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@boryas boryas commented Oct 4, 2024

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boryas pushed a commit that referenced this pull request Oct 18, 2024
We can't take sb_lock while holding mark_lock, so split out
replicas_entry_validate() and replicas_entry_sb_validate() -
replicas_entry_validate() now uses the normal online device interface.

00039 ========= TEST   set_option
00039
00039 WATCHDOG 30
00040 bcachefs (vdb): starting version 1.12: rebalance_work_acct_fix opts=errors=panic
00040 bcachefs (vdb): initializing new filesystem
00040 bcachefs (vdb): going read-write
00040 bcachefs (vdb): marking superblocks
00040 bcachefs (vdb): initializing freespace
00040 bcachefs (vdb): done initializing freespace
00040 bcachefs (vdb): reading snapshots table
00040 bcachefs (vdb): reading snapshots done
00040 bcachefs (vdb): done starting filesystem
00040 zstd
00041 bcachefs (vdb): shutting down
00041 bcachefs (vdb): going read-only
00041 bcachefs (vdb): finished waiting for writes to stop
00041 bcachefs (vdb): flushing journal and stopping allocators, journal seq 3
00041 bcachefs (vdb): flushing journal and stopping allocators complete, journal seq 11
00041 bcachefs (vdb): shutdown complete, journal seq 12
00041 bcachefs (vdb): marking filesystem clean
00041 bcachefs (vdb): shutdown complete
00041 Setting option on offline fs
00041 bch2_write_super(): fatal error : attempting to write superblock that wasn't version downgraded (1.12: (unknown version) > 1.10: disk_accounting_v3)
00041 fatal error - emergency read only
00041 bch2_write_super(): fatal error : attempting to write superblock that wasn't version downgraded (1.12: (unknown version) > 1.10: disk_accounting_v3)
00042 bcachefs (vdb): starting version 1.12: rebalance_work_acct_fix opts=errors=panic,compression=zstd
00042 bcachefs (vdb): recovering from clean shutdown, journal seq 12
00042 bcachefs (vdb): accounting_read...
00042
00042 ======================================================
00042 WARNING: possible circular locking dependency detected
00042 6.12.0-rc1-ktest-g805e938a8502 #6807 Not tainted
00042 ------------------------------------------------------
00042 mount.bcachefs/665 is trying to acquire lock:
00045 ffffff80cc280908 (&c->sb_lock){+.+.}-{3:3}, at: bch2_replicas_entry_validate (fs/bcachefs/replicas.c:102)
00045
00045 but task is already holding lock:
00048 ffffff80cc284870 (&c->mark_lock){++++}-{0:0}, at: bch2_accounting_read (fs/bcachefs/disk_accounting.c:670 (discriminator 1))
00048
00048 which lock already depends on the new lock.
00048
00048
00048 the existing dependency chain (in reverse order) is:
00048
00048 -> #1 (&c->mark_lock){++++}-{0:0}:
00049 percpu_down_write (kernel/locking/percpu-rwsem.c:232)
00052 bch2_sb_replicas_to_cpu_replicas (fs/bcachefs/replicas.c:583)
00055 bch2_sb_to_fs (fs/bcachefs/super-io.c:614)
00057 bch2_fs_open (fs/bcachefs/super.c:828 fs/bcachefs/super.c:2050)
00060 bch2_fs_get_tree (fs/bcachefs/fs.c:2067)
00062 vfs_get_tree (fs/super.c:1801)
00064 path_mount (fs/namespace.c:3507 fs/namespace.c:3834)
00066 __arm64_sys_mount (fs/namespace.c:3847 fs/namespace.c:4055 fs/namespace.c:4032 fs/namespace.c:4032)
00067 invoke_syscall.constprop.0 (arch/arm64/include/asm/syscall.h:61 arch/arm64/kernel/syscall.c:54)
00068 do_el0_svc (include/linux/thread_info.h:127 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2) arch/arm64/kernel/syscall.c:151 (discriminator 2))
00069 el0_svc (arch/arm64/include/asm/irqflags.h:82 arch/arm64/include/asm/irqflags.h:123 arch/arm64/include/asm/irqflags.h:136 arch/arm64/kernel/entry-common.c:165 arch/arm64/kernel/entry-common.c:178 arch/arm64/kernel/entry-common.c:713)
00069 ========= FAILED TIMEOUT set_option in 30s

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
boryas pushed a commit that referenced this pull request Oct 18, 2024
This fixes an assertion pop in nocow_locking.c

00243 kernel BUG at fs/bcachefs/nocow_locking.c:41!
00243 Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
00243 Modules linked in:
00243 Hardware name: linux,dummy-virt (DT)
00243 pstate: 60001005 (nZCv daif -PAN -UAO -TCO -DIT +SSBS BTYPE=--)
00244 pc : bch2_bucket_nocow_unlock (/home/testdashboard/linux-7/fs/bcachefs/nocow_locking.c:41)
00244 lr : bkey_nocow_lock (/home/testdashboard/linux-7/fs/bcachefs/data_update.c:79)
00244 sp : ffffff80c82373b0
00244 x29: ffffff80c82373b0 x28: ffffff80e08958c0 x27: ffffff80e0880000
00244 x26: ffffff80c8237a98 x25: 00000000000000a0 x24: ffffff80c8237ab0
00244 x23: 00000000000000c0 x22: 0000000000000008 x21: 0000000000000000
00244 x20: ffffff80c8237a98 x19: 0000000000000018 x18: 0000000000000000
00244 x17: 0000000000000000 x16: 000000000000003f x15: 0000000000000000
00244 x14: 0000000000000008 x13: 0000000000000018 x12: 0000000000000000
00244 x11: 0000000000000000 x10: ffffff80e0880000 x9 : ffffffc0803ac1a4
00244 x8 : 0000000000000018 x7 : ffffff80c8237a88 x6 : ffffff80c8237ab0
00244 x5 : ffffff80e08988d0 x4 : 00000000ffffffff x3 : 0000000000000000
00244 x2 : 0000000000000004 x1 : 0003000000000d1e x0 : ffffff80e08988c0
00244 Call trace:
00244 bch2_bucket_nocow_unlock (/home/testdashboard/linux-7/fs/bcachefs/nocow_locking.c:41)
00245 bch2_data_update_init (/home/testdashboard/linux-7/fs/bcachefs/data_update.c:627 (discriminator 1))
00245 promote_alloc.isra.0 (/home/testdashboard/linux-7/fs/bcachefs/io_read.c:242 /home/testdashboard/linux-7/fs/bcachefs/io_read.c:304)
00245 __bch2_read_extent (/home/testdashboard/linux-7/fs/bcachefs/io_read.c:949)
00246 __bch2_read (/home/testdashboard/linux-7/fs/bcachefs/io_read.c:1215)
00246 bch2_direct_IO_read (/home/testdashboard/linux-7/fs/bcachefs/fs-io-direct.c:132)
00246 bch2_read_iter (/home/testdashboard/linux-7/fs/bcachefs/fs-io-direct.c:201)
00247 aio_read.constprop.0 (/home/testdashboard/linux-7/fs/aio.c:1602)
00247 io_submit_one.constprop.0 (/home/testdashboard/linux-7/fs/aio.c:2003 /home/testdashboard/linux-7/fs/aio.c:2052)
00248 __arm64_sys_io_submit (/home/testdashboard/linux-7/fs/aio.c:2111 /home/testdashboard/linux-7/fs/aio.c:2081 /home/testdashboard/linux-7/fs/aio.c:2081)
00248 invoke_syscall.constprop.0 (/home/testdashboard/linux-7/arch/arm64/include/asm/syscall.h:61 /home/testdashboard/linux-7/arch/arm64/kernel/syscall.c:54)
00248 ========= FAILED TIMEOUT tiering_variable_buckets_replicas in 1200s

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
boryas pushed a commit that referenced this pull request Oct 18, 2024
The purpose of btrfs_bbio_propagate_error() shall be propagating an error
of split bio to its original btrfs_bio, and tell the error to the upper
layer. However, it's not working well on some cases.

* Case 1. Immediate (or quick) end_bio with an error

When btrfs sends btrfs_bio to mirrored devices, btrfs calls
btrfs_bio_end_io() when all the mirroring bios are completed. If that
btrfs_bio was split, it is from btrfs_clone_bioset and its end_io function
is btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error()
accesses the orig_bbio's bio context to increase the error count.

That works well in most cases. However, if the end_io is called enough
fast, orig_bbio's (remaining part after split) bio context may not be
properly set at that time. Since the bio context is set when the orig_bbio
(the last btrfs_bio) is sent to devices, that might be too late for earlier
split btrfs_bio's completion.  That will result in NULL pointer
dereference.

That bug is easily reproducible by running btrfs/146 on zoned devices [1]
and it shows the following trace.

[1] You need raid-stripe-tree feature as it create "-d raid0 -m raid1" FS.

  BUG: kernel NULL pointer dereference, address: 0000000000000020
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ torvalds#474
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  Workqueue: writeback wb_workfn (flush-btrfs-5)
  RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs]
  BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0
  RSP: 0018:ffffc9000006f248 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc
  RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080
  RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001
  R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58
  R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158
  FS:  0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   ? __die_body.cold+0x19/0x26
   ? page_fault_oops+0x13e/0x2b0
   ? _printk+0x58/0x73
   ? do_user_addr_fault+0x5f/0x750
   ? exc_page_fault+0x76/0x240
   ? asm_exc_page_fault+0x22/0x30
   ? btrfs_bio_end_io+0xae/0xc0 [btrfs]
   ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs]
   btrfs_orig_write_end_io+0x51/0x90 [btrfs]
   dm_submit_bio+0x5c2/0xa50 [dm_mod]
   ? find_held_lock+0x2b/0x80
   ? blk_try_enter_queue+0x90/0x1e0
   __submit_bio+0xe0/0x130
   ? ktime_get+0x10a/0x160
   ? lockdep_hardirqs_on+0x74/0x100
   submit_bio_noacct_nocheck+0x199/0x410
   btrfs_submit_bio+0x7d/0x150 [btrfs]
   btrfs_submit_chunk+0x1a1/0x6d0 [btrfs]
   ? lockdep_hardirqs_on+0x74/0x100
   ? __folio_start_writeback+0x10/0x2c0
   btrfs_submit_bbio+0x1c/0x40 [btrfs]
   submit_one_bio+0x44/0x60 [btrfs]
   submit_extent_folio+0x13f/0x330 [btrfs]
   ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs]
   extent_writepage_io+0x18b/0x360 [btrfs]
   extent_write_locked_range+0x17c/0x340 [btrfs]
   ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs]
   run_delalloc_cow+0x71/0xd0 [btrfs]
   btrfs_run_delalloc_range+0x176/0x500 [btrfs]
   ? find_lock_delalloc_range+0x119/0x260 [btrfs]
   writepage_delalloc+0x2ab/0x480 [btrfs]
   extent_write_cache_pages+0x236/0x7d0 [btrfs]
   btrfs_writepages+0x72/0x130 [btrfs]
   do_writepages+0xd4/0x240
   ? find_held_lock+0x2b/0x80
   ? wbc_attach_and_unlock_inode+0x12c/0x290
   ? wbc_attach_and_unlock_inode+0x12c/0x290
   __writeback_single_inode+0x5c/0x4c0
   ? do_raw_spin_unlock+0x49/0xb0
   writeback_sb_inodes+0x22c/0x560
   __writeback_inodes_wb+0x4c/0xe0
   wb_writeback+0x1d6/0x3f0
   wb_workfn+0x334/0x520
   process_one_work+0x1ee/0x570
   ? lock_is_held_type+0xc6/0x130
   worker_thread+0x1d1/0x3b0
   ? __pfx_worker_thread+0x10/0x10
   kthread+0xee/0x120
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x30/0x50
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>
  Modules linked in: dm_mod btrfs blake2b_generic xor raid6_pq rapl
  CR2: 0000000000000020

* Case 2. Earlier completion of orig_bbio for mirrored btrfs_bios

btrfs_bbio_propagate_error() assumes the end_io function for orig_bbio is
called last among split bios. In that case, btrfs_orig_write_end_io() sets
the bio->bi_status to BLK_STS_IOERR by seeing the bioc->error [2].
Otherwise, the increased orig_bio's bioc->error is not checked by anyone
and return BLK_STS_OK to the upper layer.

[2] Actually, this is not true. Because we only increases orig_bioc->errors
by max_errors, the condition "atomic_read(&bioc->error) > bioc->max_errors"
is still not met if only one split btrfs_bio fails.

* Case 3. Later completion of orig_bbio for un-mirrored btrfs_bios

In contrast to the above case, btrfs_bbio_propagate_error() is not working
well if un-mirrored orig_bbio is completed last. It sets
orig_bbio->bio.bi_status to the btrfs_bio's error. But, that is easily
over-written by orig_bbio's completion status. If the status is BLK_STS_OK,
the upper layer would not know the failure.

* Solution

Considering the above cases, we can only save the error status in the
orig_bbio (remaining part after split) itself as it is always
available. Also, the saved error status should be propagated when all the
split btrfs_bios are finished (i.e, bbio->pending_ios == 0).

This commit introduces "status" to btrfs_bbio and saves the first error of
split bios to original btrfs_bio's "status" variable. When all the split
bios are finished, the saved status is loaded into original btrfs_bio's
status.

With this commit, btrfs/146 on zoned devices does not hit the NULL pointer
dereference anymore.

Fixes: 852eee6 ("btrfs: allow btrfs_submit_bio to split bios")
CC: stable@vger.kernel.org # 6.6+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
boryas pushed a commit that referenced this pull request Mar 11, 2025
For the ACPI backend of UCSI the UCSI "registers" are just a memory copy
of the register values in an opregion. The ACPI implementation in the
BIOS ensures that the opregion contents are synced to the embedded
controller and it ensures that the registers (in particular CCI) are
synced back to the opregion on notifications. While there is an ACPI call
that syncs the actual registers to the opregion there is rarely a need to
do this and on some ACPI implementations it actually breaks in various
interesting ways.

The only reason to force a sync from the embedded controller is to poll
CCI while notifications are disabled. Only the ucsi core knows if this
is the case and guessing based on the current command is suboptimal, i.e.
leading to the following spurious assertion splat:

WARNING: CPU: 3 PID: 76 at drivers/usb/typec/ucsi/ucsi.c:1388 ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi]
CPU: 3 UID: 0 PID: 76 Comm: kworker/3:0 Not tainted 6.12.11-200.fc41.x86_64 #1
Hardware name: LENOVO 21D0/LNVNB161216, BIOS J6CN45WW 03/17/2023
Workqueue: events_long ucsi_init_work [typec_ucsi]
RIP: 0010:ucsi_reset_ppm+0x1b4/0x1c0 [typec_ucsi]
Call Trace:
 <TASK>
 ucsi_init_work+0x3c/0xac0 [typec_ucsi]
 process_one_work+0x179/0x330
 worker_thread+0x252/0x390
 kthread+0xd2/0x100
 ret_from_fork+0x34/0x50
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Thus introduce a ->poll_cci() method that works like ->read_cci() with an
additional forced sync and document that this should be used when polling
with notifications disabled. For all other backends that presumably don't
have this issue use the same implementation for both methods.

Fixes: fa48d7e ("usb: typec: ucsi: Do not call ACPI _DSM method for UCSI read operations")
Cc: stable <stable@kernel.org>
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
Tested-by: Fedor Pchelkin <boddah8794@gmail.com>
Signed-off-by: Fedor Pchelkin <boddah8794@gmail.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20250217105442.113486-2-boddah8794@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
Devices created through binderfs are added to the global binder_devices
list but are not removed before being destroyed. This leads to dangling
pointers in the list and subsequent use-after-free errors:

  ==================================================================
  BUG: KASAN: slab-use-after-free in binder_add_device+0x5c/0x9c
  Write of size 8 at addr ffff0000c258d708 by task mount/653

  CPU: 7 UID: 0 PID: 653 Comm: mount Not tainted 6.13.0-09030-g6d61a53dd6f5 #1
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   binder_add_device+0x5c/0x9c
   binderfs_binder_device_create+0x690/0x84c
   [...]
   __arm64_sys_mount+0x324/0x3bc

  Allocated by task 632:
   binderfs_binder_device_create+0x168/0x84c
   binder_ctl_ioctl+0xfc/0x184
   [...]
   __arm64_sys_ioctl+0x110/0x150

  Freed by task 649:
   kfree+0xe0/0x338
   binderfs_evict_inode+0x138/0x1dc
   [...]
  ==================================================================

Remove devices from binder_devices before destroying them.

Cc: Li Li <dualli@google.com>
Reported-by: syzbot+7015dcf45953112c8b45@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7015dcf45953112c8b45
Fixes: 12d909c ("binderfs: add new binder devices to binder_devices")
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Tested-by: syzbot+7015dcf45953112c8b45@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20250130215823.1518990-1-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
nvme_tcp_poll() may race with the send path error handler because
it may complete the request while it is actively being polled for
completion, resulting in a UAF panic [1]:

We should make sure to stop polling when we see an error when
trying to read from the socket. Hence make sure to propagate the
error so that the block layer breaks the polling cycle.

[1]:
--
[35665.692310] nvme nvme2: failed to send request -13
[35665.702265] nvme nvme2: unsupported pdu type (3)
[35665.702272] BUG: kernel NULL pointer dereference, address: 0000000000000000
[35665.702542] nvme nvme2: queue 1 receive failed:  -22
[35665.703209] #PF: supervisor write access in kernel mode
[35665.703213] #PF: error_code(0x0002) - not-present page
[35665.703214] PGD 8000003801cce067 P4D 8000003801cce067 PUD 37e6f79067 PMD 0
[35665.703220] Oops: 0002 [#1] SMP PTI
[35665.703658] nvme nvme2: starting error recovery
[35665.705809] Hardware name: Inspur aaabbb/YZMB-00882-104, BIOS 4.1.26 09/22/2022
[35665.705812] Workqueue: kblockd blk_mq_requeue_work
[35665.709172] RIP: 0010:_raw_spin_lock+0xc/0x30
[35665.715788] Call Trace:
[35665.716201]  <TASK>
[35665.716613]  ? show_trace_log_lvl+0x1c1/0x2d9
[35665.717049]  ? show_trace_log_lvl+0x1c1/0x2d9
[35665.717457]  ? blk_mq_request_bypass_insert+0x2c/0xb0
[35665.717950]  ? __die_body.cold+0x8/0xd
[35665.718361]  ? page_fault_oops+0xac/0x140
[35665.718749]  ? blk_mq_start_request+0x30/0xf0
[35665.719144]  ? nvme_tcp_queue_rq+0xc7/0x170 [nvme_tcp]
[35665.719547]  ? exc_page_fault+0x62/0x130
[35665.719938]  ? asm_exc_page_fault+0x22/0x30
[35665.720333]  ? _raw_spin_lock+0xc/0x30
[35665.720723]  blk_mq_request_bypass_insert+0x2c/0xb0
[35665.721101]  blk_mq_requeue_work+0xa5/0x180
[35665.721451]  process_one_work+0x1e8/0x390
[35665.721809]  worker_thread+0x53/0x3d0
[35665.722159]  ? process_one_work+0x390/0x390
[35665.722501]  kthread+0x124/0x150
[35665.722849]  ? set_kthread_struct+0x50/0x50
[35665.723182]  ret_from_fork+0x1f/0x30

Reported-by: Zhang Guanghui <zhang.guanghui@cestc.cn>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
syzbot is able to crash hosts [1], using llc and devices
not supporting IFF_TX_SKB_SHARING.

In this case, e1000 driver calls eth_skb_pad(), while
the skb is shared.

Simply replace skb_get() by skb_clone() in net/llc/llc_s_ac.c

Note that e1000 driver might have an issue with pktgen,
because it does not clear IFF_TX_SKB_SHARING, this is an
orthogonal change.

We need to audit other skb_get() uses in net/llc.

[1]

kernel BUG at net/core/skbuff.c:2178 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 16371 Comm: syz.2.2764 Not tainted 6.14.0-rc4-syzkaller-00052-gac9c34d1e45a #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
 RIP: 0010:pskb_expand_head+0x6ce/0x1240 net/core/skbuff.c:2178
Call Trace:
 <TASK>
  __skb_pad+0x18a/0x610 net/core/skbuff.c:2466
  __skb_put_padto include/linux/skbuff.h:3843 [inline]
  skb_put_padto include/linux/skbuff.h:3862 [inline]
  eth_skb_pad include/linux/etherdevice.h:656 [inline]
  e1000_xmit_frame+0x2d99/0x5800 drivers/net/ethernet/intel/e1000/e1000_main.c:3128
  __netdev_start_xmit include/linux/netdevice.h:5151 [inline]
  netdev_start_xmit include/linux/netdevice.h:5160 [inline]
  xmit_one net/core/dev.c:3806 [inline]
  dev_hard_start_xmit+0x9a/0x7b0 net/core/dev.c:3822
  sch_direct_xmit+0x1ae/0xc30 net/sched/sch_generic.c:343
  __dev_xmit_skb net/core/dev.c:4045 [inline]
  __dev_queue_xmit+0x13d4/0x43e0 net/core/dev.c:4621
  dev_queue_xmit include/linux/netdevice.h:3313 [inline]
  llc_sap_action_send_test_c+0x268/0x320 net/llc/llc_s_ac.c:144
  llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [inline]
  llc_sap_next_state net/llc/llc_sap.c:182 [inline]
  llc_sap_state_process+0x239/0x510 net/llc/llc_sap.c:209
  llc_ui_sendmsg+0xd0d/0x14e0 net/llc/af_llc.c:993
  sock_sendmsg_nosec net/socket.c:718 [inline]

Fixes: 1da177e ("Linux-2.6.12-rc2")
Reported-by: syzbot+da65c993ae113742a25f@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67c020c0.050a0220.222324.0011.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
boryas pushed a commit that referenced this pull request Mar 11, 2025
Currently kvfree_rcu() APIs use a system workqueue which is
"system_unbound_wq" to driver RCU machinery to reclaim a memory.

