2121303-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Aug 2, 2025
Calling perf top with branch filters enabled on Intel CPU's
with branch counters logging (A.K.A LBR event logging [1]) support
results in a segfault.

$ perf top  -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter
...
Thread 27 "perf" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffafff76c0 (LWP 949003)]
perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
653			*width = env->cpu_pmu_caps ? env->br_cntr_width :
(gdb) bt
 #0  perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653
 #1  0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345
 #2  0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389
 #3  0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422
 #4  0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850
 #5  0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737
 #6  0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359
 #7  0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845
 #8  0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211
 #9  0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245
 #10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324
 #11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342
 #12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120
 #13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448
 #14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

The cause is that perf_env__find_br_cntr_info tries to access a
null pointer pmu_caps in the perf_env struct. A similar issue exists
for homogeneous core systems which use the cpu_pmu_caps structure.

Fix this by populating cpu_pmu_caps and pmu_caps structures with
values from sysfs when calling perf top with branch stack sampling
enabled.

[1], LBR event logging introduced here:
https://lore.kernel.org/all/20231025201626.3000228-5-kan.liang@linux.intel.com/

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20250612163659.1357950-2-thomas.falcon@intel.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
pull bot pushed a commit that referenced this pull request Aug 5, 2025
As syzbot [1] reported as below:

R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe17473450
R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520
 </TASK>
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
Read of size 8 at addr ffff88812d962278 by task syz-executor/564

CPU: 1 PID: 564 Comm: syz-executor Tainted: G        W          6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x158 lib/dump_stack.c:106
 print_address_description+0x71/0x210 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:427
 kasan_report+0x122/0x150 mm/kasan/report.c:531
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
 __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
 __list_del_entry include/linux/list.h:134 [inline]
 list_del_init include/linux/list.h:206 [inline]
 f2fs_inode_synced+0xf7/0x2e0 fs/f2fs/super.c:1531
 f2fs_update_inode+0x74/0x1c40 fs/f2fs/inode.c:585
 f2fs_update_inode_page+0x137/0x170 fs/f2fs/inode.c:703
 f2fs_write_inode+0x4ec/0x770 fs/f2fs/inode.c:731
 write_inode fs/fs-writeback.c:1460 [inline]
 __writeback_single_inode+0x4a0/0xab0 fs/fs-writeback.c:1677
 writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1733
 sync_inode_metadata+0xb6/0x110 fs/fs-writeback.c:2789
 f2fs_sync_inode_meta+0x16d/0x2a0 fs/f2fs/checkpoint.c:1159
 block_operations fs/f2fs/checkpoint.c:1269 [inline]
 f2fs_write_checkpoint+0xca3/0x2100 fs/f2fs/checkpoint.c:1658
 kill_f2fs_super+0x231/0x390 fs/f2fs/super.c:4668
 deactivate_locked_super+0x98/0x100 fs/super.c:332
 deactivate_super+0xaf/0xe0 fs/super.c:363
 cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1186
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1193
 task_work_run+0x1c6/0x230 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x9fb/0x2410 kernel/exit.c:871
 do_group_exit+0x210/0x2d0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030
 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f28b1b8e169
Code: Unable to access opcode bytes at 0x7f28b1b8e13f.
RSP: 002b:00007ffe174710a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f28b1c10879 RCX: 00007f28b1b8e169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000002 R08: 00007ffe1746ee47 R09: 00007ffe17472360
R10: 0000000000000009 R11: 0000000000000246 R12: 00007ffe17472360
R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520
 </TASK>

Allocated by task 569:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4f/0x2c0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x104/0x220 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 f2fs_alloc_inode+0x2d/0x340 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x186/0x880 fs/inode.c:1373
 f2fs_iget+0x55/0x4c60 fs/f2fs/inode.c:483
 f2fs_lookup+0x366/0xab0 fs/f2fs/namei.c:487
 __lookup_slow+0x2a3/0x3d0 fs/namei.c:1690
 lookup_slow+0x57/0x70 fs/namei.c:1707
 walk_component+0x2e6/0x410 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x180/0x490 fs/namei.c:2479
 filename_lookup+0x1f0/0x500 fs/namei.c:2508
 vfs_statx+0x10b/0x660 fs/stat.c:229
 vfs_fstatat fs/stat.c:267 [inline]
 vfs_lstat include/linux/fs.h:3424 [inline]
 __do_sys_newlstat fs/stat.c:423 [inline]
 __se_sys_newlstat+0xd5/0x350 fs/stat.c:417
 __x64_sys_newlstat+0x5b/0x70 fs/stat.c:417
 x64_sys_call+0x393/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:7
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 13:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:236
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1750
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x12d/0x2a0 mm/slub.c:3683
 f2fs_free_inode+0x24/0x30 fs/f2fs/super.c:1562
 i_callback+0x4c/0x70 fs/inode.c:250
 rcu_do_batch+0x503/0xb80 kernel/rcu/tree.c:2297
 rcu_core+0x5a2/0xe70 kernel/rcu/tree.c:2557
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
 handle_softirqs+0x178/0x500 kernel/softirq.c:578
 run_ksoftirqd+0x28/0x30 kernel/softirq.c:945
 smpboot_thread_fn+0x45a/0x8c0 kernel/smpboot.c:164
 kthread+0x270/0x310 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 call_rcu+0xd4/0xf70 kernel/rcu/tree.c:2845
 destroy_inode fs/inode.c:316 [inline]
 evict+0x7da/0x870 fs/inode.c:720
 iput_final fs/inode.c:1834 [inline]
 iput+0x62b/0x830 fs/inode.c:1860
 do_unlinkat+0x356/0x540 fs/namei.c:4397
 __do_sys_unlink fs/namei.c:4438 [inline]
 __se_sys_unlink fs/namei.c:4436 [inline]
 __x64_sys_unlink+0x49/0x50 fs/namei.c:4436
 x64_sys_call+0x958/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88812d961f20
 which belongs to the cache f2fs_inode_cache of size 1200
The buggy address is located 856 bytes inside of
 1200-byte region [ffff88812d961f20, ffff88812d9623d0)