Recently, it has been noted that the following kernel warning can
be observed:

<snip>
workqueue: WQ_MEM_RECLAIM nvme-wq:nvme_scan_work is flushing !WQ_MEM_RECLAIM events_unbound:kfree_rcu_work
  WARNING: CPU: 21 PID: 330 at kernel/workqueue.c:3719 check_flush_dependency+0x112/0x120
  Modules linked in: intel_uncore_frequency(E) intel_uncore_frequency_common(E) skx_edac(E) ...
  CPU: 21 UID: 0 PID: 330 Comm: kworker/u144:6 Tainted: G            E      6.13.2-0_g925d379822da #1
  Hardware name: Wiwynn Twin Lakes MP/Twin Lakes Passive MP, BIOS YMM20 02/01/2023
  Workqueue: nvme-wq nvme_scan_work
  RIP: 0010:check_flush_dependency+0x112/0x120
  Code: 05 9a 40 14 02 01 48 81 c6 c0 00 00 00 48 8b 50 18 48 81 c7 c0 00 00 00 48 89 f9 48 ...
  RSP: 0018:ffffc90000df7bd8 EFLAGS: 00010082
  RAX: 000000000000006a RBX: ffffffff81622390 RCX: 0000000000000027
  RDX: 00000000fffeffff RSI: 000000000057ffa8 RDI: ffff88907f960c88
  RBP: 0000000000000000 R08: ffffffff83068e50 R09: 000000000002fffd
  R10: 0000000000000004 R11: 0000000000000000 R12: ffff8881001a4400
  R13: 0000000000000000 R14: ffff88907f420fb8 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff88907f940000(0000) knlGS:0000000000000000
  CR2: 00007f60c3001000 CR3: 000000107d010005 CR4: 00000000007726f0
  PKRU: 55555554
  Call Trace:
   <TASK>
   ? __warn+0xa4/0x140
   ? check_flush_dependency+0x112/0x120
   ? report_bug+0xe1/0x140
   ? check_flush_dependency+0x112/0x120
   ? handle_bug+0x5e/0x90
   ? exc_invalid_op+0x16/0x40
   ? asm_exc_invalid_op+0x16/0x20
   ? timer_recalc_next_expiry+0x190/0x190
   ? check_flush_dependency+0x112/0x120
   ? check_flush_dependency+0x112/0x120
   __flush_work.llvm.1643880146586177030+0x174/0x2c0
   flush_rcu_work+0x28/0x30
   kvfree_rcu_barrier+0x12f/0x160
   kmem_cache_destroy+0x18/0x120
   bioset_exit+0x10c/0x150
   disk_release.llvm.6740012984264378178+0x61/0xd0
   device_release+0x4f/0x90
   kobject_put+0x95/0x180
   nvme_put_ns+0x23/0xc0
   nvme_remove_invalid_namespaces+0xb3/0xd0
   nvme_scan_work+0x342/0x490
   process_scheduled_works+0x1a2/0x370
   worker_thread+0x2ff/0x390
   ? pwq_release_workfn+0x1e0/0x1e0
   kthread+0xb1/0xe0
   ? __kthread_parkme+0x70/0x70
   ret_from_fork+0x30/0x40
   ? __kthread_parkme+0x70/0x70
   ret_from_fork_asm+0x11/0x20
   </TASK>
  ---[ end trace 0000000000000000 ]---
<snip>

To address this switch to use of independent WQ_MEM_RECLAIM
workqueue, so the rules are not violated from workqueue framework
point of view.

Apart of that, since kvfree_rcu() does reclaim memory it is worth
to go with WQ_MEM_RECLAIM type of wq because it is designed for
this purpose.

Fixes: 6c6c47b ("mm, slab: call kvfree_rcu_barrier() from kmem_cache_destroy()"),
Reported-by: Keith Busch <kbusch@kernel.org>
Closes: https://lore.kernel.org/all/Z7iqJtCjHKfo8Kho@kbusch-mbp/
Cc: stable@vger.kernel.org
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
boryas pushed a commit that referenced this pull request Mar 11, 2025
Use raw_spinlock in order to fix spurious messages about invalid context
when spinlock debugging is enabled. The lock is only used to serialize
register access.

    [    4.239592] =============================
    [    4.239595] [ BUG: Invalid wait context ]
    [    4.239599] 6.13.0-rc7-arm64-renesas-05496-gd088502a519f torvalds#35 Not tainted
    [    4.239603] -----------------------------
    [    4.239606] kworker/u8:5/76 is trying to lock:
    [    4.239609] ffff0000091898a0 (&p->lock){....}-{3:3}, at: gpio_rcar_config_interrupt_input_mode+0x34/0x164
    [    4.239641] other info that might help us debug this:
    [    4.239643] context-{5:5}
    [    4.239646] 5 locks held by kworker/u8:5/76:
    [    4.239651]  #0: ffff0000080fb148 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x190/0x62c
    [    4.250180] OF: /soc/sound@ec500000/ports/port@0/endpoint: Read of boolean property 'frame-master' with a value.
    [    4.254094]  #1: ffff80008299bd80 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1b8/0x62c
    [    4.254109]  #2: ffff00000920c8f8
    [    4.258345] OF: /soc/sound@ec500000/ports/port@1/endpoint: Read of boolean property 'bitclock-master' with a value.
    [    4.264803]  (&dev->mutex){....}-{4:4}, at: __device_attach_async_helper+0x3c/0xdc
    [    4.264820]  #3: ffff00000a50ca40 (request_class#2){+.+.}-{4:4}, at: __setup_irq+0xa0/0x690
    [    4.264840]  #4:
    [    4.268872] OF: /soc/sound@ec500000/ports/port@1/endpoint: Read of boolean property 'frame-master' with a value.
    [    4.273275] ffff00000a50c8c8 (lock_class){....}-{2:2}, at: __setup_irq+0xc4/0x690
    [    4.296130] renesas_sdhi_internal_dmac ee10000.mmc: mmc1 base at 0x00000000ee100000, max clock rate 200 MHz
    [    4.304082] stack backtrace:
    [    4.304086] CPU: 1 UID: 0 PID: 76 Comm: kworker/u8:5 Not tainted 6.13.0-rc7-arm64-renesas-05496-gd088502a519f torvalds#35
    [    4.304092] Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT)
    [    4.304097] Workqueue: async async_run_entry_fn
    [    4.304106] Call trace:
    [    4.304110]  show_stack+0x14/0x20 (C)
    [    4.304122]  dump_stack_lvl+0x6c/0x90
    [    4.304131]  dump_stack+0x14/0x1c
    [    4.304138]  __lock_acquire+0xdfc/0x1584
    [    4.426274]  lock_acquire+0x1c4/0x33c
    [    4.429942]  _raw_spin_lock_irqsave+0x5c/0x80
    [    4.434307]  gpio_rcar_config_interrupt_input_mode+0x34/0x164
    [    4.440061]  gpio_rcar_irq_set_type+0xd4/0xd8
    [    4.444422]  __irq_set_trigger+0x5c/0x178
    [    4.448435]  __setup_irq+0x2e4/0x690
    [    4.452012]  request_threaded_irq+0xc4/0x190
    [    4.456285]  devm_request_threaded_irq+0x7c/0xf4
    [    4.459398] ata1: link resume succeeded after 1 retries
    [    4.460902]  mmc_gpiod_request_cd_irq+0x68/0xe0
    [    4.470660]  mmc_start_host+0x50/0xac
    [    4.474327]  mmc_add_host+0x80/0xe4
    [    4.477817]  tmio_mmc_host_probe+0x2b0/0x440
    [    4.482094]  renesas_sdhi_probe+0x488/0x6f4
    [    4.486281]  renesas_sdhi_internal_dmac_probe+0x60/0x78
    [    4.491509]  platform_probe+0x64/0xd8
    [    4.495178]  really_probe+0xb8/0x2a8
    [    4.498756]  __driver_probe_device+0x74/0x118
    [    4.503116]  driver_probe_device+0x3c/0x154
    [    4.507303]  __device_attach_driver+0xd4/0x160
    [    4.511750]  bus_for_each_drv+0x84/0xe0
    [    4.515588]  __device_attach_async_helper+0xb0/0xdc
    [    4.520470]  async_run_entry_fn+0x30/0xd8
    [    4.524481]  process_one_work+0x210/0x62c
    [    4.528494]  worker_thread+0x1ac/0x340
    [    4.532245]  kthread+0x10c/0x110
    [    4.535476]  ret_from_fork+0x10/0x20

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250121135833.3769310-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
Commit b15c872 ("hwpoison, memory_hotplug: allow hwpoisoned pages to
be offlined) add page poison checks in do_migrate_range in order to make
offline hwpoisoned page possible by introducing isolate_lru_page and
try_to_unmap for hwpoisoned page.  However folio lock must be held before
calling try_to_unmap.  Add it to fix this problem.

Warning will be produced if folio is not locked during unmap:

  ------------[ cut here ]------------
  kernel BUG at ./include/linux/swapops.h:400!
  Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
  Modules linked in:
  CPU: 4 UID: 0 PID: 411 Comm: bash Tainted: G        W          6.13.0-rc1-00016-g3c434c7ee82a-dirty torvalds#41
  Tainted: [W]=WARN
  Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
  pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  pc : try_to_unmap_one+0xb08/0xd3c
  lr : try_to_unmap_one+0x3dc/0xd3c
  Call trace:
   try_to_unmap_one+0xb08/0xd3c (P)
   try_to_unmap_one+0x3dc/0xd3c (L)
   rmap_walk_anon+0xdc/0x1f8
   rmap_walk+0x3c/0x58
   try_to_unmap+0x88/0x90
   unmap_poisoned_folio+0x30/0xa8
   do_migrate_range+0x4a0/0x568
   offline_pages+0x5a4/0x670
   memory_block_action+0x17c/0x374
   memory_subsys_offline+0x3c/0x78
   device_offline+0xa4/0xd0
   state_store+0x8c/0xf0
   dev_attr_store+0x18/0x2c
   sysfs_kf_write+0x44/0x54
   kernfs_fop_write_iter+0x118/0x1a8
   vfs_write+0x3a8/0x4bc
   ksys_write+0x6c/0xf8
   __arm64_sys_write+0x1c/0x28
   invoke_syscall+0x44/0x100
   el0_svc_common.constprop.0+0x40/0xe0
   do_el0_svc+0x1c/0x28
   el0_svc+0x30/0xd0
   el0t_64_sync_handler+0xc8/0xcc
   el0t_64_sync+0x198/0x19c
  Code: f9407be0 b5fff320 d4210000 17ffff97 (d4210000)
  ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20250217014329.3610326-4-mawupeng1@huawei.com
Fixes: b15c872 ("hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined")
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
Add a NULL check on the return value of swp_swap_info in __swap_duplicate
to prevent crashes caused by NULL pointer dereference.

The reason why swp_swap_info() returns NULL is unclear; it may be due
to CPU cache issues or DDR bit flips.  The probability of this issue is
very small - it has been observed to occur approximately 1 in 500,000
times per week.  The stack info we encountered is as follows:

Unable to handle kernel NULL pointer dereference at virtual address
0000000000000058
[RB/E]rb_sreason_str_set: sreason_str set null_pointer
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 39-bit VAs, pgdp=00000008a80e5000
[0000000000000058] pgd=0000000000000000, p4d=0000000000000000,
pud=0000000000000000
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Skip md ftrace buffer dump for: 0x1609e0
...
pc : swap_duplicate+0x44/0x164
lr : copy_page_range+0x508/0x1e78
sp : ffffffc0f2a699e0
x29: ffffffc0f2a699e0 x28: ffffff8a5b28d388 x27: ffffff8b06603388
x26: ffffffdf7291fe70 x25: 0000000000000006 x24: 0000000000100073
x23: 00000000002d2d2f x22: 0000000000000008 x21: 0000000000000000
x20: 00000000002d2d2f x19: 18000000002d2d2f x18: ffffffdf726faec0
x17: 0000000000000000 x16: 0010000000000001 x15: 0040000000000001
x14: 0400000000000001 x13: ff7ffffffffffb7f x12: ffeffffffffffbff
x11: ffffff8a5c7e1898 x10: 0000000000000018 x9 : 0000000000000006
x8 : 1800000000000000 x7 : 0000000000000000 x6 : ffffff8057c01f10
x5 : 000000000000a318 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000006daf200000 x1 : 0000000000000001 x0 : 18000000002d2d2f
Call trace:
 swap_duplicate+0x44/0x164
 copy_page_range+0x508/0x1e78
 copy_process+0x1278/0x21cc
 kernel_clone+0x90/0x438
 __arm64_sys_clone+0x5c/0x8c
 invoke_syscall+0x58/0x110
 do_el0_svc+0x8c/0xe0
 el0_svc+0x38/0x9c
 el0t_64_sync_handler+0x44/0xec
 el0t_64_sync+0x1a8/0x1ac
Code: 9139c35a 71006f3f 54000568 f8797b55 (f9402ea8)
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Oops: Fatal exception
SMP: stopping secondary CPUs

The patch seems to only provide a workaround, but there are no more
effective software solutions to handle the bit flips problem.  This path
will change the issue from a system crash to a process exception, thereby
reducing the impact on the entire machine.

akpm: this is probably a kernel bug, but this patch keeps the system
running and doesn't reduce that bug's debuggability.

Link: https://lkml.kernel.org/r/e223b0e6ba2f4924984b1917cc717bd5@honor.com
Signed-off-by: gao xu <gaoxu2@honor.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
userfaultfd_move() checks whether the PTE entry is present or a
swap entry.

- If the PTE entry is present, move_present_pte() handles folio
  migration by setting:

  src_folio->index = linear_page_index(dst_vma, dst_addr);

- If the PTE entry is a swap entry, move_swap_pte() simply copies
  the PTE to the new dst_addr.

This approach is incorrect because, even if the PTE is a swap entry,
it can still reference a folio that remains in the swap cache.

This creates a race window between steps 2 and 4.
 1. add_to_swap: The folio is added to the swapcache.
 2. try_to_unmap: PTEs are converted to swap entries.
 3. pageout: The folio is written back.
 4. Swapcache is cleared.
If userfaultfd_move() occurs in the window between steps 2 and 4,
after the swap PTE has been moved to the destination, accessing the
destination triggers do_swap_page(), which may locate the folio in
the swapcache. However, since the folio's index has not been updated
to match the destination VMA, do_swap_page() will detect a mismatch.

This can result in two critical issues depending on the system
configuration.

If KSM is disabled, both small and large folios can trigger a BUG
during the add_rmap operation due to:

 page_pgoff(folio, page) != linear_page_index(vma, address)

[   13.336953] page: refcount:6 mapcount:1 mapping:00000000f43db19c index:0xffffaf150 pfn:0x4667c
[   13.337520] head: order:2 mapcount:1 entire_mapcount:0 nr_pages_mapped:1 pincount:0
[   13.337716] memcg:ffff00000405f000
[   13.337849] anon flags: 0x3fffc0000020459(locked|uptodate|dirty|owner_priv_1|head|swapbacked|node=0|zone=0|lastcpupid=0xffff)
[   13.338630] raw: 03fffc0000020459 ffff80008507b538 ffff80008507b538 ffff000006260361
[   13.338831] raw: 0000000ffffaf150 0000000000004000 0000000600000000 ffff00000405f000
[   13.339031] head: 03fffc0000020459 ffff80008507b538 ffff80008507b538 ffff000006260361
[   13.339204] head: 0000000ffffaf150 0000000000004000 0000000600000000 ffff00000405f000
[   13.339375] head: 03fffc0000000202 fffffdffc0199f01 ffffffff00000000 0000000000000001
[   13.339546] head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
[   13.339736] page dumped because: VM_BUG_ON_PAGE(page_pgoff(folio, page) != linear_page_index(vma, address))
[   13.340190] ------------[ cut here ]------------
[   13.340316] kernel BUG at mm/rmap.c:1380!
[   13.340683] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
[   13.340969] Modules linked in:
[   13.341257] CPU: 1 UID: 0 PID: 107 Comm: a.out Not tainted 6.14.0-rc3-gcf42737e247a-dirty torvalds#299
[   13.341470] Hardware name: linux,dummy-virt (DT)
[   13.341671] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   13.341815] pc : __page_check_anon_rmap+0xa0/0xb0
[   13.341920] lr : __page_check_anon_rmap+0xa0/0xb0
[   13.342018] sp : ffff80008752bb20
[   13.342093] x29: ffff80008752bb20 x28: fffffdffc0199f00 x27: 0000000000000001
[   13.342404] x26: 0000000000000000 x25: 0000000000000001 x24: 0000000000000001
[   13.342575] x23: 0000ffffaf0d0000 x22: 0000ffffaf0d0000 x21: fffffdffc0199f00
[   13.342731] x20: fffffdffc0199f00 x19: ffff000006210700 x18: 00000000ffffffff
[   13.342881] x17: 6c203d2120296567 x16: 6170202c6f696c6f x15: 662866666f67705f
[   13.343033] x14: 6567617028454741 x13: 2929737365726464 x12: ffff800083728ab0
[   13.343183] x11: ffff800082996bf8 x10: 0000000000000fd7 x9 : ffff80008011bc40
[   13.343351] x8 : 0000000000017fe8 x7 : 00000000fffff000 x6 : ffff8000829eebf8
[   13.343498] x5 : c0000000fffff000 x4 : 0000000000000000 x3 : 0000000000000000
[   13.343645] x2 : 0000000000000000 x1 : ffff0000062db980 x0 : 000000000000005f
[   13.343876] Call trace:
[   13.344045]  __page_check_anon_rmap+0xa0/0xb0 (P)
[   13.344234]  folio_add_anon_rmap_ptes+0x22c/0x320
[   13.344333]  do_swap_page+0x1060/0x1400
[   13.344417]  __handle_mm_fault+0x61c/0xbc8
[   13.344504]  handle_mm_fault+0xd8/0x2e8
[   13.344586]  do_page_fault+0x20c/0x770
[   13.344673]  do_translation_fault+0xb4/0xf0
[   13.344759]  do_mem_abort+0x48/0xa0
[   13.344842]  el0_da+0x58/0x130
[   13.344914]  el0t_64_sync_handler+0xc4/0x138
[   13.345002]  el0t_64_sync+0x1ac/0x1b0
[   13.345208] Code: aa1503e0 f000f801 910f6021 97ff5779 (d4210000)
[   13.345504] ---[ end trace 0000000000000000 ]---
[   13.345715] note: a.out[107] exited with irqs disabled
[   13.345954] note: a.out[107] exited with preempt_count 2

If KSM is enabled, Peter Xu also discovered that do_swap_page() may
trigger an unexpected CoW operation for small folios because
ksm_might_need_to_copy() allocates a new folio when the folio index
does not match linear_page_index(vma, addr).

This patch also checks the swapcache when handling swap entries. If a
match is found in the swapcache, it processes it similarly to a present
PTE.
However, there are some differences. For example, the folio is no longer
exclusive because folio_try_share_anon_rmap_pte() is performed during
unmapping.
Furthermore, in the case of swapcache, the folio has already been
unmapped, eliminating the risk of concurrent rmap walks and removing the
need to acquire src_folio's anon_vma or lock.

Note that for large folios, in the swapcache handling path, we directly
return -EBUSY since split_folio() will return -EBUSY regardless if
the folio is under writeback or unmapped. This is not an urgent issue,
so a follow-up patch may address it separately.

[v-songbaohua@oppo.com: minor cleanup according to Peter Xu]
  Link: https://lkml.kernel.org/r/20250226024411.47092-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20250226001400.9129-1-21cnbao@gmail.com
Fixes: adef440 ("userfaultfd: UFFDIO_MOVE uABI")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nicolas Geoffray <ngeoffray@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: ZhangPeng <zhangpeng362@huawei.com>
Cc: Tangquan Zheng <zhengtangquan@oppo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Mar 11, 2025
With ltp test case "testcases/bin/hugefork02", there is a dmesg error
report message such as:

 kernel BUG at mm/hugetlb.c:5550!
 Oops - BUG[#1]:
 CPU: 0 UID: 0 PID: 1517 Comm: hugefork02 Not tainted 6.14.0-rc2+ torvalds#241
 Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
 pc 90000000004eaf1c ra 9000000000485538 tp 900000010edbc000 sp 900000010edbf940
 a0 900000010edbfb00 a1 9000000108d20280 a2 00007fffe9474000 a3 00007ffff3474000
 a4 0000000000000000 a5 0000000000000003 a6 00000000003cadd3 a7 0000000000000000
 t0 0000000001ffffff t1 0000000001474000 t2 900000010ecd7900 t3 00007fffe9474000
 t4 00007fffe9474000 t5 0000000000000040 t6 900000010edbfb00 t7 0000000000000001
 t8 0000000000000005 u0 90000000004849d0 s9 900000010edbfa00 s0 9000000108d20280
 s1 00007fffe9474000 s2 0000000002000000 s3 9000000108d20280 s4 9000000002b38b10
 s5 900000010edbfb00 s6 00007ffff3474000 s7 0000000000000406 s8 900000010edbfa08
    ra: 9000000000485538 unmap_vmas+0x130/0x218
   ERA: 90000000004eaf1c __unmap_hugepage_range+0x6f4/0x7d0
  PRMD: 00000004 (PPLV0 +PIE -PWE)
  EUEN: 00000007 (+FPE +SXE +ASXE -BTE)
  ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
 ESTAT: 000c0000 [BRK] (IS= ECode=12 EsubCode=0)
 PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
 Process hugefork02 (pid: 1517, threadinfo=00000000a670eaf4, task=000000007a95fc64)
 Call Trace:
 [<90000000004eaf1c>] __unmap_hugepage_range+0x6f4/0x7d0
 [<9000000000485534>] unmap_vmas+0x12c/0x218
 [<9000000000494068>] exit_mmap+0xe0/0x308
 [<900000000025fdc4>] mmput+0x74/0x180
 [<900000000026a284>] do_exit+0x294/0x898
 [<900000000026aa30>] do_group_exit+0x30/0x98
 [<900000000027bed4>] get_signal+0x83c/0x868
 [<90000000002457b4>] arch_do_signal_or_restart+0x54/0xfa0
 [<90000000015795e8>] irqentry_exit_to_user_mode+0xb8/0x138
 [<90000000002572d0>] tlb_do_page_fault_1+0x114/0x1b4

The problem is that base address allocated from hugetlbfs is not aligned
with pmd size. Here add a checking for hugetlbfs and align base address
with pmd size. After this patch the test case "testcases/bin/hugefork02"
passes to run.

This is similar to the commit 7f24cbc ("mm/mmap: teach
generic_get_unmapped_area{_topdown} to handle hugetlb mappings").

Cc: stable@vger.kernel.org  # 6.13+
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
boryas pushed a commit that referenced this pull request Apr 3, 2025
…cal section

A circular lock dependency splat has been seen involving down_trylock():

  ======================================================
  WARNING: possible circular locking dependency detected
  6.12.0-41.el10.s390x+debug
  ------------------------------------------------------
  dd/32479 is trying to acquire lock:
  0015a20accd0d4f8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x26/0x90

  but task is already holding lock:
  000000017e461698 (&zone->lock){-.-.}-{2:2}, at: rmqueue_bulk+0xac/0x8f0

  the existing dependency chain (in reverse order) is:
  -> #4 (&zone->lock){-.-.}-{2:2}:
  -> #3 (hrtimer_bases.lock){-.-.}-{2:2}:
  -> #2 (&rq->__lock){-.-.}-{2:2}:
  -> #1 (&p->pi_lock){-.-.}-{2:2}:
  -> #0 ((console_sem).lock){-.-.}-{2:2}:

The console_sem -> pi_lock dependency is due to calling try_to_wake_up()
while holding the console_sem raw_spinlock. This dependency can be broken
by using wake_q to do the wakeup instead of calling try_to_wake_up()
under the console_sem lock. This will also make the semaphore's
raw_spinlock become a terminal lock without taking any further locks
underneath it.

The hrtimer_bases.lock is a raw_spinlock while zone->lock is a
spinlock. The hrtimer_bases.lock -> zone->lock dependency happens via
the debug_objects_fill_pool() helper function in the debugobjects code.

  -> #4 (&zone->lock){-.-.}-{2:2}:
         __lock_acquire+0xe86/0x1cc0
         lock_acquire.part.0+0x258/0x630
         lock_acquire+0xb8/0xe0
         _raw_spin_lock_irqsave+0xb4/0x120
         rmqueue_bulk+0xac/0x8f0
         __rmqueue_pcplist+0x580/0x830
         rmqueue_pcplist+0xfc/0x470
         rmqueue.isra.0+0xdec/0x11b0
         get_page_from_freelist+0x2ee/0xeb0
         __alloc_pages_noprof+0x2c2/0x520
         alloc_pages_mpol_noprof+0x1fc/0x4d0
         alloc_pages_noprof+0x8c/0xe0
         allocate_slab+0x320/0x460
         ___slab_alloc+0xa58/0x12b0
         __slab_alloc.isra.0+0x42/0x60
         kmem_cache_alloc_noprof+0x304/0x350
         fill_pool+0xf6/0x450
         debug_object_activate+0xfe/0x360
         enqueue_hrtimer+0x34/0x190
         __run_hrtimer+0x3c8/0x4c0
         __hrtimer_run_queues+0x1b2/0x260
         hrtimer_interrupt+0x316/0x760
         do_IRQ+0x9a/0xe0
         do_irq_async+0xf6/0x160

Normally a raw_spinlock to spinlock dependency is not legitimate
and will be warned if CONFIG_PROVE_RAW_LOCK_NESTING is enabled,
but debug_objects_fill_pool() is an exception as it explicitly
allows this dependency for non-PREEMPT_RT kernel without causing
PROVE_RAW_LOCK_NESTING lockdep splat. As a result, this dependency is
legitimate and not a bug.

Anyway, semaphore is the only locking primitive left that is still
using try_to_wake_up() to do wakeup inside critical section, all the
other locking primitives had been migrated to use wake_q to do wakeup
outside of the critical section. It is also possible that there are
other circular locking dependencies involving printk/console_sem or
other existing/new semaphores lurking somewhere which may show up in
the future. Let just do the migration now to wake_q to avoid headache
like this.

Reported-by: yzbot+ed801a886dfdbfe7136d@syzkaller.appspotmail.com
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250307232717.1759087-3-boqun.feng@gmail.com
boryas pushed a commit that referenced this pull request Apr 3, 2025
The bnxt_queue_mem_alloc() is called to allocate new queue memory when
a queue is restarted.
It internally accesses rx buffer descriptor corresponding to the index.
The rx buffer descriptor is allocated and set when the interface is up
and it's freed when the interface is down.
So, if queue is restarted if interface is down, kernel panic occurs.

Splat looks like:
 BUG: unable to handle page fault for address: 000000000000b240
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 3 UID: 0 PID: 1563 Comm: ncdevmem2 Not tainted 6.14.0-rc2+ torvalds#9 844ddba6e7c459cafd0bf4db9a3198e
 Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021
 RIP: 0010:bnxt_queue_mem_alloc+0x3f/0x4e0 [bnxt_en]
 Code: 41 54 4d 89 c4 4d 69 c0 c0 05 00 00 55 48 89 f5 53 48 89 fb 4c 8d b5 40 05 00 00 48 83 ec 15
 RSP: 0018:ffff9dcc83fef9e8 EFLAGS: 00010202
 RAX: ffffffffc0457720 RBX: ffff934ed8d40000 RCX: 0000000000000000
 RDX: 000000000000001f RSI: ffff934ea508f800 RDI: ffff934ea508f808
 RBP: ffff934ea508f800 R08: 000000000000b240 R09: ffff934e84f4b000
 R10: ffff9dcc83fefa30 R11: ffff934e84f4b000 R12: 000000000000001f
 R13: ffff934ed8d40ac0 R14: ffff934ea508fd40 R15: ffff934e84f4b000
 FS:  00007fa73888c740(0000) GS:ffff93559f780000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000000000000b240 CR3: 0000000145a2e000 CR4: 00000000007506f0
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? __die+0x20/0x70
  ? page_fault_oops+0x15a/0x460
  ? exc_page_fault+0x6e/0x180
  ? asm_exc_page_fault+0x22/0x30
  ? __pfx_bnxt_queue_mem_alloc+0x10/0x10 [bnxt_en 7f85e76f4d724ba07471d7e39d9e773aea6597b7]
  ? bnxt_queue_mem_alloc+0x3f/0x4e0 [bnxt_en 7f85e76f4d724ba07471d7e39d9e773aea6597b7]
  netdev_rx_queue_restart+0xc5/0x240
  net_devmem_bind_dmabuf_to_queue+0xf8/0x200
  netdev_nl_bind_rx_doit+0x3a7/0x450
  genl_family_rcv_msg_doit+0xd9/0x130
  genl_rcv_msg+0x184/0x2b0
  ? __pfx_netdev_nl_bind_rx_doit+0x10/0x10
  ? __pfx_genl_rcv_msg+0x10/0x10
  netlink_rcv_skb+0x54/0x100
  genl_rcv+0x24/0x40
...

Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Fixes: 2d694c2 ("bnxt_en: implement netdev_queue_mgmt_ops")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250309134219.91670-3-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Apr 3, 2025
When qstats-get operation is executed, callbacks of netdev_stats_ops
are called. The bnxt_get_queue_stats{rx | tx} collect per-queue stats
from sw_stats in the rings.
But {rx | tx | cp}_ring are allocated when the interface is up.
So, these rings are not allocated when the interface is down.

The qstats-get is allowed even if the interface is down. However,
the bnxt_get_queue_stats{rx | tx}() accesses cp_ring and tx_ring
without null check.
So, it needs to avoid accessing rings if the interface is down.

Reproducer:
 ip link set $interface down
 ./cli.py --spec netdev.yaml --dump qstats-get
OR
 ip link set $interface down
 python ./stats.py

Splat looks like:
 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 1680fa067 P4D 1680fa067 PUD 16be3b067 PMD 0
 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 0 UID: 0 PID: 1495 Comm: python3 Not tainted 6.14.0-rc4+ torvalds#32 5cd0f999d5a15c574ac72b3e4b907341
 Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021
 RIP: 0010:bnxt_get_queue_stats_rx+0xf/0x70 [bnxt_en]
 Code: c6 87 b5 18 00 00 02 eb a2 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 01
 RSP: 0018:ffffabef43cdb7e0 EFLAGS: 00010282
 RAX: 0000000000000000 RBX: ffffffffc04c8710 RCX: 0000000000000000
 RDX: ffffabef43cdb858 RSI: 0000000000000000 RDI: ffff8d504e850000
 RBP: ffff8d506c9f9c00 R08: 0000000000000004 R09: ffff8d506bcd901c
 R10: 0000000000000015 R11: ffff8d506bcd9000 R12: 0000000000000000
 R13: ffffabef43cdb8c0 R14: ffff8d504e850000 R15: 0000000000000000
 FS:  00007f2c5462b080(0000) GS:ffff8d575f600000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 0000000167fd0000 CR4: 00000000007506f0
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? __die+0x20/0x70
  ? page_fault_oops+0x15a/0x460
  ? sched_balance_find_src_group+0x58d/0xd10
  ? exc_page_fault+0x6e/0x180
  ? asm_exc_page_fault+0x22/0x30
  ? bnxt_get_queue_stats_rx+0xf/0x70 [bnxt_en cdd546fd48563c280cfd30e9647efa420db07bf1]
  netdev_nl_stats_by_netdev+0x2b1/0x4e0
  ? xas_load+0x9/0xb0
  ? xas_find+0x183/0x1d0
  ? xa_find+0x8b/0xe0
  netdev_nl_qstats_get_dumpit+0xbf/0x1e0
  genl_dumpit+0x31/0x90
  netlink_dump+0x1a8/0x360

Fixes: af7b3b4 ("eth: bnxt: support per-queue statistics")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Link: https://patch.msgid.link/20250309134219.91670-6-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Apr 3, 2025
A blocking notification chain uses a read-write semaphore to protect the
integrity of the chain. The semaphore is acquired for writing when
adding / removing notifiers to / from the chain and acquired for reading
when traversing the chain and informing notifiers about an event.

In case of the blocking switchdev notification chain, recursive
notifications are possible which leads to the semaphore being acquired
twice for reading and to lockdep warnings being generated [1].

Specifically, this can happen when the bridge driver processes a
SWITCHDEV_BRPORT_UNOFFLOADED event which causes it to emit notifications
about deferred events when calling switchdev_deferred_process().

Fix this by converting the notification chain to a raw notification
chain in a similar fashion to the netdev notification chain. Protect
the chain using the RTNL mutex by acquiring it when modifying the chain.
Events are always informed under the RTNL mutex, but add an assertion in
call_switchdev_blocking_notifiers() to make sure this is not violated in
the future.

Maintain the "blocking" prefix as events are always emitted from process
context and listeners are allowed to block.

[1]:
WARNING: possible recursive locking detected
6.14.0-rc4-custom-g079270089484 #1 Not tainted
--------------------------------------------
ip/52731 is trying to acquire lock:
ffffffff850918d8 ((switchdev_blocking_notif_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x58/0xa0

but task is already holding lock:
ffffffff850918d8 ((switchdev_blocking_notif_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x58/0xa0

other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock((switchdev_blocking_notif_chain).rwsem);
lock((switchdev_blocking_notif_chain).rwsem);

*** DEADLOCK ***
May be due to missing lock nesting notation
3 locks held by ip/52731:
 #0: ffffffff84f795b0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x727/0x1dc0
 #1: ffffffff8731f628 (&net->rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x790/0x1dc0
 #2: ffffffff850918d8 ((switchdev_blocking_notif_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x58/0xa0

stack backtrace:
...
? __pfx_down_read+0x10/0x10
? __pfx_mark_lock+0x10/0x10
? __pfx_switchdev_port_attr_set_deferred+0x10/0x10
blocking_notifier_call_chain+0x58/0xa0
switchdev_port_attr_notify.constprop.0+0xb3/0x1b0
? __pfx_switchdev_port_attr_notify.constprop.0+0x10/0x10
? mark_held_locks+0x94/0xe0
? switchdev_deferred_process+0x11a/0x340
switchdev_port_attr_set_deferred+0x27/0xd0
switchdev_deferred_process+0x164/0x340
br_switchdev_port_unoffload+0xc8/0x100 [bridge]
br_switchdev_blocking_event+0x29f/0x580 [bridge]
notifier_call_chain+0xa2/0x440
blocking_notifier_call_chain+0x6e/0xa0
switchdev_bridge_port_unoffload+0xde/0x1a0
...

Fixes: f7a70d6 ("net: bridge: switchdev: Ensure deferred event delivery on unoffload")
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://patch.msgid.link/20250305121509.631207-1-amcohen@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
boryas pushed a commit that referenced this pull request Apr 3, 2025
We were still using the trans after the unlock, leading to this bug in
the retry path:

00255 ------------[ cut here ]------------
00255 kernel BUG at fs/bcachefs/btree_iter.c:3348!
00255 Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
00255 bcachefs (0ca38fe8-0a26-41f9-9b5d-6a27796c7803): /fiotest offset 86048768: no device to read from:
00255   u64s 8 type extent 4098:168192:U32_MAX len 128 ver 0: durability: 0 crc: c_size 128 size 128 offset 0 nonce 0 csum crc32c 0:8040a368  compress none ec: idx 83 block 1 ptr: 0:302:128 gen 0
00255 bcachefs (0ca38fe8-0a26-41f9-9b5d-6a27796c7803): /fiotest offset 85983232: no device to read from:
00255   u64s 8 type extent 4098:168064:U32_MAX len 128 ver 0: durability: 0 crc: c_size 128 size 128 offset 0 nonce 0 csum crc32c 0:43311336  compress none ec: idx 83 block 1 ptr: 0:302:0 gen 0
00255 Modules linked in:
00255 CPU: 5 UID: 0 PID: 304 Comm: kworker/u70:2 Not tainted 6.14.0-rc6-ktest-g526aae23d67d #16040
00255 Hardware name: linux,dummy-virt (DT)
00255 Workqueue: events_unbound bch2_rbio_retry
00255 pstate: 60001005 (nZCv daif -PAN -UAO -TCO -DIT +SSBS BTYPE=--)
00255 pc : __bch2_trans_get+0x100/0x378
00255 lr : __bch2_trans_get+0xa0/0x378
00255 sp : ffffff80c865b760
00255 x29: ffffff80c865b760 x28: 0000000000000000 x27: ffffff80d76ed880
00255 x26: 0000000000000018 x25: 0000000000000000 x24: ffffff80f4ec3760
00255 x23: ffffff80f4010140 x22: 0000000000000056 x21: ffffff80f4ec0000
00255 x20: ffffff80f4ec3788 x19: ffffff80d75f8000 x18: 00000000ffffffff
00255 x17: 2065707974203820 x16: 7334367520200a3a x15: 0000000000000008
00255 x14: 0000000000000001 x13: 0000000000000100 x12: 0000000000000006
00255 x11: ffffffc080b47a40 x10: 0000000000000000 x9 : ffffffc08038dea8
00255 x8 : ffffff80d75fc018 x7 : 0000000000000000 x6 : 0000000000003788
00255 x5 : 0000000000003760 x4 : ffffff80c922de80 x3 : ffffff80f18f0000
00255 x2 : ffffff80c922de80 x1 : 0000000000000130 x0 : 0000000000000006
00255 Call trace:
00255  __bch2_trans_get+0x100/0x378 (P)
00255  bch2_read_io_err+0x98/0x260
00255  bch2_read_endio+0xb8/0x2d0
00255  __bch2_read_extent+0xce8/0xfe0
00255  __bch2_read+0x2a8/0x978
00255  bch2_rbio_retry+0x188/0x318
00255  process_one_work+0x154/0x390
00255  worker_thread+0x20c/0x3b8
00255  kthread+0xf0/0x1b0
00255  ret_from_fork+0x10/0x20
00255 Code: 6b01001f 54ffff01 79408460 3617fec0 (d4210000)
00255 ---[ end trace 0000000000000000 ]---
00255 Kernel panic - not syncing: Oops - BUG: Fatal exception
00255 SMP: stopping secondary CPUs
00255 Kernel Offset: disabled
00255 CPU features: 0x000,00000070,00000010,8240500b
00255 Memory Limit: none
00255 ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]---

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
boryas pushed a commit that referenced this pull request Apr 3, 2025
When removing LAG device from bridge, NETDEV_CHANGEUPPER event is
triggered. Driver finds the lower devices (PFs) to flush all the
offloaded entries. And mlx5_lag_is_shared_fdb is checked, it returns
false if one of PF is unloaded. In such case,
mlx5_esw_bridge_lag_rep_get() and its caller return NULL, instead of
the alive PF, and the flush is skipped.

Besides, the bridge fdb entry's lastuse is updated in mlx5 bridge
event handler. But this SWITCHDEV_FDB_ADD_TO_BRIDGE event can be
ignored in this case because the upper interface for bond is deleted,
and the entry will never be aged because lastuse is never updated.

To make things worse, as the entry is alive, mlx5 bridge workqueue
keeps sending that event, which is then handled by kernel bridge
notifier. It causes the following crash when accessing the passed bond
netdev which is already destroyed.

To fix this issue, remove such checks. LAG state is already checked in
commit 15f8f16 ("net/mlx5: Bridge, verify LAG state when adding
bond to bridge"), driver still need to skip offload if LAG becomes
invalid state after initialization.