The buggy address belongs to the physical page:
page:ffffea0004b65800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12d960
head:ffffea0004b65800 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff88810a94c500
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 569, tgid 568 (syz.2.16), ts 55943246141, free_ts 0
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1d0/0x1f0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x2e63/0x2ef0 mm/page_alloc.c:4328
 __alloc_pages+0x235/0x4b0 mm/page_alloc.c:5605
 alloc_slab_page include/linux/gfp.h:-1 [inline]
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0xec/0x4b0 mm/slub.c:1992
 ___slab_alloc+0x6f6/0xb50 mm/slub.c:3180
 __slab_alloc+0x5e/0xa0 mm/slub.c:3279
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x13f/0x220 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 f2fs_alloc_inode+0x2d/0x340 fs/f2fs/super.c:1419
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x186/0x880 fs/inode.c:1373
 f2fs_iget+0x55/0x4c60 fs/f2fs/inode.c:483
 f2fs_fill_super+0x3ad7/0x6bb0 fs/f2fs/super.c:4293
 mount_bdev+0x2ae/0x3e0 fs/super.c:1443
 f2fs_mount+0x34/0x40 fs/f2fs/super.c:4642
 legacy_get_tree+0xea/0x190 fs/fs_context.c:632
 vfs_get_tree+0x89/0x260 fs/super.c:1573
 do_new_mount+0x25a/0xa20 fs/namespace.c:3056
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88812d962100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812d962180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88812d962200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                                ^
 ffff88812d962280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812d962300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

[1] https://syzkaller.appspot.com/x/report.txt?x=13448368580000

This bug can be reproduced w/ the reproducer [2], once we enable
CONFIG_F2FS_CHECK_FS config, the reproducer will trigger panic as below,
so the direct reason of this bug is the same as the one below patch [3]
fixed.

kernel BUG at fs/f2fs/inode.c:857!
RIP: 0010:f2fs_evict_inode+0x1204/0x1a20
Call Trace:
 <TASK>
 evict+0x32a/0x7a0
 do_unlinkat+0x37b/0x5b0
 __x64_sys_unlink+0xad/0x100
 do_syscall_64+0x5a/0xb0
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8
RIP: 0010:f2fs_evict_inode+0x1204/0x1a20

[2] https://syzkaller.appspot.com/x/repro.c?x=17495ccc580000
[3] https://lore.kernel.org/linux-f2fs-devel/20250702120321.1080759-1-chao@kernel.org

Tracepoints before panic:

f2fs_unlink_enter: dev = (7,0), dir ino = 3, i_size = 4096, i_blocks = 8, name = file1
f2fs_unlink_exit: dev = (7,0), ino = 7, ret = 0
f2fs_evict_inode: dev = (7,0), ino = 7, pino = 3, i_mode = 0x81ed, i_size = 10, i_nlink = 0, i_blocks = 0, i_advise = 0x0
f2fs_truncate_node: dev = (7,0), ino = 7, nid = 8, block_address = 0x3c05

f2fs_unlink_enter: dev = (7,0), dir ino = 3, i_size = 4096, i_blocks = 8, name = file3
f2fs_unlink_exit: dev = (7,0), ino = 8, ret = 0
f2fs_evict_inode: dev = (7,0), ino = 8, pino = 3, i_mode = 0x81ed, i_size = 9000, i_nlink = 0, i_blocks = 24, i_advise = 0x4
f2fs_truncate: dev = (7,0), ino = 8, pino = 3, i_mode = 0x81ed, i_size = 0, i_nlink = 0, i_blocks = 24, i_advise = 0x4
f2fs_truncate_blocks_enter: dev = (7,0), ino = 8, i_size = 0, i_blocks = 24, start file offset = 0
f2fs_truncate_blocks_exit: dev = (7,0), ino = 8, ret = -2

The root cause is: in the fuzzed image, dnode #8 belongs to inode #7,
after inode #7 eviction, dnode #8 was dropped.

However there is dirent that has ino #8, so, once we unlink file3, in
f2fs_evict_inode(), both f2fs_truncate() and f2fs_update_inode_page()
will fail due to we can not load node #8, result in we missed to call
f2fs_inode_synced() to clear inode dirty status.

Let's fix this by calling f2fs_inode_synced() in error path of
f2fs_evict_inode().

PS: As I verified, the reproducer [2] can trigger this bug in v6.1.129,
but it failed in v6.16-rc4, this is because the testcase will stop due to
other corruption has been detected by f2fs:

F2FS-fs (loop0): inconsistent node block, node_type:2, nid:8, node_footer[nid:8,ino:8,ofs:0,cpver:5013063228981249506,blkaddr:15366]
F2FS-fs (loop0): f2fs_lookup: inode (ino=9) has zero i_nlink

Fixes: 0f18b46 ("f2fs: flush inode metadata when checkpoint is doing")
Closes: https://syzkaller.appspot.com/x/report.txt?x=13448368580000
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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