 Oops: stack segment: 0000 [#1] SMP
 CPU: 3 UID: 0 PID: 23695 Comm: kworker/u40:3 Tainted: G           OE      6.11.0_mlnx #1
 Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
 Workqueue: mlx5_bridge_wq mlx5_esw_bridge_update_work [mlx5_core]
 RIP: 0010:br_switchdev_event+0x2c/0x110 [bridge]
 Code: 44 00 00 48 8b 02 48 f7 00 00 02 00 00 74 69 41 54 55 53 48 83 ec 08 48 8b a8 08 01 00 00 48 85 ed 74 4a 48 83 fe 02 48 89 d3 <4c> 8b 65 00 74 23 76 49 48 83 fe 05 74 7e 48 83 fe 06 75 2f 0f b7
 RSP: 0018:ffffc900092cfda0 EFLAGS: 00010297
 RAX: ffff888123bfe000 RBX: ffffc900092cfe08 RCX: 00000000ffffffff
 RDX: ffffc900092cfe08 RSI: 0000000000000001 RDI: ffffffffa0c585f0
 RBP: 6669746f6e690a30 R08: 0000000000000000 R09: ffff888123ae92c8
 R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888123ae9c60
 R13: 0000000000000001 R14: ffffc900092cfe08 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f15914c8734 CR3: 0000000002830005 CR4: 0000000000770ef0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? __die_body+0x1a/0x60
  ? die+0x38/0x60
  ? do_trap+0x10b/0x120
  ? do_error_trap+0x64/0xa0
  ? exc_stack_segment+0x33/0x50
  ? asm_exc_stack_segment+0x22/0x30
  ? br_switchdev_event+0x2c/0x110 [bridge]
  ? sched_balance_newidle.isra.149+0x248/0x390
  notifier_call_chain+0x4b/0xa0
  atomic_notifier_call_chain+0x16/0x20
  mlx5_esw_bridge_update+0xec/0x170 [mlx5_core]
  mlx5_esw_bridge_update_work+0x19/0x40 [mlx5_core]
  process_scheduled_works+0x81/0x390
  worker_thread+0x106/0x250
  ? bh_worker+0x110/0x110
  kthread+0xb7/0xe0
  ? kthread_park+0x80/0x80
  ret_from_fork+0x2d/0x50
  ? kthread_park+0x80/0x80
  ret_from_fork_asm+0x11/0x20
  </TASK>

Fixes: ff9b752 ("net/mlx5: Bridge, support LAG")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/1741644104-97767-6-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
boryas pushed a commit that referenced this pull request Apr 3, 2025
When on a MANA VM hibernation is triggered, as part of hibernate_snapshot(),
mana_gd_suspend() and mana_gd_resume() are called. If during this
mana_gd_resume(), a failure occurs with HWC creation, mana_port_debugfs
pointer does not get reinitialized and ends up pointing to older,
cleaned-up dentry.
Further in the hibernation path, as part of power_down(), mana_gd_shutdown()
is triggered. This call, unaware of the failures in resume, tries to cleanup
the already cleaned up  mana_port_debugfs value and hits the following bug:

[  191.359296] mana 7870:00:00.0: Shutdown was called
[  191.359918] BUG: kernel NULL pointer dereference, address: 0000000000000098
[  191.360584] #PF: supervisor write access in kernel mode
[  191.361125] #PF: error_code(0x0002) - not-present page
[  191.361727] PGD 1080ea067 P4D 0
[  191.362172] Oops: Oops: 0002 [#1] SMP NOPTI
[  191.362606] CPU: 11 UID: 0 PID: 1674 Comm: bash Not tainted 6.14.0-rc5+ #2
[  191.363292] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024
[  191.364124] RIP: 0010:down_write+0x19/0x50
[  191.364537] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 de cd ff ff 31 c0 ba 01 00 00 00 <f0> 48 0f b1 13 75 16 65 48 8b 05 88 24 4c 6a 48 89 43 08 48 8b 5d
[  191.365867] RSP: 0000:ff45fbe0c1c037b8 EFLAGS: 00010246
[  191.366350] RAX: 0000000000000000 RBX: 0000000000000098 RCX: ffffff8100000000
[  191.366951] RDX: 0000000000000001 RSI: 0000000000000064 RDI: 0000000000000098
[  191.367600] RBP: ff45fbe0c1c037c0 R08: 0000000000000000 R09: 0000000000000001
[  191.368225] R10: ff45fbe0d2b01000 R11: 0000000000000008 R12: 0000000000000000
[  191.368874] R13: 000000000000000b R14: ff43dc27509d67c0 R15: 0000000000000020
[  191.369549] FS:  00007dbc5001e740(0000) GS:ff43dc663f380000(0000) knlGS:0000000000000000
[  191.370213] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  191.370830] CR2: 0000000000000098 CR3: 0000000168e8e002 CR4: 0000000000b73ef0
[  191.371557] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  191.372192] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[  191.372906] Call Trace:
[  191.373262]  <TASK>
[  191.373621]  ? show_regs+0x64/0x70
[  191.374040]  ? __die+0x24/0x70
[  191.374468]  ? page_fault_oops+0x290/0x5b0
[  191.374875]  ? do_user_addr_fault+0x448/0x800
[  191.375357]  ? exc_page_fault+0x7a/0x160
[  191.375971]  ? asm_exc_page_fault+0x27/0x30
[  191.376416]  ? down_write+0x19/0x50
[  191.376832]  ? down_write+0x12/0x50
[  191.377232]  simple_recursive_removal+0x4a/0x2a0
[  191.377679]  ? __pfx_remove_one+0x10/0x10
[  191.378088]  debugfs_remove+0x44/0x70
[  191.378530]  mana_detach+0x17c/0x4f0
[  191.378950]  ? __flush_work+0x1e2/0x3b0
[  191.379362]  ? __cond_resched+0x1a/0x50
[  191.379787]  mana_remove+0xf2/0x1a0
[  191.380193]  mana_gd_shutdown+0x3b/0x70
[  191.380642]  pci_device_shutdown+0x3a/0x80
[  191.381063]  device_shutdown+0x13e/0x230
[  191.381480]  kernel_power_off+0x35/0x80
[  191.381890]  hibernate+0x3c6/0x470
[  191.382312]  state_store+0xcb/0xd0
[  191.382734]  kobj_attr_store+0x12/0x30
[  191.383211]  sysfs_kf_write+0x3e/0x50
[  191.383640]  kernfs_fop_write_iter+0x140/0x1d0
[  191.384106]  vfs_write+0x271/0x440
[  191.384521]  ksys_write+0x72/0xf0
[  191.384924]  __x64_sys_write+0x19/0x20
[  191.385313]  x64_sys_call+0x2b0/0x20b0
[  191.385736]  do_syscall_64+0x79/0x150
[  191.386146]  ? __mod_memcg_lruvec_state+0xe7/0x240
[  191.386676]  ? __lruvec_stat_mod_folio+0x79/0xb0
[  191.387124]  ? __pfx_lru_add+0x10/0x10
[  191.387515]  ? queued_spin_unlock+0x9/0x10
[  191.387937]  ? do_anonymous_page+0x33c/0xa00
[  191.388374]  ? __handle_mm_fault+0xcf3/0x1210
[  191.388805]  ? __count_memcg_events+0xbe/0x180
[  191.389235]  ? handle_mm_fault+0xae/0x300
[  191.389588]  ? do_user_addr_fault+0x559/0x800
[  191.390027]  ? irqentry_exit_to_user_mode+0x43/0x230
[  191.390525]  ? irqentry_exit+0x1d/0x30
[  191.390879]  ? exc_page_fault+0x86/0x160
[  191.391235]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  191.391745] RIP: 0033:0x7dbc4ff1c574
[  191.392111] 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 d5 ea 0e 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
[  191.393412] RSP: 002b:00007ffd95a23ab8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[  191.393990] RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007dbc4ff1c574
[  191.394594] RDX: 0000000000000005 RSI: 00005a6eeadb0ce0 RDI: 0000000000000001
[  191.395215] RBP: 00007ffd95a23ae0 R08: 00007dbc50003b20 R09: 0000000000000000
[  191.395805] R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000000005
[  191.396404] R13: 00005a6eeadb0ce0 R14: 00007dbc500045c0 R15: 00007dbc50001ee0
[  191.396987]  </TASK>

To fix this, we explicitly set such mana debugfs variables to NULL after
debugfs_remove() is called.

Fixes: 6607c17 ("net: mana: Enable debugfs files for MANA device")
Cc: stable@vger.kernel.org
Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Link: https://patch.msgid.link/1741688260-28922-1-git-send-email-shradhagupta@linux.microsoft.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
boryas pushed a commit that referenced this pull request May 21, 2025
A vmemmap altmap is a device-provided region used to provide
backing storage for struct pages. For each namespace, the altmap
should belong to that same namespace. If the namespaces are
created unaligned, there is a chance that the section vmemmap
start address could also be unaligned. If the section vmemmap
start address is unaligned, the altmap page allocated from the
current namespace might be used by the previous namespace also.
During the free operation, since the altmap is shared between two
namespaces, the previous namespace may detect that the page does
not belong to its altmap and incorrectly assume that the page is a
normal page. It then attempts to free the normal page, which leads
to a kernel crash.

Kernel attempted to read user page (18) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on read at 0x00000018
Faulting instruction address: 0xc000000000530c7c
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
CPU: 32 PID: 2104 Comm: ndctl Kdump: loaded Tainted: G        W
NIP:  c000000000530c7c LR: c000000000530e00 CTR: 0000000000007ffe
REGS: c000000015e57040 TRAP: 0300   Tainted: G        W
MSR:  800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 84482404
CFAR: c000000000530dfc DAR: 0000000000000018 DSISR: 40000000 IRQMASK: 0
GPR00: c000000000530e00 c000000015e572e0 c000000002c5cb00 c00c000101008040
GPR04: 0000000000000000 0000000000000007 0000000000000001 000000000000001f
GPR08: 0000000000000005 0000000000000000 0000000000000018 0000000000002000
GPR12: c0000000001d2fb0 c0000060de6b0080 0000000000000000 c0000060dbf90020
GPR16: c00c000101008000 0000000000000001 0000000000000000 c000000125b20f00
GPR20: 0000000000000001 0000000000000000 ffffffffffffffff c00c000101007fff
GPR24: 0000000000000001 0000000000000000 0000000000000000 0000000000000000
GPR28: 0000000004040201 0000000000000001 0000000000000000 c00c000101008040
NIP [c000000000530c7c] get_pfnblock_flags_mask+0x7c/0xd0
LR [c000000000530e00] free_unref_page_prepare+0x130/0x4f0
Call Trace:
free_unref_page+0x50/0x1e0
free_reserved_page+0x40/0x68
free_vmemmap_pages+0x98/0xe0
remove_pte_table+0x164/0x1e8
remove_pmd_table+0x204/0x2c8
remove_pud_table+0x1c4/0x288
remove_pagetable+0x1c8/0x310
vmemmap_free+0x24/0x50
section_deactivate+0x28c/0x2a0
__remove_pages+0x84/0x110
arch_remove_memory+0x38/0x60
memunmap_pages+0x18c/0x3d0
devm_action_release+0x30/0x50
release_nodes+0x68/0x140
devres_release_group+0x100/0x190
dax_pmem_compat_release+0x44/0x80 [dax_pmem_compat]
device_for_each_child+0x8c/0x100
[dax_pmem_compat_remove+0x2c/0x50 [dax_pmem_compat]
nvdimm_bus_remove+0x78/0x140 [libnvdimm]
device_remove+0x70/0xd0

Another issue is that if there is no altmap, a PMD-sized vmemmap
page will be allocated from RAM, regardless of the alignment of
the section start address. If the section start address is not
aligned to the PMD size, a VM_BUG_ON will be triggered when
setting the PMD-sized page to page table.

In this patch, we are aligning the section vmemmap start address
to PAGE_SIZE. After alignment, the start address will not be
part of the current namespace, and a normal page will be allocated
for the vmemmap mapping of the current section. For the remaining
sections, altmaps will be allocated. During the free operation,
the normal page will be correctly freed.

In the same way, a PMD_SIZE vmemmap page will be allocated only if
the section start address is PMD_SIZE-aligned; otherwise, it will
fall back to a PAGE-sized vmemmap allocation.

Without this patch
==================
NS1 start               NS2 start
 _________________________________________________________
|         NS1               |            NS2              |
 ---------------------------------------------------------
| Altmap| Altmap | .....|Altmap| Altmap | ...........
|  NS1  |  NS1   |      | NS2  |  NS2   |

In the above scenario, NS1 and NS2 are two namespaces. The vmemmap
for NS1 comes from Altmap NS1, which belongs to NS1, and the
vmemmap for NS2 comes from Altmap NS2, which belongs to NS2.

The vmemmap start for NS2 is not aligned, so Altmap NS2 is shared
by both NS1 and NS2. During the free operation in NS1, Altmap NS2
is not part of NS1's altmap, causing it to attempt to free an
invalid page.

With this patch
===============
NS1 start               NS2 start
 _________________________________________________________
|         NS1               |            NS2              |
 ---------------------------------------------------------
| Altmap| Altmap | .....| Normal | Altmap | Altmap |.......
|  NS1  |  NS1   |      |  Page  |  NS2   |  NS2   |

If the vmemmap start for NS2 is not aligned then we are allocating
a normal page. NS1 and NS2 vmemmap will be freed correctly.

Fixes: 368a059 ("powerpc/book3s64/vmemmap: switch radix to use a different vmemmap handling function")
Co-developed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Donet Tom <donettom@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/8f98ec2b442977c618f7256cec88eb17dde3f2b9.1741609795.git.donettom@linux.ibm.com
boryas pushed a commit that referenced this pull request May 21, 2025
for_each_present_section_nr() was introduced to add_boot_memory_block()
by commit 61659ef ("drivers/base/memory: improve add_boot_memory_block()").
It causes unnecessary overhead when the present sections are really
sparse. next_present_section_nr() called by the macro to find the next
present section, which is far away from the spanning sections in the
specified block. Too much time consumed by next_present_section_nr()
in this case, which can lead to softlockup as observed by Aditya Gupta
on IBM Power10 machine.

  watchdog: BUG: soft lockup - CPU#248 stuck for 22s! [swapper/248:1]
  Modules linked in:
  CPU: 248 UID: 0 PID: 1 Comm: swapper/248 Not tainted 6.15.0-rc1-next-20250408 #1 VOLUNTARY
  Hardware name: 9105-22A POWER10 (raw) 0x800200 opal:v7.1-107-gfda75d121942 PowerNV
  NIP:  c00000000209218c LR: c000000002092204 CTR: 0000000000000000
  REGS: c00040000418fa30 TRAP: 0900   Not tainted  (6.15.0-rc1-next-20250408)
  MSR:  9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE>  CR: 28000428  XER: 00000000
  CFAR: 0000000000000000 IRQMASK: 0
  GPR00: c000000002092204 c00040000418fcd0 c000000001b08100 0000000000000040
  GPR04: 0000000000013e00 c000c03ffebabb00 0000000000c03fff c000400fff587f80
  GPR08: 0000000000000000 00000000001196f7 0000000000000000 0000000028000428
  GPR12: 0000000000000000 c000000002e80000 c00000000001007c 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR28: c000000002df7f70 0000000000013dc0 c0000000011dd898 0000000008000000
  NIP [c00000000209218c] memory_dev_init+0x114/0x1e0
  LR [c000000002092204] memory_dev_init+0x18c/0x1e0
  Call Trace:
  [c00040000418fcd0] [c000000002092204] memory_dev_init+0x18c/0x1e0 (unreliable)
  [c00040000418fd50] [c000000002091348] driver_init+0x78/0xa4
  [c00040000418fd70] [c0000000020063ac] kernel_init_freeable+0x22c/0x370
  [c00040000418fde0] [c0000000000100a8] kernel_init+0x34/0x25c
  [c00040000418fe50] [c00000000000cd94] ret_from_kernel_user_thread+0x14/0x1c

Avoid the overhead by folding for_each_present_section_nr() to the outer
loop. add_boot_memory_block() is dropped after that.

Fixes: 61659ef ("drivers/base/memory: improve add_boot_memory_block()")
Closes: https://lore.kernel.org/linux-mm/20250409180344.477916-1-adityag@linux.ibm.com
Reported-by: Aditya Gupta <adityag@linux.ibm.com>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Aditya Gupta <adityag@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250410125110.1232329-1-gshan@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
boryas pushed a commit that referenced this pull request May 21, 2025
There was a bug report about a NULL pointer dereference in
__btrfs_add_free_space_zoned() that ultimately happens because a
conversion from the default metadata profile DUP to a RAID1 profile on two
disks.

The stack trace has the following signature:

  BTRFS error (device sdc): zoned: write pointer offset mismatch of zones in raid1 profile
  BUG: kernel NULL pointer dereference, address: 0000000000000058
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
  RIP: 0010:__btrfs_add_free_space_zoned.isra.0+0x61/0x1a0
  RSP: 0018:ffffa236b6f3f6d0 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff96c8132f3400 RCX: 0000000000000001
  RDX: 0000000010000000 RSI: 0000000000000000 RDI: ffff96c8132f3410
  RBP: 0000000010000000 R08: 0000000000000003 R09: 0000000000000000
  R10: 0000000000000000 R11: 00000000ffffffff R12: 0000000000000000
  R13: ffff96c758f65a40 R14: 0000000000000001 R15: 000011aac0000000
  FS: 00007fdab1cb2900(0000) GS:ffff96e60ca00000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000058 CR3: 00000001a05ae000 CR4: 0000000000350ef0
  Call Trace:
  <TASK>
  ? __die_body.cold+0x19/0x27
  ? page_fault_oops+0x15c/0x2f0
  ? exc_page_fault+0x7e/0x180
  ? asm_exc_page_fault+0x26/0x30
  ? __btrfs_add_free_space_zoned.isra.0+0x61/0x1a0
  btrfs_add_free_space_async_trimmed+0x34/0x40
  btrfs_add_new_free_space+0x107/0x120
  btrfs_make_block_group+0x104/0x2b0
  btrfs_create_chunk+0x977/0xf20
  btrfs_chunk_alloc+0x174/0x510
  ? srso_return_thunk+0x5/0x5f
  btrfs_inc_block_group_ro+0x1b1/0x230
  btrfs_relocate_block_group+0x9e/0x410
  btrfs_relocate_chunk+0x3f/0x130
  btrfs_balance+0x8ac/0x12b0
  ? srso_return_thunk+0x5/0x5f
  ? srso_return_thunk+0x5/0x5f
  ? __kmalloc_cache_noprof+0x14c/0x3e0
  btrfs_ioctl+0x2686/0x2a80
  ? srso_return_thunk+0x5/0x5f
  ? ioctl_has_perm.constprop.0.isra.0+0xd2/0x120
  __x64_sys_ioctl+0x97/0xc0
  do_syscall_64+0x82/0x160
  ? srso_return_thunk+0x5/0x5f
  ? __memcg_slab_free_hook+0x11a/0x170
  ? srso_return_thunk+0x5/0x5f
  ? kmem_cache_free+0x3f0/0x450
  ? srso_return_thunk+0x5/0x5f
  ? srso_return_thunk+0x5/0x5f
  ? syscall_exit_to_user_mode+0x10/0x210
  ? srso_return_thunk+0x5/0x5f
  ? do_syscall_64+0x8e/0x160
  ? sysfs_emit+0xaf/0xc0
  ? srso_return_thunk+0x5/0x5f
  ? srso_return_thunk+0x5/0x5f
  ? seq_read_iter+0x207/0x460
  ? srso_return_thunk+0x5/0x5f
  ? vfs_read+0x29c/0x370
  ? srso_return_thunk+0x5/0x5f
  ? srso_return_thunk+0x5/0x5f
  ? syscall_exit_to_user_mode+0x10/0x210
  ? srso_return_thunk+0x5/0x5f
  ? do_syscall_64+0x8e/0x160
  ? srso_return_thunk+0x5/0x5f
  ? exc_page_fault+0x7e/0x180
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7fdab1e0ca6d
  RSP: 002b:00007ffeb2b60c80 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fdab1e0ca6d
  RDX: 00007ffeb2b60d80 RSI: 00000000c4009420 RDI: 0000000000000003
  RBP: 00007ffeb2b60cd0 R08: 0000000000000000 R09: 0000000000000013
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffeb2b6343b R14: 00007ffeb2b60d80 R15: 0000000000000001
  </TASK>
  CR2: 0000000000000058
  ---[ end trace 0000000000000000 ]---

The 1st line is the most interesting here:

 BTRFS error (device sdc): zoned: write pointer offset mismatch of zones in raid1 profile

When a RAID1 block-group is created and a write pointer mismatch between
the disks in the RAID set is detected, btrfs sets the alloc_offset to the
length of the block group marking it as full. Afterwards the code expects
that a balance operation will evacuate the data in this block-group and
repair the problems.

But before this is possible, the new space of this block-group will be
accounted in the free space cache. But in __btrfs_add_free_space_zoned()
it is being checked if it is a initial creation of a block group and if
not a reclaim decision will be made. But the decision if a block-group's
free space accounting is done for an initial creation depends on if the
size of the added free space is the whole length of the block-group and
the allocation offset is 0.

But as btrfs_load_block_group_zone_info() sets the allocation offset to
the zone capacity (i.e. marking the block-group as full) this initial
decision is not met, and the space_info pointer in the 'struct
btrfs_block_group' has not yet been assigned.

Fail creation of the block group and rely on manual user intervention to
re-balance the filesystem.

Afterwards the filesystem can be unmounted, mounted in degraded mode and
the missing device can be removed after a full balance of the filesystem.

Reported-by: 西木野羰基 <yanqiyu01@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CAB_b4sBhDe3tscz=duVyhc9hNE+gu=B8CrgLO152uMyanR8BEA@mail.gmail.com/
Fixes: b1934cd ("btrfs: zoned: handle broken write pointer on zones")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
boryas pushed a commit that referenced this pull request May 21, 2025
If we have a failure at create_reloc_inode(), under the 'out' label we
assign an error pointer to the 'inode' variable and then return a weird
pointer because we return the expression "&inode->vfs_inode":

   static noinline_for_stack struct inode *create_reloc_inode(
                                    const struct btrfs_block_group *group)
   {
       (...)
   out:
       (...)
       if (ret) {
            if (inode)
                  iput(&inode->vfs_inode);
            inode = ERR_PTR(ret);
       }
       return &inode->vfs_inode;
   }

This can make us return a pointer that is not an error pointer and make
the caller proceed as if an error didn't happen and later result in an
invalid memory access when dereferencing the inode pointer.
Syzbot reported reported such a case with the following stack trace:

   R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
   R13: 0000000000000000 R14: 431bde82d7b634db R15: 00007ffc55de5790
    </TASK>
   BTRFS info (device loop0): relocating block group 6881280 flags data|metadata
   Oops: general protection fault, probably for non-canonical address 0xdffffc0000000045: 0000 [#1] SMP KASAN NOPTI
   KASAN: null-ptr-deref in range [0x0000000000000228-0x000000000000022f]
   CPU: 0 UID: 0 PID: 5332 Comm: syz-executor215 Not tainted 6.14.0-syzkaller-13423-ga8662bcd2ff1 #0 PREEMPT(full)
   Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
   RIP: 0010:relocate_file_extent_cluster+0xe7/0x1750 fs/btrfs/relocation.c:2971
   Code: 00 74 08 (...)
   RSP: 0018:ffffc9000d3375e0 EFLAGS: 00010203
   RAX: 0000000000000045 RBX: 000000000000022c RCX: ffff888000562440
   RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880452db000
   RBP: ffffc9000d337870 R08: ffffffff84089251 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
   R13: ffffffff9368a020 R14: 0000000000000394 R15: ffff8880452db000
   FS:  000055558bc7b380(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 000055a7a192e740 CR3: 0000000036e2e000 CR4: 0000000000352ef0
   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
   Call Trace:
    <TASK>
    relocate_block_group+0xa1e/0xd50 fs/btrfs/relocation.c:3657
    btrfs_relocate_block_group+0x777/0xd80 fs/btrfs/relocation.c:4011
    btrfs_relocate_chunk+0x12c/0x3b0 fs/btrfs/volumes.c:3511
    __btrfs_balance+0x1a93/0x25e0 fs/btrfs/volumes.c:4292
    btrfs_balance+0xbde/0x10c0 fs/btrfs/volumes.c:4669
    btrfs_ioctl_balance+0x3f5/0x660 fs/btrfs/ioctl.c:3586
    vfs_ioctl fs/ioctl.c:51 [inline]
    __do_sys_ioctl fs/ioctl.c:906 [inline]
    __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:892
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f
   RIP: 0033:0x7fb4ef537dd9
   Code: 28 00 00 (...)
   RSP: 002b:00007ffc55de5728 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
   RAX: ffffffffffffffda RBX: 00007ffc55de5750 RCX: 00007fb4ef537dd9
   RDX: 0000200000000440 RSI: 00000000c4009420 RDI: 0000000000000003
   RBP: 0000000000000002 R08: 00007ffc55de54c6 R09: 00007ffc55de5770
   R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
   R13: 0000000000000000 R14: 431bde82d7b634db R15: 00007ffc55de5790
    </TASK>
   Modules linked in:
   ---[ end trace 0000000000000000 ]---
   RIP: 0010:relocate_file_extent_cluster+0xe7/0x1750 fs/btrfs/relocation.c:2971
   Code: 00 74 08 (...)
   RSP: 0018:ffffc9000d3375e0 EFLAGS: 00010203
   RAX: 0000000000000045 RBX: 000000000000022c RCX: ffff888000562440
   RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880452db000
   RBP: ffffc9000d337870 R08: ffffffff84089251 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
   R13: ffffffff9368a020 R14: 0000000000000394 R15: ffff8880452db000
   FS:  000055558bc7b380(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000
   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   CR2: 000055a7a192e740 CR3: 0000000036e2e000 CR4: 0000000000352ef0
   DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
   DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
   ----------------
   Code disassembly (best guess):
      0:	00 74 08 48          	add    %dh,0x48(%rax,%rcx,1)
      4:	89 df                	mov    %ebx,%edi
      6:	e8 f8 36 24 fe       	call   0xfe243703
      b:	48 89 9c 24 30 01 00 	mov    %rbx,0x130(%rsp)
     12:	00
     13:	4c 89 74 24 28       	mov    %r14,0x28(%rsp)
     18:	4d 8b 76 10          	mov    0x10(%r14),%r14
     1c:	49 8d 9e 98 fe ff ff 	lea    -0x168(%r14),%rbx
     23:	48 89 d8             	mov    %rbx,%rax
     26:	48 c1 e8 03          	shr    $0x3,%rax
   * 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
     2f:	74 08                	je     0x39
     31:	48 89 df             	mov    %rbx,%rdi
     34:	e8 ca 36 24 fe       	call   0xfe243703
     39:	4c 8b 3b             	mov    (%rbx),%r15
     3c:	48                   	rex.W
     3d:	8b                   	.byte 0x8b
     3e:	44                   	rex.R
     3f:	24                   	.byte 0x24

So fix this by returning the error immediately.

Reported-by: syzbot+7481815bb47ef3e702e2@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/67f14ee9.050a0220.0a13.023e.GAE@google.com/
Fixes: b204e5c ("btrfs: make btrfs_iget() return a btrfs inode instead")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
boryas pushed a commit that referenced this pull request May 21, 2025
There is a potential deadlock if we do report zones in an IO context, detailed
in below lockdep report. When one process do a report zones and another process
freezes the block device, the report zones side cannot allocate a tag because
the freeze is already started. This can thus result in new block group creation
to hang forever, blocking the write path.

Thankfully, a new block group should be created on empty zones. So, reporting
the zones is not necessary and we can set the write pointer = 0 and load the
zone capacity from the block layer using bdev_zone_capacity() helper.

 ======================================================
 WARNING: possible circular locking dependency detected
 6.14.0-rc1 torvalds#252 Not tainted
 ------------------------------------------------------
 modprobe/1110 is trying to acquire lock:
 ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60

 but task is already holding lock:
 ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #3 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}:
        blk_queue_enter+0x3d9/0x500
        blk_mq_alloc_request+0x47d/0x8e0
        scsi_execute_cmd+0x14f/0xb80
        sd_zbc_do_report_zones+0x1c1/0x470
        sd_zbc_report_zones+0x362/0xd60
        blkdev_report_zones+0x1b1/0x2e0
        btrfs_get_dev_zones+0x215/0x7e0 [btrfs]
        btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs]
        btrfs_make_block_group+0x36b/0x870 [btrfs]
        btrfs_create_chunk+0x147d/0x2320 [btrfs]
        btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs]
        start_transaction+0xce6/0x1620 [btrfs]
        btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs]
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #2 (&fs_info->dev_replace.rwsem){++++}-{4:4}:
        down_read+0x9b/0x470
        btrfs_map_block+0x2ce/0x2ce0 [btrfs]
        btrfs_submit_chunk+0x2d4/0x16c0 [btrfs]
        btrfs_submit_bbio+0x16/0x30 [btrfs]
        btree_write_cache_pages+0xb5a/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}:
        __mutex_lock+0x1aa/0x1360
        btree_write_cache_pages+0x252/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}:
        __lock_acquire+0x2f52/0x5ea0
        lock_acquire+0x1b1/0x540
        __flush_work+0x3ac/0xb60
        wb_shutdown+0x15b/0x1f0
        bdi_unregister+0x172/0x5b0
        del_gendisk+0x841/0xa20
        sd_remove+0x85/0x130
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        __scsi_remove_device+0x272/0x340
        scsi_forget_host+0xf7/0x170
        scsi_remove_host+0xd2/0x2a0
        sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        device_unregister+0x13/0xa0
        sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
        scsi_debug_exit+0x17/0x70 [scsi_debug]
        __do_sys_delete_module.isra.0+0x321/0x520
        do_syscall_64+0x93/0x180
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)torvalds#16

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&q->q_usage_counter(queue)torvalds#16);
                                lock(&fs_info->dev_replace.rwsem);
                                lock(&q->q_usage_counter(queue)torvalds#16);
   lock((work_completion)(&(&wb->dwork)->work));

  *** DEADLOCK ***

 5 locks held by modprobe/1110:
  #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  #1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0
  #2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  #3: ffff8881205b6f20 (&q->q_usage_counter(queue)torvalds#16){++++}-{0:0}, at: sd_remove+0x85/0x130
  #4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60

 stack backtrace:
 CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 torvalds#252
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6a/0x90
  print_circular_bug.cold+0x1e0/0x274
  check_noncircular+0x306/0x3f0
  ? __pfx_check_noncircular+0x10/0x10
  ? mark_lock+0xf5/0x1650
  ? __pfx_check_irq_usage+0x10/0x10
  ? lockdep_lock+0xca/0x1c0
  ? __pfx_lockdep_lock+0x10/0x10
  __lock_acquire+0x2f52/0x5ea0
  ? __pfx___lock_acquire+0x10/0x10
  ? __pfx_mark_lock+0x10/0x10
  lock_acquire+0x1b1/0x540
  ? __flush_work+0x38f/0xb60
  ? __pfx_lock_acquire+0x10/0x10
  ? __pfx_lock_release+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  ? __flush_work+0x38f/0xb60
  __flush_work+0x3ac/0xb60
  ? __flush_work+0x38f/0xb60
  ? __pfx_mark_lock+0x10/0x10
  ? __pfx___flush_work+0x10/0x10
  ? __pfx_wq_barrier_func+0x10/0x10
  ? __pfx___might_resched+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  wb_shutdown+0x15b/0x1f0
  bdi_unregister+0x172/0x5b0
  ? __pfx_bdi_unregister+0x10/0x10
  ? up_write+0x1ba/0x510
  del_gendisk+0x841/0xa20
  ? __pfx_del_gendisk+0x10/0x10
  ? _raw_spin_unlock_irqrestore+0x35/0x60
  ? __pm_runtime_resume+0x79/0x110
  sd_remove+0x85/0x130
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  __scsi_remove_device+0x272/0x340
  scsi_forget_host+0xf7/0x170
  scsi_remove_host+0xd2/0x2a0
  sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
  ? kernfs_remove_by_name_ns+0xc0/0xf0
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  ? __pfx___mutex_unlock_slowpath+0x10/0x10
  device_unregister+0x13/0xa0
  sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
  scsi_debug_exit+0x17/0x70 [scsi_debug]
  __do_sys_delete_module.isra.0+0x321/0x520
  ? __pfx___do_sys_delete_module.isra.0+0x10/0x10
  ? __pfx_slab_free_after_rcu_debug+0x10/0x10
  ? kasan_save_stack+0x2c/0x50
  ? kasan_record_aux_stack+0xa3/0xb0
  ? __call_rcu_common.constprop.0+0xc4/0xfb0
  ? kmem_cache_free+0x3a0/0x590
  ? __x64_sys_close+0x78/0xd0
  do_syscall_64+0x93/0x180
  ? lock_is_held_type+0xd5/0x130
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? lockdep_hardirqs_on+0x78/0x100
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? __pfx___call_rcu_common.constprop.0+0x10/0x10
  ? kmem_cache_free+0x3a0/0x590
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  ? __pfx___x64_sys_openat+0x10/0x10
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7f436712b68b
 RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b
 RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8
 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000
 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000
 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000
  </TASK>

Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
CC: <stable@vger.kernel.org> # 6.13+
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
boryas pushed a commit that referenced this pull request May 21, 2025
It looks like GPUs are used after shutdown is invoked.
Thus, breaking virtio gpu in the shutdown callback is not a good idea -
guest hangs attempting to finish console drawing, with these warnings:

[   20.504464] WARNING: CPU: 0 PID: 568 at drivers/gpu/drm/virtio/virtgpu_vq.c:358 virtio_gpu_queue_ctrl_sgs+0x236/0x290 [virtio_gpu]
[   20.505685] Modules linked in: 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 nfnetlink vfat fat intel_rapl_msr intel_rapl_common intel_uncore_frequency_common nfit libnvdimm kvm_intel kvm rapl iTCO_wdt iTCO_vendor_support virtio_gpu virtio_dma_buf pcspkr drm_shmem_helper i2c_i801 drm_kms_helper lpc_ich i2c_smbus virtio_balloon joydev drm fuse xfs libcrc32c ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata virtio_net ghash_clmulni_intel net_failover virtio_blk failover serio_raw dm_mirror dm_region_hash dm_log dm_mod
[   20.511847] CPU: 0 PID: 568 Comm: kworker/0:3 Kdump: loaded Tainted: G        W         -------  ---  5.14.0-578.6675_1757216455.el9.x86_64 #1
[   20.513157] Hardware name: Red Hat KVM/RHEL, BIOS edk2-20241117-3.el9 11/17/2024
[   20.513918] Workqueue: events drm_fb_helper_damage_work [drm_kms_helper]
[   20.514626] RIP: 0010:virtio_gpu_queue_ctrl_sgs+0x236/0x290 [virtio_gpu]
[   20.515332] Code: 00 00 48 85 c0 74 0c 48 8b 78 08 48 89 ee e8 51 50 00 00 65 ff 0d 42 e3 74 3f 0f 85 69 ff ff ff 0f 1f 44 00 00 e9 5f ff ff ff <0f> 0b e9 3f ff ff ff 48 83 3c 24 00 74 0e 49 8b 7f 40 48 85 ff 74
[   20.517272] RSP: 0018:ff34f0a8c0787ad8 EFLAGS: 00010282
[   20.517820] RAX: 00000000fffffffb RBX: 0000000000000000 RCX: 0000000000000820
[   20.518565] RDX: 0000000000000000 RSI: ff34f0a8c0787be0 RDI: ff218bef03a26300
[   20.519308] RBP: ff218bef03a26300 R08: 0000000000000001 R09: ff218bef07224360
[   20.520059] R10: 0000000000008dc0 R11: 0000000000000002 R12: ff218bef02630028
[   20.520806] R13: ff218bef0263fb48 R14: ff218bef00cb8000 R15: ff218bef07224360
[   20.521555] FS:  0000000000000000(0000) GS:ff218bef7ba00000(0000) knlGS:0000000000000000
[   20.522397] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   20.522996] CR2: 000055ac4f7871c0 CR3: 000000010b9f2002 CR4: 0000000000771ef0
[   20.523740] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   20.524477] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[   20.525223] PKRU: 55555554
[   20.525515] Call Trace:
[   20.525777]  <TASK>
[   20.526003]  ? show_trace_log_lvl+0x1c4/0x2df
[   20.526464]  ? show_trace_log_lvl+0x1c4/0x2df
[   20.526925]  ? virtio_gpu_queue_fenced_ctrl_buffer+0x82/0x2c0 [virtio_gpu]
[   20.527643]  ? virtio_gpu_queue_ctrl_sgs+0x236/0x290 [virtio_gpu]
[   20.528282]  ? __warn+0x7e/0xd0
[   20.528621]  ? virtio_gpu_queue_ctrl_sgs+0x236/0x290 [virtio_gpu]
[   20.529256]  ? report_bug+0x100/0x140
[   20.529643]  ? handle_bug+0x3c/0x70
[   20.530010]  ? exc_invalid_op+0x14/0x70
[   20.530421]  ? asm_exc_invalid_op+0x16/0x20
[   20.530862]  ? virtio_gpu_queue_ctrl_sgs+0x236/0x290 [virtio_gpu]
[   20.531506]  ? virtio_gpu_queue_ctrl_sgs+0x174/0x290 [virtio_gpu]
[   20.532148]  virtio_gpu_queue_fenced_ctrl_buffer+0x82/0x2c0 [virtio_gpu]
[   20.532843]  virtio_gpu_primary_plane_update+0x3e2/0x460 [virtio_gpu]
[   20.533520]  drm_atomic_helper_commit_planes+0x108/0x320 [drm_kms_helper]
[   20.534233]  drm_atomic_helper_commit_tail+0x45/0x80 [drm_kms_helper]
[   20.534914]  commit_tail+0xd2/0x130 [drm_kms_helper]
[   20.535446]  drm_atomic_helper_commit+0x11b/0x140 [drm_kms_helper]
[   20.536097]  drm_atomic_commit+0xa4/0xe0 [drm]
[   20.536588]  ? __pfx___drm_printfn_info+0x10/0x10 [drm]
[   20.537162]  drm_atomic_helper_dirtyfb+0x192/0x270 [drm_kms_helper]
[   20.537823]  drm_fbdev_shmem_helper_fb_dirty+0x43/0xa0 [drm_shmem_helper]
[   20.538536]  drm_fb_helper_damage_work+0x87/0x160 [drm_kms_helper]
[   20.539188]  process_one_work+0x194/0x380
[   20.539612]  worker_thread+0x2fe/0x410
[   20.540007]  ? __pfx_worker_thread+0x10/0x10
[   20.540456]  kthread+0xdd/0x100
[   20.540791]  ? __pfx_kthread+0x10/0x10
[   20.541190]  ret_from_fork+0x29/0x50
[   20.541566]  </TASK>
[   20.541802] ---[ end trace 0000000000000000 ]---

It looks like the shutdown is called in the middle of console drawing, so
we should either wait for it to finish, or let drm handle the shutdown.

This patch implements this second option:

Add an option for drivers to bypass the common break+reset handling.
As DRM is careful to flush/synchronize outstanding buffers, it looks like
GPU can just have a NOP there.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Fixes: 8bd2fa0 ("virtio: break and reset virtio devices on device_shutdown()")
Cc: Eric Auger <eauger@redhat.com>
Cc: Jocelyn Falempe <jfalempe@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <8490dbeb6f79ed039e6c11d121002618972538a3.1744293540.git.mst@redhat.com>
boryas pushed a commit that referenced this pull request May 21, 2025
Dave Hansen reports the following crash on a 32-bit system with
CONFIG_HIGHMEM=y and CONFIG_X86_PAE=y:

  > 0xf75fe000 is the mem_map[] entry for the first page >4GB. It
  > obviously wasn't allocated, thus the oops.

  BUG: unable to handle page fault for address: f75fe000
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  *pdpt = 0000000002da2001 *pde = 000000000300c067 *pte = 0000000000000000
  Oops: Oops: 0002 [#1] SMP NOPTI
  CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.15.0-rc1-00288-ge618ee89561b-dirty torvalds#311 PREEMPT(undef)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
  EIP: __free_pages_core+0x3c/0x74
  ...
  Call Trace:
   memblock_free_pages+0x11/0x2c
   memblock_free_all+0x2ce/0x3a0
   mm_core_init+0xf5/0x320
   start_kernel+0x296/0x79c
   i386_start_kernel+0xad/0xb0
   startup_32_smp+0x151/0x154

The mem_map[] is allocated up to the end of ZONE_HIGHMEM which is defined
by max_pfn.

The bug was introduced by this recent commit:

  6faea34 ("arch, mm: streamline HIGHMEM freeing")

Previously, freeing of high memory was also clamped to the end of
ZONE_HIGHMEM but after this change, memblock_free_all() tries to
free memory above the of ZONE_HIGHMEM as well and that causes
access to mem_map[] entries beyond the end of the memory map.

To fix this, discard the memory after max_pfn from memblock on
32-bit systems so that core MM would be aware only of actually
usable memory.

Fixes: 6faea34 ("arch, mm: streamline HIGHMEM freeing")
Reported-by: Dave Hansen <dave.hansen@intel.com>
Tested-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Shevchenko <andy@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davide Ciminaghi <ciminaghi@gnudd.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20250413080858.743221-1-rppt@kernel.org # discussion and submission
boryas pushed a commit that referenced this pull request May 21, 2025
syzbot reported:

tipc: Node number set to 1055423674
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events tipc_net_finalize_work
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
...
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

There is a racing condition between workqueue created when enabling
bearer and another thread created when disabling bearer right after
that as follow:

enabling_bearer                          | disabling_bearer
---------------                          | ----------------
tipc_disc_timeout()                      |
{                                        | bearer_disable()
 ...                                     | {
 schedule_work(&tn->work);               |  tipc_mon_delete()
 ...                                     |  {
}                                        |   ...
                                         |   write_lock_bh(&mon->lock);
                                         |   mon->self = NULL;
                                         |   write_unlock_bh(&mon->lock);
                                         |   ...
                                         |  }
tipc_net_finalize_work()                 | }
{                                        |
 ...                                     |
 tipc_net_finalize()                     |
 {                                       |
  ...                                    |
  tipc_mon_reinit_self()                 |
  {                                      |
   ...                                   |
   write_lock_bh(&mon->lock);            |
   mon->self->addr = tipc_own_addr(net); |
   write_unlock_bh(&mon->lock);          |
   ...                                   |
  }                                      |
  ...                                    |
 }                                       |
 ...                                     |
}                                        |

'mon->self' is set to NULL in disabling_bearer thread and dereferenced
later in enabling_bearer thread.

This commit fixes this issue by validating 'mon->self' before assigning
node address to it.

Reported-by: syzbot+ed60da8d686dc709164c@syzkaller.appspotmail.com
Fixes: 46cb01e ("tipc: update mon's self addr when node addr generated")
Signed-off-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250417074826.578115-1-tung.quang.nguyen@est.tech
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
We encountered following crash when testing a XDP_REDIRECT feature
in production:

[56251.579676] list_add corruption. next->prev should be prev (ffff93120dd40f30), but was ffffb301ef3a6740. (next=ffff93120dd
40f30).
[56251.601413] ------------[ cut here ]------------
[56251.611357] kernel BUG at lib/list_debug.c:29!
[56251.621082] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[56251.632073] CPU: 111 UID: 0 PID: 0 Comm: swapper/111 Kdump: loaded Tainted: P           O       6.12.33-cloudflare-2025.6.
3 #1
[56251.653155] Tainted: [P]=PROPRIETARY_MODULE, [O]=OOT_MODULE
[56251.663877] Hardware name: MiTAC GC68B-B8032-G11P6-GPU/S8032GM-HE-CFR, BIOS V7.020.B10-sig 01/22/2025
[56251.682626] RIP: 0010:__list_add_valid_or_report+0x4b/0xa0
[56251.693203] Code: 0e 48 c7 c7 68 e7 d9 97 e8 42 16 fe ff 0f 0b 48 8b 52 08 48 39 c2 74 14 48 89 f1 48 c7 c7 90 e7 d9 97 48
 89 c6 e8 25 16 fe ff <0f> 0b 4c 8b 02 49 39 f0 74 14 48 89 d1 48 c7 c7 e8 e7 d9 97 4c 89
[56251.725811] RSP: 0018:ffff93120dd40b80 EFLAGS: 00010246
[56251.736094] RAX: 0000000000000075 RBX: ffffb301e6bba9d8 RCX: 0000000000000000
[56251.748260] RDX: 0000000000000000 RSI: ffff9149afda0b80 RDI: ffff9149afda0b80
[56251.760349] RBP: ffff9131e49c8000 R08: 0000000000000000 R09: ffff93120dd40a18
[56251.772382] R10: ffff9159cf2ce1a8 R11: 0000000000000003 R12: ffff911a80850000
[56251.784364] R13: ffff93120fbc7000 R14: 0000000000000010 R15: ffff9139e7510e40
[56251.796278] FS:  0000000000000000(0000) GS:ffff9149afd80000(0000) knlGS:0000000000000000
[56251.809133] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[56251.819561] CR2: 00007f5e85e6f300 CR3: 00000038b85e2006 CR4: 0000000000770ef0
[56251.831365] PKRU: 55555554
[56251.838653] Call Trace:
[56251.845560]  <IRQ>
[56251.851943]  cpu_map_enqueue.cold+0x5/0xa
[56251.860243]  xdp_do_redirect+0x2d9/0x480
[56251.868388]  bnxt_rx_xdp+0x1d8/0x4c0 [bnxt_en]
[56251.877028]  bnxt_rx_pkt+0x5f7/0x19b0 [bnxt_en]
[56251.885665]  ? cpu_max_write+0x1e/0x100
[56251.893510]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.902276]  __bnxt_poll_work+0x190/0x340 [bnxt_en]
[56251.911058]  bnxt_poll+0xab/0x1b0 [bnxt_en]
[56251.919041]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.927568]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.935958]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.944250]  __napi_poll+0x2b/0x160
[56251.951155]  bpf_trampoline_6442548651+0x79/0x123
[56251.959262]  __napi_poll+0x5/0x160
[56251.966037]  net_rx_action+0x3d2/0x880
[56251.973133]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.981265]  ? srso_alias_return_thunk+0x5/0xfbef5
[56251.989262]  ? __hrtimer_run_queues+0x162/0x2a0
[56251.996967]  ? srso_alias_return_thunk+0x5/0xfbef5
[56252.004875]  ? srso_alias_return_thunk+0x5/0xfbef5
[56252.012673]  ? bnxt_msix+0x62/0x70 [bnxt_en]
[56252.019903]  handle_softirqs+0xcf/0x270
[56252.026650]  irq_exit_rcu+0x67/0x90
[56252.032933]  common_interrupt+0x85/0xa0
[56252.039498]  </IRQ>
[56252.044246]  <TASK>
[56252.048935]  asm_common_interrupt+0x26/0x40
[56252.055727] RIP: 0010:cpuidle_enter_state+0xb8/0x420
[56252.063305] Code: dc 01 00 00 e8 f9 79 3b ff e8 64 f7 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 a5 32 3a ff 45 84 ff 0f 85 ae
 01 00 00 fb 45 85 f6 <0f> 88 88 01 00 00 48 8b 04 24 49 63 ce 4c 89 ea 48 6b f1 68 48 29
[56252.088911] RSP: 0018:ffff93120c97fe98 EFLAGS: 00000202
[56252.096912] RAX: ffff9149afd80000 RBX: ffff9141d3a72800 RCX: 0000000000000000
[56252.106844] RDX: 00003329176c6b98 RSI: ffffffe36db3fdc7 RDI: 0000000000000000
[56252.116733] RBP: 0000000000000002 R08: 0000000000000002 R09: 000000000000004e
[56252.126652] R10: ffff9149afdb30c4 R11: 071c71c71c71c71c R12: ffffffff985ff860
[56252.136637] R13: 00003329176c6b98 R14: 0000000000000002 R15: 0000000000000000
[56252.146667]  ? cpuidle_enter_state+0xab/0x420
[56252.153909]  cpuidle_enter+0x2d/0x40
[56252.160360]  do_idle+0x176/0x1c0
[56252.166456]  cpu_startup_entry+0x29/0x30
[56252.173248]  start_secondary+0xf7/0x100
[56252.179941]  common_startup_64+0x13e/0x141
[56252.186886]  </TASK>

From the crash dump, we found that the cpu_map_flush_list inside
redirect info is partially corrupted: its list_head->next points to
itself, but list_head->prev points to a valid list of unflushed bq
entries.

This turned out to be a result of missed XDP flush on redirect lists. By
digging in the actual source code, we found that
commit 7f0a168 ("bnxt_en: Add completion ring pointer in TX and RX
ring structures") incorrectly overwrites the event mask for XDP_REDIRECT
in bnxt_rx_xdp. We can stably reproduce this crash by returning XDP_TX
and XDP_REDIRECT randomly for incoming packets in a naive XDP program.
Properly propagate the XDP_REDIRECT events back fixes the crash.

Fixes: a7559bc ("bnxt: support transmit and free of aggregation buffers")
Tested-by: Andrew Rzeznik <arzeznik@cloudflare.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Link: https://patch.msgid.link/aFl7jpCNzscumuN2@debian.debian
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
syzbot complains about an unmapping failure:

[  108.070381][   T14] kernel BUG at mm/gup.c:71!
[  108.070502][   T14] Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
[  108.123672][   T14] Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20250221-8.fc42 02/21/2025
[  108.127458][   T14] Workqueue: iou_exit io_ring_exit_work
[  108.174205][   T14] Call trace:
[  108.175649][   T14]  sanity_check_pinned_pages+0x7cc/0x7d0 (P)
[  108.178138][   T14]  unpin_user_page+0x80/0x10c
[  108.180189][   T14]  io_release_ubuf+0x84/0xf8
[  108.182196][   T14]  io_free_rsrc_node+0x250/0x57c
[  108.184345][   T14]  io_rsrc_data_free+0x148/0x298
[  108.186493][   T14]  io_sqe_buffers_unregister+0x84/0xa0
[  108.188991][   T14]  io_ring_ctx_free+0x48/0x480
[  108.191057][   T14]  io_ring_exit_work+0x764/0x7d8
[  108.193207][   T14]  process_one_work+0x7e8/0x155c
[  108.195431][   T14]  worker_thread+0x958/0xed8
[  108.197561][   T14]  kthread+0x5fc/0x75c
[  108.199362][   T14]  ret_from_fork+0x10/0x20

We can pin a tail page of a folio, but then io_uring will try to unpin
the head page of the folio. While it should be fine in terms of keeping
the page actually alive, mm folks say it's wrong and triggers a debug
warning. Use unpin_user_folio() instead of unpin_user_page*.

Cc: stable@vger.kernel.org
Debugged-by: David Hildenbrand <david@redhat.com>
Reported-by: syzbot+1d335893772467199ab6@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/683f1551.050a0220.55ceb.0017.GAE@google.com
Fixes: a8edbb4 ("io_uring/rsrc: enable multi-hugepage buffer coalescing")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/io-uring/a28b0f87339ac2acf14a645dad1e95bbcbf18acd.1750771718.git.asml.silence@gmail.com/
[axboe: adapt to current tree, massage commit message]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
boryas pushed a commit that referenced this pull request Jul 23, 2025
The issue arises when kzalloc() is invoked while holding umem_mutex or
any other lock acquired under umem_mutex. This is problematic because
kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke
mmu_notifier_invalidate_range_start(). This function can lead to
mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again,
resulting in a deadlock.

The problematic flow:
             CPU0                      |              CPU1
---------------------------------------|------------------------------------------------
mlx5_ib_dereg_mr()                     |
 → revoke_mr()                         |
   → mutex_lock(&umem_odp->umem_mutex) |
                                       | mlx5_mkey_cache_init()
                                       |  → mutex_lock(&dev->cache.rb_lock)
                                       |  → mlx5r_cache_create_ent_locked()
                                       |    → kzalloc(GFP_KERNEL)
                                       |      → fs_reclaim()
                                       |        → mmu_notifier_invalidate_range_start()
                                       |          → mlx5_ib_invalidate_range()
                                       |            → mutex_lock(&umem_odp->umem_mutex)
   → cache_ent_find_and_store()        |
     → mutex_lock(&dev->cache.rb_lock) |

Additionally, when kzalloc() is called from within
cache_ent_find_and_store(), we encounter the same deadlock due to
re-acquisition of umem_mutex.

Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr()
and before acquiring rb_lock. This ensures that we don't hold
umem_mutex while performing memory allocations that could trigger
the reclaim path.

This change prevents the deadlock by ensuring proper lock ordering and
avoiding holding locks during memory allocation operations that could
trigger the reclaim path.

The following lockdep warning demonstrates the deadlock:

 python3/20557 is trying to acquire lock:
 ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at:
 mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]

 but task is already holding lock:
 ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at:
 unmap_vmas+0x7b/0x1a0

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
       fs_reclaim_acquire+0x60/0xd0
       mem_cgroup_css_alloc+0x6f/0x9b0
       cgroup_init_subsys+0xa4/0x240
       cgroup_init+0x1c8/0x510
       start_kernel+0x747/0x760
       x86_64_start_reservations+0x25/0x30
       x86_64_start_kernel+0x73/0x80
       common_startup_64+0x129/0x138

 -> #2 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire+0x91/0xd0
       __kmalloc_cache_noprof+0x4d/0x4c0
       mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib]
       mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib]
       mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib]
       __mlx5_ib_add+0x4b/0x190 [mlx5_ib]
       mlx5r_probe+0xd9/0x320 [mlx5_ib]
       auxiliary_bus_probe+0x42/0x70
       really_probe+0xdb/0x360
       __driver_probe_device+0x8f/0x130
       driver_probe_device+0x1f/0xb0
       __driver_attach+0xd4/0x1f0
       bus_for_each_dev+0x79/0xd0
       bus_add_driver+0xf0/0x200
       driver_register+0x6e/0xc0
       __auxiliary_driver_register+0x6a/0xc0
       do_one_initcall+0x5e/0x390
       do_init_module+0x88/0x240
       init_module_from_file+0x85/0xc0
       idempotent_init_module+0x104/0x300
       __x64_sys_finit_module+0x68/0xc0
       do_syscall_64+0x6d/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 -> #1 (&dev->cache.rb_lock){+.+.}-{4:4}:
       __mutex_lock+0x98/0xf10
       __mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib]
       mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib]
       ib_dereg_mr_user+0x85/0x1f0 [ib_core]
       uverbs_free_mr+0x19/0x30 [ib_uverbs]
       destroy_hw_idr_uobject+0x21/0x80 [ib_uverbs]
       uverbs_destroy_uobject+0x60/0x3d0 [ib_uverbs]
       uobj_destroy+0x57/0xa0 [ib_uverbs]
       ib_uverbs_cmd_verbs+0x4d5/0x1210 [ib_uverbs]
       ib_uverbs_ioctl+0x129/0x230 [ib_uverbs]
       __x64_sys_ioctl+0x596/0xaa0
       do_syscall_64+0x6d/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 -> #0 (&umem_odp->umem_mutex){+.+.}-{4:4}:
       __lock_acquire+0x1826/0x2f00
       lock_acquire+0xd3/0x2e0
       __mutex_lock+0x98/0xf10
       mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]
       __mmu_notifier_invalidate_range_start+0x18e/0x1f0
       unmap_vmas+0x182/0x1a0
       exit_mmap+0xf3/0x4a0
       mmput+0x3a/0x100
       do_exit+0x2b9/0xa90
       do_group_exit+0x32/0xa0
       get_signal+0xc32/0xcb0
       arch_do_signal_or_restart+0x29/0x1d0
       syscall_exit_to_user_mode+0x105/0x1d0
       do_syscall_64+0x79/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 Chain exists of:
 &dev->cache.rb_lock --> mmu_notifier_invalidate_range_start -->
 &umem_odp->umem_mutex

 Possible unsafe locking scenario:

       CPU0                        CPU1
       ----                        ----
   lock(&umem_odp->umem_mutex);
                                lock(mmu_notifier_invalidate_range_start);
                                lock(&umem_odp->umem_mutex);
   lock(&dev->cache.rb_lock);

 *** DEADLOCK ***

Fixes: abb604a ("RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error")
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/3c8f225a8a9fade647d19b014df1172544643e4a.1750061612.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Add 0x29 as the accelerometer address for the Dell Latitude 5500 to
lis3lv02d_devices[].

The address was verified as below:

    $ cd /sys/bus/pci/drivers/i801_smbus/0000:00:1f.4
    $ ls -d i2c-?
    i2c-2
    $ sudo modprobe i2c-dev
    $ sudo i2cdetect 2
    WARNING! This program can confuse your I2C bus, cause data loss and worse!
    I will probe file /dev/i2c-2.
    I will probe address range 0x08-0x77.
    Continue? [Y/n] Y
         0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
    00:                         08 -- -- -- -- -- -- --
    10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    20: -- -- -- -- -- -- -- -- -- 29 -- -- -- -- -- --
    30: 30 -- -- -- -- 35 UU UU -- -- -- -- -- -- -- --
    40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- --
    50: UU -- 52 -- -- -- -- -- -- -- -- -- -- -- -- --
    60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
    70: -- -- -- -- -- -- -- --
    $ echo lis3lv02d 0x29 | sudo tee /sys/bus/i2c/devices/i2c-2/new_device
    lis3lv02d 0x29
    $ sudo dmesg
    [    0.000000] Linux version 6.12.32-amd64 (debian-kernel@lists.debian.org) (x86_64-linux-gnu-gcc-14 (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44) #1 SMP PREEMPT_DYNAMIC Debian 6.12.32-1 (2025-06-07)
    […]
    [    0.000000] DMI: Dell Inc. Latitude 5500/0M14W7, BIOS 1.38.0 03/06/2025
    […]
    [  609.063488] i2c_dev: i2c /dev entries driver
    [  639.135020] i2c i2c-2: new_device: Instantiated device lis3lv02d at 0x29

Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Hans de Goede <hansg@kernel.org>
Link: https://lore.kernel.org/r/20250622080721.4661-1-pmenzel@molgen.mpg.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
While testing null_blk with configfs, echo 0 > poll_queues will trigger
following panic:

BUG: kernel NULL pointer dereference, address: 0000000000000010
Oops: Oops: 0000 [#1] SMP NOPTI
CPU: 27 UID: 0 PID: 920 Comm: bash Not tainted 6.15.0-02023-gadbdb95c8696-dirty torvalds#1238 PREEMPT(undef)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014
RIP: 0010:__bitmap_or+0x48/0x70
Call Trace:
 <TASK>
 __group_cpus_evenly+0x822/0x8c0
 group_cpus_evenly+0x2d9/0x490
 blk_mq_map_queues+0x1e/0x110
 null_map_queues+0xc9/0x170 [null_blk]
 blk_mq_update_queue_map+0xdb/0x160
 blk_mq_update_nr_hw_queues+0x22b/0x560
 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk]
 nullb_device_poll_queues_store+0xa4/0x130 [null_blk]
 configfs_write_iter+0x109/0x1d0
 vfs_write+0x26e/0x6f0
 ksys_write+0x79/0x180
 __x64_sys_write+0x1d/0x30
 x64_sys_call+0x45c4/0x45f0
 do_syscall_64+0xa5/0x240
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Root cause is that numgrps is set to 0, and ZERO_SIZE_PTR is returned from
kcalloc(), and later ZERO_SIZE_PTR will be deferenced.

Fix the problem by checking numgrps first in group_cpus_evenly(), and
return NULL directly if numgrps is zero.

[yukuai3@huawei.com: also fix the non-SMP version]
  Link: https://lkml.kernel.org/r/20250620010958.1265984-1-yukuai1@huaweicloud.com
Link: https://lkml.kernel.org/r/20250619132655.3318883-1-yukuai1@huaweicloud.com
Fixes: 6a6dcae ("blk-mq: Build default queue map via group_cpus_evenly()")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: ErKun Yang <yangerkun@huawei.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: "zhangyi (F)" <yi.zhang@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
While we are indirectly draining our dedicated workqueue ggtt->wq
that we use to complete asynchronous removal of some GGTT nodes,
this happends as part of the managed-drm unwinding (ggtt_fini_early),
which could be later then manage-device unwinding, where we could
already unmap our MMIO/GMS mapping (mmio_fini).

This was recently observed during unsuccessful VF initialization:

 [ ] xe 0000:00:02.1: probe with driver xe failed with error -62
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747340 __xe_bo_unpin_map_no_vm (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747540 __xe_bo_unpin_map_no_vm (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747240 __xe_bo_unpin_map_no_vm (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747040 tiles_fini (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e746840 mmio_fini (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e747f40 xe_bo_pinned_fini (16 bytes)
 [ ] xe 0000:00:02.1: DEVRES REL ffff88811e746b40 devm_drm_dev_init_release (16 bytes)
 [ ] xe 0000:00:02.1: [drm:drm_managed_release] drmres release begin
 [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef81640 __fini_relay (8 bytes)
 [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80d40 guc_ct_fini (8 bytes)
 [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80040 __drmm_mutex_release (8 bytes)
 [ ] xe 0000:00:02.1: [drm:drm_managed_release] REL ffff88810ef80140 ggtt_fini_early (8 bytes)

and this was leading to:

 [ ] BUG: unable to handle page fault for address: ffffc900058162a0
 [ ] #PF: supervisor write access in kernel mode
 [ ] #PF: error_code(0x0002) - not-present page
 [ ] Oops: Oops: 0002 [#1] SMP NOPTI
 [ ] Tainted: [W]=WARN
 [ ] Workqueue: xe-ggtt-wq ggtt_node_remove_work_func [xe]
 [ ] RIP: 0010:xe_ggtt_set_pte+0x6d/0x350 [xe]
 [ ] Call Trace:
 [ ]  <TASK>
 [ ]  xe_ggtt_clear+0xb0/0x270 [xe]
 [ ]  ggtt_node_remove+0xbb/0x120 [xe]
 [ ]  ggtt_node_remove_work_func+0x30/0x50 [xe]
 [ ]  process_one_work+0x22b/0x6f0
 [ ]  worker_thread+0x1e8/0x3d

Add managed-device action that will explicitly drain the workqueue
with all pending node removals prior to releasing MMIO/GSM mapping.

Fixes: 919bb54 ("drm/xe: Fix missing runtime outer protection for ggtt_remove_node")
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://lore.kernel.org/r/20250612220937.857-2-michal.wajdeczko@intel.com
(cherry picked from commit 89d2835)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order
and prevent the following deadlock from happening

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-build2+ torvalds#1301 Tainted: G S      W
------------------------------------------------------
cifsd/6055 is trying to acquire lock:
ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200

but task is already holding lock:
ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_setup_session+0x81/0x4b0
       cifs_get_smb_ses+0x771/0x900
       cifs_mount_get_session+0x7e/0x170
       cifs_mount+0x92/0x2d0
       cifs_smb3_do_mount+0x161/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #1 (&ret_buf->ses_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_match_super+0x101/0x320
       sget+0xab/0x270
       cifs_smb3_do_mount+0x1e0/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}:
       check_noncircular+0x95/0xc0
       check_prev_add+0x115/0x2f0
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_signal_cifsd_for_reconnect+0x134/0x200
       __cifs_reconnect+0x8f/0x500
       cifs_handle_standard+0x112/0x280
       cifs_demultiplex_thread+0x64d/0xbc0
       kthread+0x2f7/0x310
       ret_from_fork+0x2a/0x230
       ret_from_fork_asm+0x1a/0x30

other info that might help us debug this:

Chain exists of:
  &tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ret_buf->chan_lock);
                               lock(&ret_buf->ses_lock);
                               lock(&ret_buf->chan_lock);
  lock(&tcp_ses->srv_lock);

 *** DEADLOCK ***

3 locks held by cifsd/6055:
 #0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200
 #1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200
 #2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

Cc: linux-cifs@vger.kernel.org
Reported-by: David Howells <dhowells@redhat.com>
Fixes: d7d7a66 ("cifs: avoid use of global locks for high contention data")
Reviewed-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
The 'icc_bw_lock' mutex is introduced in commit af42269
("interconnect: Fix locking for runpm vs reclaim") in order to decouple
serialization of bw aggregation from codepaths that require memory
allocation.

However commit d30f83d ("interconnect: core: Add dynamic id
allocation support") added a devm_kasprintf() call into a path protected
by the 'icc_bw_lock' which causes the following lockdep warning on
machines like the Lenovo ThinkPad X13s:

    ======================================================
    WARNING: possible circular locking dependency detected
    6.16.0-rc3 torvalds#15 Not tainted
    ------------------------------------------------------
    (udev-worker)/342 is trying to acquire lock:
    ffffb973f7ec4638 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_node_track_caller_noprof+0xa0/0x3e0

    but task is already holding lock:
    ffffb973f7f7f0e8 (icc_bw_lock){+.+.}-{4:4}, at: icc_node_add+0x44/0x154

    which lock already depends on the new lock.

    the existing dependency chain (in reverse order) is:

    -> #1 (icc_bw_lock){+.+.}-{4:4}:
           icc_init+0x48/0x108
           do_one_initcall+0x64/0x30c
           kernel_init_freeable+0x27c/0x500
           kernel_init+0x20/0x1d8
           ret_from_fork+0x10/0x20

    -> #0 (fs_reclaim){+.+.}-{0:0}:
           __lock_acquire+0x136c/0x2114
           lock_acquire+0x1c8/0x354
           fs_reclaim_acquire+0x74/0xa8
           __kmalloc_node_track_caller_noprof+0xa0/0x3e0
           devm_kmalloc+0x54/0x124
           devm_kvasprintf+0x74/0xd4
           devm_kasprintf+0x58/0x80
           icc_node_add+0xb4/0x154
           qcom_osm_l3_probe+0x20c/0x314 [icc_osm_l3]
           platform_probe+0x68/0xd8
           really_probe+0xc0/0x38c
           __driver_probe_device+0x7c/0x160
           driver_probe_device+0x40/0x110
           __driver_attach+0xfc/0x208
           bus_for_each_dev+0x74/0xd0
           driver_attach+0x24/0x30
           bus_add_driver+0x110/0x234
           driver_register+0x60/0x128
           __platform_driver_register+0x24/0x30
           osm_l3_driver_init+0x20/0x1000 [icc_osm_l3]
           do_one_initcall+0x64/0x30c
           do_init_module+0x58/0x23c
           load_module+0x1df8/0x1f70
           init_module_from_file+0x88/0xc4
           idempotent_init_module+0x188/0x280
           __arm64_sys_finit_module+0x6c/0xd8
           invoke_syscall+0x48/0x110
           el0_svc_common.constprop.0+0xc0/0xe0
           do_el0_svc+0x1c/0x28
           el0_svc+0x4c/0x158
           el0t_64_sync_handler+0xc8/0xcc
           el0t_64_sync+0x198/0x19c

    other info that might help us debug this:

     Possible unsafe locking scenario:

           CPU0                    CPU1
           ----                    ----
      lock(icc_bw_lock);
                                   lock(fs_reclaim);
                                   lock(icc_bw_lock);
      lock(fs_reclaim);

     *** DEADLOCK ***

The icc_node_add() functions is not designed to fail, and as such it
should not do any memory allocation. In order to avoid this, add a new
helper function for the name generation to be called by drivers which
are using the new dynamic id feature.

Fixes: d30f83d ("interconnect: core: Add dynamic id allocation support")
Signed-off-by: Gabor Juhos <j4g8y7@gmail.com>
Link: https://lore.kernel.org/r/20250625-icc-bw-lockdep-v3-1-2b8f8b8987c4@gmail.com
Co-developed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20250627075854.26943-1-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
On MicroChip MPFS Icicle:

  microchip-pcie 2000000000.pcie: host bridge /soc/pcie@2000000000 ranges:
  microchip-pcie 2000000000.pcie: Parsing ranges property...
  microchip-pcie 2000000000.pcie:      MEM 0x2008000000..0x2087ffffff -> 0x0008000000
  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000368
  Current swapper/0 pgtable: 4K pagesize, 39-bit VAs, pgdp=0x00000000814f1000
  [0000000000000368] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
  Oops [#1]
  Modules linked in:
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.15.0-rc1-icicle-00003-gafc0a570bb61 torvalds#232 NONE
  Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
  [...]
  [<ffffffff803fb8a4>] plda_pcie_setup_iomems+0xe/0x78
  [<ffffffff803fc246>] mc_platform_init+0x80/0x1d2
  [<ffffffff803f9c88>] pci_ecam_create+0x104/0x1e2
  [<ffffffff8000adbe>] pci_host_common_init+0x120/0x228
  [<ffffffff8000af42>] pci_host_common_probe+0x7c/0x8a

The initialization of driver_data was moved after the call to
gen_pci_init(), while the pci_ecam_ops.init() callback
mc_platform_init() expects it has already been initialized.

Fix this by moving the initialization of driver_data up.

Fixes: afc0a57 ("PCI: host-generic: Extract an ECAM bridge creation helper from pci_host_common_probe()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/774290708a6f0f683711914fda110742c18a7fb2.1750787223.git.geert+renesas@glider.be
Link: https://patch.msgid.link/20250625111806.4153773-2-maz@kernel.org
boryas pushed a commit that referenced this pull request Jul 23, 2025
When I run the NVME over TCP test in virtme-ng, I get the following
"suspicious RCU usage" warning in nvme_mpath_add_sysfs_link():

'''
[    5.024557][   T44] nvmet: Created nvm controller 1 for subsystem nqn.2025-06.org.nvmexpress.mptcp for NQN nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77.
[    5.027401][  T183] nvme nvme0: creating 2 I/O queues.
[    5.029017][  T183] nvme nvme0: mapped 2/0/0 default/read/poll queues.
[    5.032587][  T183] nvme nvme0: new ctrl: NQN "nqn.2025-06.org.nvmexpress.mptcp", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77
[    5.042214][   T25]
[    5.042440][   T25] =============================
[    5.042579][   T25] WARNING: suspicious RCU usage
[    5.042705][   T25] 6.16.0-rc3+ torvalds#23 Not tainted
[    5.042812][   T25] -----------------------------
[    5.042934][   T25] drivers/nvme/host/multipath.c:1203 RCU-list traversed in non-reader section!!
[    5.043111][   T25]
[    5.043111][   T25] other info that might help us debug this:
[    5.043111][   T25]
[    5.043341][   T25]
[    5.043341][   T25] rcu_scheduler_active = 2, debug_locks = 1
[    5.043502][   T25] 3 locks held by kworker/u9:0/25:
[    5.043615][   T25]  #0: ffff888008730948 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x7ed/0x1350
[    5.043830][   T25]  #1: ffffc900001afd40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0xcf3/0x1350
[    5.044084][   T25]  #2: ffff888013ee0020 (&head->srcu){.+.+}-{0:0}, at: nvme_mpath_add_sysfs_link.part.0+0xb4/0x3a0
[    5.044300][   T25]
[    5.044300][   T25] stack backtrace:
[    5.044439][   T25] CPU: 0 UID: 0 PID: 25 Comm: kworker/u9:0 Not tainted 6.16.0-rc3+ torvalds#23 PREEMPT(full)
[    5.044441][   T25] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    5.044442][   T25] Workqueue: async async_run_entry_fn
[    5.044445][   T25] Call Trace:
[    5.044446][   T25]  <TASK>
[    5.044449][   T25]  dump_stack_lvl+0x6f/0xb0
[    5.044453][   T25]  lockdep_rcu_suspicious.cold+0x4f/0xb1
[    5.044457][   T25]  nvme_mpath_add_sysfs_link.part.0+0x2fb/0x3a0
[    5.044459][   T25]  ? queue_work_on+0x90/0xf0
[    5.044461][   T25]  ? lockdep_hardirqs_on+0x78/0x110
[    5.044466][   T25]  nvme_mpath_set_live+0x1e9/0x4f0
[    5.044470][   T25]  nvme_mpath_add_disk+0x240/0x2f0
[    5.044472][   T25]  ? __pfx_nvme_mpath_add_disk+0x10/0x10
[    5.044475][   T25]  ? add_disk_fwnode+0x361/0x580
[    5.044480][   T25]  nvme_alloc_ns+0x81c/0x17c0
[    5.044483][   T25]  ? kasan_quarantine_put+0x104/0x240
[    5.044487][   T25]  ? __pfx_nvme_alloc_ns+0x10/0x10
[    5.044495][   T25]  ? __pfx_nvme_find_get_ns+0x10/0x10
[    5.044496][   T25]  ? rcu_read_lock_any_held+0x45/0xa0
[    5.044498][   T25]  ? validate_chain+0x232/0x4f0
[    5.044503][   T25]  nvme_scan_ns+0x4c8/0x810
[    5.044506][   T25]  ? __pfx_nvme_scan_ns+0x10/0x10
[    5.044508][   T25]  ? find_held_lock+0x2b/0x80
[    5.044512][   T25]  ? ktime_get+0x16d/0x220
[    5.044517][   T25]  ? kvm_clock_get_cycles+0x18/0x30
[    5.044520][   T25]  ? __pfx_nvme_scan_ns_async+0x10/0x10
[    5.044522][   T25]  async_run_entry_fn+0x97/0x560
[    5.044523][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044526][   T25]  process_one_work+0xd3c/0x1350
[    5.044532][   T25]  ? __pfx_process_one_work+0x10/0x10
[    5.044536][   T25]  ? assign_work+0x16c/0x240
[    5.044539][   T25]  worker_thread+0x4da/0xd50
[    5.044545][   T25]  ? __pfx_worker_thread+0x10/0x10
[    5.044546][   T25]  kthread+0x356/0x5c0
[    5.044548][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044549][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044552][   T25]  ? __lock_release.isra.0+0x5d/0x180
[    5.044553][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044555][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044557][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044559][   T25]  ret_from_fork+0x218/0x2e0
[    5.044561][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044562][   T25]  ret_from_fork_asm+0x1a/0x30
[    5.044570][   T25]  </TASK>
'''

This patch uses sleepable RCU version of helper list_for_each_entry_srcu()
instead of list_for_each_entry_rcu() to fix it.

Fixes: 4dbd2b2 ("nvme-multipath: Add visibility for round-robin io-policy")
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
boryas pushed a commit that referenced this pull request Jul 23, 2025
With VIRTCHNL2_CAP_MACFILTER enabled, the following warning is generated
on module load:

[  324.701677] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:578
[  324.701684] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1582, name: NetworkManager
[  324.701689] preempt_count: 201, expected: 0
[  324.701693] RCU nest depth: 0, expected: 0
[  324.701697] 2 locks held by NetworkManager/1582:
[  324.701702]  #0: ffffffff9f7be770 (rtnl_mutex){....}-{3:3}, at: rtnl_newlink+0x791/0x21e0
[  324.701730]  #1: ff1100216c380368 (_xmit_ETHER){....}-{2:2}, at: __dev_open+0x3f0/0x870
[  324.701749] Preemption disabled at:
[  324.701752] [<ffffffff9cd23b9d>] __dev_open+0x3dd/0x870
[  324.701765] CPU: 30 UID: 0 PID: 1582 Comm: NetworkManager Not tainted 6.15.0-rc5+ #2 PREEMPT(voluntary)
[  324.701771] Hardware name: Intel Corporation M50FCP2SBSTD/M50FCP2SBSTD, BIOS SE5C741.86B.01.01.0001.2211140926 11/14/2022
[  324.701774] Call Trace:
[  324.701777]  <TASK>
[  324.701779]  dump_stack_lvl+0x5d/0x80
[  324.701788]  ? __dev_open+0x3dd/0x870
[  324.701793]  __might_resched.cold+0x1ef/0x23d
<..>
[  324.701818]  __mutex_lock+0x113/0x1b80
<..>
[  324.701917]  idpf_ctlq_clean_sq+0xad/0x4b0 [idpf]
[  324.701935]  ? kasan_save_track+0x14/0x30
[  324.701941]  idpf_mb_clean+0x143/0x380 [idpf]
<..>
[  324.701991]  idpf_send_mb_msg+0x111/0x720 [idpf]
[  324.702009]  idpf_vc_xn_exec+0x4cc/0x990 [idpf]
[  324.702021]  ? rcu_is_watching+0x12/0xc0
[  324.702035]  idpf_add_del_mac_filters+0x3ed/0xb50 [idpf]
<..>
[  324.702122]  __hw_addr_sync_dev+0x1cf/0x300
[  324.702126]  ? find_held_lock+0x32/0x90
[  324.702134]  idpf_set_rx_mode+0x317/0x390 [idpf]
[  324.702152]  __dev_open+0x3f8/0x870
[  324.702159]  ? __pfx___dev_open+0x10/0x10
[  324.702174]  __dev_change_flags+0x443/0x650
<..>
[  324.702208]  netif_change_flags+0x80/0x160
[  324.702218]  do_setlink.isra.0+0x16a0/0x3960
<..>
[  324.702349]  rtnl_newlink+0x12fd/0x21e0

The sequence is as follows:
	rtnl_newlink()->
	__dev_change_flags()->
	__dev_open()->
	dev_set_rx_mode() - >  # disables BH and grabs "dev->addr_list_lock"
	idpf_set_rx_mode() ->  # proceed only if VIRTCHNL2_CAP_MACFILTER is ON
	__dev_uc_sync() ->
	idpf_add_mac_filter ->
	idpf_add_del_mac_filters ->
	idpf_send_mb_msg() ->
	idpf_mb_clean() ->
	idpf_ctlq_clean_sq()   # mutex_lock(cq_lock)

Fix by converting cq_lock to a spinlock. All operations under the new
lock are safe except freeing the DMA memory, which may use vunmap(). Fix
by requesting a contiguous physical memory for the DMA mapping.

Fixes: a251eee ("idpf: add SRIOV support and other ndo_ops")
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Mitigate e.g. the following:

    # echo 1e789080.lpc-snoop > /sys/bus/platform/drivers/aspeed-lpc-snoop/unbind
    ...
    [  120.363594] Unable to handle kernel NULL pointer dereference at virtual address 00000004 when write
    [  120.373866] [00000004] *pgd=00000000
    [  120.377910] Internal error: Oops: 805 [#1] SMP ARM
    [  120.383306] CPU: 1 UID: 0 PID: 315 Comm: sh Not tainted 6.15.0-rc1-00009-g926217bc7d7d-dirty torvalds#20 NONE
    ...
    [  120.679543] Call trace:
    [  120.679559]  misc_deregister from aspeed_lpc_snoop_remove+0x84/0xac
    [  120.692462]  aspeed_lpc_snoop_remove from platform_remove+0x28/0x38
    [  120.700996]  platform_remove from device_release_driver_internal+0x188/0x200
    ...

Fixes: 9f4f9ae ("drivers/misc: add Aspeed LPC snoop driver")
Cc: stable@vger.kernel.org
Cc: Jean Delvare <jdelvare@suse.de>
Acked-by: Jean Delvare <jdelvare@suse.de>
Link: https://patch.msgid.link/20250616-aspeed-lpc-snoop-fixes-v2-2-3cdd59c934d3@codeconstruct.com.au
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Currently, an interrupt can be triggered during a GPU reset, which can
lead to GPU hangs and NULL pointer dereference in an interrupt context
as shown in the following trace:

 [  314.035040] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0
 [  314.043822] Mem abort info:
 [  314.046606]   ESR = 0x0000000096000005
 [  314.050347]   EC = 0x25: DABT (current EL), IL = 32 bits
 [  314.055651]   SET = 0, FnV = 0
 [  314.058695]   EA = 0, S1PTW = 0
 [  314.061826]   FSC = 0x05: level 1 translation fault
 [  314.066694] Data abort info:
 [  314.069564]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
 [  314.075039]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
 [  314.080080]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 [  314.085382] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000102728000
 [  314.091814] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
 [  314.100511] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
 [  314.106770] Modules linked in: v3d i2c_brcmstb vc4 snd_soc_hdmi_codec gpu_sched drm_shmem_helper drm_display_helper cec drm_dma_helper drm_kms_helper drm drm_panel_orientation_quirks snd_soc_core snd_compress snd_pcm_dmaengine snd_pcm snd_timer snd backlight
 [  314.129654] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.25+rpt-rpi-v8 #1  Debian 1:6.12.25-1+rpt1
 [  314.139388] Hardware name: Raspberry Pi 4 Model B Rev 1.4 (DT)
 [  314.145211] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 [  314.152165] pc : v3d_irq+0xec/0x2e0 [v3d]
 [  314.156187] lr : v3d_irq+0xe0/0x2e0 [v3d]
 [  314.160198] sp : ffffffc080003ea0
 [  314.163502] x29: ffffffc080003ea0 x28: ffffffec1f184980 x27: 021202b000000000
 [  314.170633] x26: ffffffec1f17f630 x25: ffffff8101372000 x24: ffffffec1f17d9f0
 [  314.177764] x23: 000000000000002a x22: 000000000000002a x21: ffffff8103252000
 [  314.184895] x20: 0000000000000001 x19: 00000000deadbeef x18: 0000000000000000
 [  314.192026] x17: ffffff94e51d2000 x16: ffffffec1dac3cb0 x15: c306000000000000
 [  314.199156] x14: 0000000000000000 x13: b2fc982e03cc5168 x12: 0000000000000001
 [  314.206286] x11: ffffff8103f8bcc0 x10: ffffffec1f196868 x9 : ffffffec1dac3874
 [  314.213416] x8 : 0000000000000000 x7 : 0000000000042a3a x6 : ffffff810017a180
 [  314.220547] x5 : ffffffec1ebad400 x4 : ffffffec1ebad320 x3 : 00000000000bebeb
 [  314.227677] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
 [  314.234807] Call trace:
 [  314.237243]  v3d_irq+0xec/0x2e0 [v3d]
 [  314.240906]  __handle_irq_event_percpu+0x58/0x218
 [  314.245609]  handle_irq_event+0x54/0xb8
 [  314.249439]  handle_fasteoi_irq+0xac/0x240
 [  314.253527]  handle_irq_desc+0x48/0x68
 [  314.257269]  generic_handle_domain_irq+0x24/0x38
 [  314.261879]  gic_handle_irq+0x48/0xd8
 [  314.265533]  call_on_irq_stack+0x24/0x58
 [  314.269448]  do_interrupt_handler+0x88/0x98
 [  314.273624]  el1_interrupt+0x34/0x68
 [  314.277193]  el1h_64_irq_handler+0x18/0x28
 [  314.281281]  el1h_64_irq+0x64/0x68
 [  314.284673]  default_idle_call+0x3c/0x168
 [  314.288675]  do_idle+0x1fc/0x230
 [  314.291895]  cpu_startup_entry+0x3c/0x50
 [  314.295810]  rest_init+0xe4/0xf0
 [  314.299030]  start_kernel+0x5e8/0x790
 [  314.302684]  __primary_switched+0x80/0x90
 [  314.306691] Code: 940029eb 360ffc13 f9442ea0 52800001 (f9406017)
 [  314.312775] ---[ end trace 0000000000000000 ]---
 [  314.317384] Kernel panic - not syncing: Oops: Fatal exception in interrupt
 [  314.324249] SMP: stopping secondary CPUs
 [  314.328167] Kernel Offset: 0x2b9da00000 from 0xffffffc080000000
 [  314.334076] PHYS_OFFSET: 0x0
 [  314.336946] CPU features: 0x08,00002013,c0200000,0200421b
 [  314.342337] Memory Limit: none
 [  314.345382] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

Before resetting the GPU, it's necessary to disable all interrupts and
deal with any interrupt handler still in-flight. Otherwise, the GPU might
reset with jobs still running, or yet, an interrupt could be handled
during the reset.

Cc: stable@vger.kernel.org
Fixes: 57692c9 ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+")
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Link: https://lore.kernel.org/r/20250628224243.47599-1-mcanal@igalia.com
Signed-off-by: Maíra Canal <mcanal@igalia.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Since we're accessing btree_trans objects owned by another thread, we
need to guard against using pointers to freed key cache entries: we need
our own srcu read lock, and we should skip a btree_trans if it didn't
hold the srcu lock (and thus it might have pointers to freed key cache
entries).

00693 Mem abort info:
00693   ESR = 0x0000000096000005
00693   EC = 0x25: DABT (current EL), IL = 32 bits
00693   SET = 0, FnV = 0
00693   EA = 0, S1PTW = 0
00693   FSC = 0x05: level 1 translation fault
00693 Data abort info:
00693   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
00693   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
00693   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
00693 user pgtable: 4k pages, 39-bit VAs, pgdp=000000012e650000
00693 [000000008fb96218] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
00693 Internal error: Oops: 0000000096000005 [#1]  SMP
00693 Modules linked in:
00693 CPU: 0 UID: 0 PID: 4307 Comm: cat Not tainted 6.16.0-rc2-ktest-g9e15af94fd86 #27578 NONE
00693 Hardware name: linux,dummy-virt (DT)
00693 pstate: 60001005 (nZCv daif -PAN -UAO -TCO -DIT +SSBS BTYPE=--)
00693 pc : six_lock_counts+0x20/0xe8
00693 lr : bch2_btree_bkey_cached_common_to_text+0x38/0x130
00693 sp : ffffff80ca98bb60
00693 x29: ffffff80ca98bb60 x28: 000000008fb96200 x27: 0000000000000007
00693 x26: ffffff80eafd06b8 x25: 0000000000000000 x24: ffffffc080d75a60
00693 x23: ffffff80eafd0000 x22: ffffffc080bdfcc0 x21: ffffff80eafd0210
00693 x20: ffffff80c192ff08 x19: 000000008fb96200 x18: 00000000ffffffff
00693 x17: 0000000000000000 x16: 0000000000000000 x15: 00000000ffffffff
00693 x14: 0000000000000000 x13: ffffff80ceb5a29a x12: 20796220646c6568
00693 x11: 72205d3e303c5b20 x10: 0000000000000020 x9 : ffffffc0805fb6b0
00693 x8 : 0000000000000020 x7 : 0000000000000000 x6 : 0000000000000020
00693 x5 : ffffff80ceb5a29c x4 : 0000000000000001 x3 : 000000000000029c
00693 x2 : 0000000000000000 x1 : ffffff80ef66c000 x0 : 000000008fb96200
00693 Call trace:
00693  six_lock_counts+0x20/0xe8 (P)
00693  bch2_btree_bkey_cached_common_to_text+0x38/0x130
00693  bch2_btree_trans_to_text+0x260/0x2a8
00693  bch2_btree_transactions_read+0xac/0x1e8
00693  full_proxy_read+0x74/0xd8
00693  vfs_read+0x90/0x300
00693  ksys_read+0x6c/0x108
00693  __arm64_sys_read+0x20/0x30
00693  invoke_syscall.constprop.0+0x54/0xe8
00693  do_el0_svc+0x44/0xc8
00693  el0_svc+0x18/0x58
00693  el0t_64_sync_handler+0x104/0x130
00693  el0t_64_sync+0x154/0x158
00693 Code: 910003fd f9423c22 f90017e2 d2800002 (f9400c01)
00693 ---[ end trace 0000000000000000 ]---

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Initialize u64 stats as it uses seq counter on 32bit machines
as suggested by lockdep below.

[    1.830953][    T1] INFO: trying to register non-static key.
[    1.830993][    T1] The code is fine but needs lockdep annotation, or maybe
[    1.831027][    T1] you didn't initialize this object before use?
[    1.831057][    T1] turning off the locking correctness validator.
[    1.831090][    T1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W           6.16.0-rc2-v7l+ #1 PREEMPT
[    1.831097][    T1] Tainted: [W]=WARN
[    1.831099][    T1] Hardware name: BCM2711
[    1.831101][    T1] Call trace:
[    1.831104][    T1]  unwind_backtrace from show_stack+0x18/0x1c
[    1.831120][    T1]  show_stack from dump_stack_lvl+0x8c/0xcc
[    1.831129][    T1]  dump_stack_lvl from register_lock_class+0x9e8/0x9fc
[    1.831141][    T1]  register_lock_class from __lock_acquire+0x420/0x22c0
[    1.831154][    T1]  __lock_acquire from lock_acquire+0x130/0x3f8
[    1.831166][    T1]  lock_acquire from bcmgenet_get_stats64+0x4a4/0x4c8
[    1.831176][    T1]  bcmgenet_get_stats64 from dev_get_stats+0x4c/0x408
[    1.831184][    T1]  dev_get_stats from rtnl_fill_stats+0x38/0x120
[    1.831193][    T1]  rtnl_fill_stats from rtnl_fill_ifinfo+0x7f8/0x1890
[    1.831203][    T1]  rtnl_fill_ifinfo from rtmsg_ifinfo_build_skb+0xd0/0x138
[    1.831214][    T1]  rtmsg_ifinfo_build_skb from rtmsg_ifinfo+0x48/0x8c
[    1.831225][    T1]  rtmsg_ifinfo from register_netdevice+0x8c0/0x95c
[    1.831237][    T1]  register_netdevice from register_netdev+0x28/0x40
[    1.831247][    T1]  register_netdev from bcmgenet_probe+0x690/0x6bc
[    1.831255][    T1]  bcmgenet_probe from platform_probe+0x64/0xbc
[    1.831263][    T1]  platform_probe from really_probe+0xd0/0x2d4
[    1.831269][    T1]  really_probe from __driver_probe_device+0x90/0x1a4
[    1.831273][    T1]  __driver_probe_device from driver_probe_device+0x38/0x11c
[    1.831278][    T1]  driver_probe_device from __driver_attach+0x9c/0x18c
[    1.831282][    T1]  __driver_attach from bus_for_each_dev+0x84/0xd4
[    1.831291][    T1]  bus_for_each_dev from bus_add_driver+0xd4/0x1f4
[    1.831303][    T1]  bus_add_driver from driver_register+0x88/0x120
[    1.831312][    T1]  driver_register from do_one_initcall+0x78/0x360
[    1.831320][    T1]  do_one_initcall from kernel_init_freeable+0x2bc/0x314
[    1.831331][    T1]  kernel_init_freeable from kernel_init+0x1c/0x144
[    1.831339][    T1]  kernel_init from ret_from_fork+0x14/0x20
[    1.831344][    T1] Exception stack(0xf082dfb0 to 0xf082dff8)
[    1.831349][    T1] dfa0:                                     00000000 00000000 00000000 00000000
[    1.831353][    T1] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    1.831356][    T1] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000

Fixes: 59aa6e3 ("net: bcmgenet: switch to use 64bit statistics")
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Ryo Takakura <ryotkkr98@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702092417.46486-1-ryotkkr98@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Transport assignment may race with module unload. Protect new_transport
from becoming a stale pointer.

This also takes care of an insecure call in vsock_use_local_transport();
add a lockdep assert.

BUG: unable to handle page fault for address: fffffbfff8056000
Oops: Oops: 0000 [#1] SMP KASAN
RIP: 0010:vsock_assign_transport+0x366/0x600
Call Trace:
 vsock_connect+0x59c/0xc40
 __sys_connect+0xe8/0x100
 __x64_sys_connect+0x6e/0xc0
 do_syscall_64+0x92/0x1c0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: c0cfa2d ("vsock: add multi-transports support")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250703-vsock-transports-toctou-v4-2-98f0eb530747@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
syzbot reported the splat below. [0]

This happens if we call ioctl(ATMARP_MKIP) more than once.

During the first call, clip_mkip() sets clip_push() to vcc->push(),
and the second call copies it to clip_vcc->old_push().

Later, when the socket is close()d, vcc_destroy_socket() passes
NULL skb to clip_push(), which calls clip_vcc->old_push(),
triggering the infinite recursion.

Let's prevent the second ioctl(ATMARP_MKIP) by checking
vcc->user_back, which is allocated by the first call as clip_vcc.

Note also that we use lock_sock() to prevent racy calls.

[0]:
BUG: TASK stack guard page was hit at ffffc9000d66fff8 (stack is ffffc9000d670000..ffffc9000d678000)
Oops: stack guard page: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:clip_push+0x5/0x720 net/atm/clip.c:191
Code: e0 8f aa 8c e8 1c ad 5b fa eb ae 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 20 48 89 f3 49 89 fd 48 bd 00
RSP: 0018:ffffc9000d670000 EFLAGS: 00010246
RAX: 1ffff1100235a4a5 RBX: ffff888011ad2508 RCX: ffff8880003c0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888037f01000
RBP: dffffc0000000000 R08: ffffffff8fa104f7 R09: 1ffffffff1f4209e
R10: dffffc0000000000 R11: ffffffff8a99b300 R12: ffffffff8a99b300
R13: ffff888037f01000 R14: ffff888011ad2500 R15: ffff888037f01578
FS:  000055557ab6d500(0000) GS:ffff88808d250000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000d66fff8 CR3: 0000000043172000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 clip_push+0x6dc/0x720 net/atm/clip.c:200
 clip_push+0x6dc/0x720 net/atm/clip.c:200
 clip_push+0x6dc/0x720 net/atm/clip.c:200
...
 clip_push+0x6dc/0x720 net/atm/clip.c:200
 clip_push+0x6dc/0x720 net/atm/clip.c:200
 clip_push+0x6dc/0x720 net/atm/clip.c:200
 vcc_destroy_socket net/atm/common.c:183 [inline]
 vcc_release+0x157/0x460 net/atm/common.c:205
 __sock_release net/socket.c:647 [inline]
 sock_close+0xc0/0x240 net/socket.c:1391
 __fput+0x449/0xa70 fs/file_table.c:465
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff31c98e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffb5aa1f78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000012747 RCX: 00007ff31c98e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007ff31cbb7ba0 R08: 0000000000000001 R09: 0000000db5aa226f
R10: 00007ff31c7ff030 R11: 0000000000000246 R12: 00007ff31cbb608c
R13: 00007ff31cbb6080 R14: ffffffffffffffff R15: 00007fffb5aa2090
 </TASK>
Modules linked in:

Fixes: 1da177e ("Linux-2.6.12-rc2")
Reported-by: syzbot+0c77cccd6b7cd917b35a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=2371d94d248d126c1eb1
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250704062416.1613927-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
atmarpd_dev_ops does not implement the send method, which may cause crash
as bellow.

BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: Oops: 0010 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5324 Comm: syz.0.0 Not tainted 6.15.0-rc6-syzkaller-00346-g5723cc3450bc #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc9000d3cf778 EFLAGS: 00010246
RAX: 1ffffffff1910dd1 RBX: 00000000000000c0 RCX: dffffc0000000000
RDX: ffffc9000dc82000 RSI: ffff88803e4c4640 RDI: ffff888052cd0000
RBP: ffffc9000d3cf8d0 R08: ffff888052c9143f R09: 1ffff1100a592287
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff92001a79f00
R13: ffff888052cd0000 R14: ffff88803e4c4640 R15: ffffffff8c886e88
FS:  00007fbc762566c0(0000) GS:ffff88808d6c2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000041f1b000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vcc_sendmsg+0xa10/0xc50 net/atm/common.c:644
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmmsg+0x227/0x430 net/socket.c:2709
 __do_sys_sendmmsg net/socket.c:2736 [inline]
 __se_sys_sendmmsg net/socket.c:2733 [inline]
 __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2733
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 1da177e ("Linux-2.6.12-rc2")
Reported-by: syzbot+e34e5e6b5eddb0014def@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/682f82d5.a70a0220.1765ec.0143.GAE@google.com/T
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250705085228.329202-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
alloc_tag_top_users() attempts to lock alloc_tag_cttype->mod_lock even
when the alloc_tag_cttype is not allocated because:

  1) alloc tagging is disabled because mem profiling is disabled
     (!alloc_tag_cttype)
  2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
  3) alloc tagging is enabled, but failed initialization
     (!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))

In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.

This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:

  Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
  CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G      D             6.16.0-rc2 #1 VOLUNTARY
  Tainted: [D]=DIE
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
  RIP: 0010:down_read_trylock+0xaa/0x3b0
  Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
  RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
  RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
  RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
  RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
  R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
  R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
  FS:  00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
  Call Trace:
   <TASK>
   codetag_trylock_module_list+0xd/0x20
   alloc_tag_top_users+0x369/0x4b0
   __show_mem+0x1cd/0x6e0
   warn_alloc+0x2b1/0x390
   __alloc_frozen_pages_noprof+0x12b9/0x21a0
   alloc_pages_mpol+0x135/0x3e0
   alloc_slab_page+0x82/0xe0
   new_slab+0x212/0x240
   ___slab_alloc+0x82a/0xe00
   </TASK>

As David Wang points out, this issue became easier to trigger after commit
780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init").

Before the commit, the issue occurred only when it failed to allocate and
initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called.  After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.

To properly determine whether alloc_tag_init() has been called and its
data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore.  If the variable is NULL or an
error value, it has not been properly initialized.  In such a case, just
skip and do not attempt to acquire the semaphore.

[harry.yoo@oracle.com: v3]
  Link: https://lkml.kernel.org/r/20250624072513.84219-1-harry.yoo@oracle.com
Link: https://lkml.kernel.org/r/20250620195305.1115151-1-harry.yoo@oracle.com
Fixes: 780138b ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d34 ("lib: add memory allocations report in show_mem()")
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202506181351.bba867dd-lkp@intel.com
Acked-by: Suren Baghdasaryan <surenb@google.com>
Tested-by: Raghavendra K T <raghavendra.kt@amd.com>
Cc: Casey Chen <cachen@purestorage.com>
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Yuanyuan Zhong <yzhong@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
There are cases when we try to pin a folio but discover that it has not
been faulted-in.  So, we try to allocate it in memfd_alloc_folio() but
there is a chance that we might encounter a fatal crash/failure
(VM_BUG_ON(!h->resv_huge_pages) in alloc_hugetlb_folio_reserve()) if there
are no active reservations at that instant.  This issue was reported by
syzbot:

kernel BUG at mm/hugetlb.c:2403!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5315 Comm: syz.0.0 Not tainted
6.13.0-rc5-syzkaller-00161-g63676eefb7a0 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:alloc_hugetlb_folio_reserve+0xbc/0xc0 mm/hugetlb.c:2403
Code: 1f eb 05 e8 56 18 a0 ff 48 c7 c7 40 56 61 8e e8 ba 21 cc 09 4c 89
f0 5b 41 5c 41 5e 41 5f 5d c3 cc cc cc cc e8 35 18 a0 ff 90 <0f> 0b 66
90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f
RSP: 0018:ffffc9000d3d77f8 EFLAGS: 00010087
RAX: ffffffff81ff6beb RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9000e51a000 RSI: 00000000000003ec RDI: 00000000000003ed
RBP: 1ffffffff34810d9 R08: ffffffff81ff6ba3 R09: 1ffffd4000093005
R10: dffffc0000000000 R11: fffff94000093006 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffea0000498000 R15: ffffffff9a4086c8
FS:  00007f77ac12e6c0(0000) GS:ffff88801fc00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f77ab54b170 CR3: 0000000040b70000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 memfd_alloc_folio+0x1bd/0x370 mm/memfd.c:88
 memfd_pin_folios+0xf10/0x1570 mm/gup.c:3750
 udmabuf_pin_folios drivers/dma-buf/udmabuf.c:346 [inline]
 udmabuf_create+0x70e/0x10c0 drivers/dma-buf/udmabuf.c:443
 udmabuf_ioctl_create drivers/dma-buf/udmabuf.c:495 [inline]
 udmabuf_ioctl+0x301/0x4e0 drivers/dma-buf/udmabuf.c:526
 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

Therefore, prevent the above crash by removing the VM_BUG_ON() as there is
no need to crash the system in this situation and instead we could just
fail the allocation request.

Furthermore, as described above, the specific situation where this happens
is when we try to pin memfd folios before they are faulted-in.  Although,
this is a valid thing to do, it is not the regular or the common use-case.
Let us consider the following scenarios:

1) hugetlbfs_file_mmap()
    memfd_alloc_folio()
    hugetlb_fault()

2) memfd_alloc_folio()
    hugetlbfs_file_mmap()
    hugetlb_fault()

3) hugetlbfs_file_mmap()
    hugetlb_fault()
        alloc_hugetlb_folio()

3) is the most common use-case where first a memfd is allocated followed
by mmap(), user writes/updates and then the relevant folios are pinned
(memfd_pin_folios()).  The BUG this patch is fixing occurs in 2) because
we try to pin the folios before hugetlbfs_file_mmap() is called.  So, in
this situation we try to allocate the folios before pinning them but since
we did not make any reservations, resv_huge_pages would be 0, leading to
this issue.

Link: https://lkml.kernel.org/r/20250626191116.1377761-1-vivek.kasireddy@intel.com
Fixes: 26a8ea8 ("mm/hugetlb: fix memfd_pin_folios resv_huge_pages leak")
Reported-by: syzbot+a504cb5bae4fe117ba94@syzkaller.appspotmail.com
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Closes: https://syzkaller.appspot.com/bug?extid=a504cb5bae4fe117ba94
Closes: https://lore.kernel.org/all/677928b5.050a0220.3b53b0.004d.GAE@google.com/T/
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Steve Sistare <steven.sistare@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
Patch series "mm/damon: fix divide by zero and its samples", v3.

This series includes fixes against damon and its samples to make it safer
when damon sample starting fails.

It includes the following changes.
- fix unexpected divide by zero crash for zero size regions
- fix bugs for damon samples in case of start failures


This patch (of 4):

The damon_sample_prcl_start() can fail so we must reset the "enable"
parameter to "false" again for proper rollback.

In such cases, setting Y to "enable" then N triggers the following crash
because damon sample start failed but the "enable" stays as Y.

  [ 2441.419649] damon_sample_prcl: start
  [ 2454.146817] damon_sample_prcl: stop
  [ 2454.146862] ------------[ cut here ]------------
  [ 2454.146865] kernel BUG at mm/slub.c:546!
  [ 2454.148183] Oops: invalid opcode: 0000 [#1] SMP NOPTI
  	...
  [ 2454.167555] Call Trace:
  [ 2454.167822]  <TASK>
  [ 2454.168061]  damon_destroy_ctx+0x78/0x140
  [ 2454.168454]  damon_sample_prcl_enable_store+0x8d/0xd0
  [ 2454.168932]  param_attr_store+0xa1/0x120
  [ 2454.169315]  module_attr_store+0x20/0x50
  [ 2454.169695]  sysfs_kf_write+0x72/0x90
  [ 2454.170065]  kernfs_fop_write_iter+0x150/0x1e0
  [ 2454.170491]  vfs_write+0x315/0x440
  [ 2454.170833]  ksys_write+0x69/0xf0
  [ 2454.171162]  __x64_sys_write+0x19/0x30
  [ 2454.171525]  x64_sys_call+0x18b2/0x2700
  [ 2454.171900]  do_syscall_64+0x7f/0x680
  [ 2454.172258]  ? exit_to_user_mode_loop+0xf6/0x180
  [ 2454.172694]  ? clear_bhb_loop+0x30/0x80
  [ 2454.173067]  ? clear_bhb_loop+0x30/0x80
  [ 2454.173439]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Link: https://lkml.kernel.org/r/20250702000205.1921-1-honggyu.kim@sk.com
Link: https://lkml.kernel.org/r/20250702000205.1921-2-honggyu.kim@sk.com
Fixes: 2aca254 ("samples/damon: introduce a skeleton of a smaple DAMON module for proactive reclamation")
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
The current implementation allows having zero size regions with no special
reasons, but damon_get_intervals_score() gets crashed by divide by zero
when the region size is zero.

  [   29.403950] Oops: divide error: 0000 [#1] SMP NOPTI

This patch fixes the bug, but does not disallow zero size regions to keep
the backward compatibility since disallowing zero size regions might be a
breaking change for some users.

In addition, the same crash can happen when intervals_goal.access_bp is
zero so this should be fixed in stable trees as well.

Link: https://lkml.kernel.org/r/20250702000205.1921-5-honggyu.kim@sk.com
Fixes: f04b0fe ("mm/damon/core: implement intervals auto-tuning")
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:

BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
 #0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
 #1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
 #2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
 #3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 torvalds#305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
 <TASK>
 dump_stack_lvl+0x53/0x70
 __might_resched+0x360/0x4e0
 do_global_cleanup+0x2f5/0x710
 process_one_work+0x7db/0x1970
 worker_thread+0x518/0xea0
 kthread+0x359/0x690
 ret_from_fork+0xf3/0x1b0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

That can be reproduced by:

  veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
  SIZE=$(blockdev --getsz /dev/vda)
  dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
  mount /dev/dm-0 /mnt -o ro
  echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
  [read files in /mnt]

Cc: stable@vger.kernel.org	# v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <wangshuai12@xiaomi.com>
Signed-off-by: Sheng Yong <shengyong1@xiaomi.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
syzbot reported weird splats [0][1] in cipso_v4_sock_setattr() while
freeing inet_sk(sk)->inet_opt.

The address was freed multiple times even though it was read-only memory.

cipso_v4_sock_setattr() did nothing wrong, and the root cause was type
confusion.

The cited commit made it possible to create smc_sock as an INET socket.

The issue is that struct smc_sock does not have struct inet_sock as the
first member but hijacks AF_INET and AF_INET6 sk_family, which confuses
various places.

In this case, inet_sock.inet_opt was actually smc_sock.clcsk_data_ready(),
which is an address of a function in the text segment.

  $ pahole -C inet_sock vmlinux
  struct inet_sock {
  ...
          struct ip_options_rcu *    inet_opt;             /*   784     8 */

  $ pahole -C smc_sock vmlinux
  struct smc_sock {
  ...
          void                       (*clcsk_data_ready)(struct sock *); /*   784     8 */

The same issue for another field was reported before. [2][3]

At that time, an ugly hack was suggested [4], but it makes both INET
and SMC code error-prone and hard to change.

Also, yet another variant was fixed by a hacky commit 98d4435
("net/smc: prevent NULL pointer dereference in txopt_get").

Instead of papering over the root cause by such hacks, we should not
allow non-INET socket to reuse the INET infra.

Let's add inet_sock as the first member of smc_sock.

[0]:
kvfree_call_rcu(): Double-freed call. rcu_head 000000006921da73
WARNING: CPU: 0 PID: 6718 at mm/slab_common.c:1956 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
Modules linked in:
CPU: 0 UID: 0 PID: 6718 Comm: syz.0.17 Tainted: G        W           6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
lr : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955
sp : ffff8000a03a7730
x29: ffff8000a03a7730 x28: 00000000fffffff5 x27: 1fffe000184823d3
x26: dfff800000000000 x25: ffff0000c2411e9e x24: ffff0000dd88da00
x23: ffff8000891ac9a0 x22: 00000000ffffffea x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: ffff80008afc2480 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ae642c8 x15: ffff700011ede14c
x14: 1ffff00011ede14c x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011ede14c x10: 0000000000ff0100 x9 : 5fa3c1ffaf0ff000
x8 : 5fa3c1ffaf0ff000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a03a7078 x4 : ffff80008f766c20 x3 : ffff80008054d360
x2 : 0000000000000000 x1 : 0000000000000201 x0 : 0000000000000000
Call trace:
 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

[1]:
Unable to handle kernel write to read-only memory at virtual address ffff8000891ac9a8
KASAN: probably user-memory-access in range [0x0000000448d64d40-0x0000000448d64d47]
Mem abort info:
  ESR = 0x000000009600004e
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x0e: level 2 permission fault
Data abort info:
  ISV = 0, ISS = 0x0000004e, ISS2 = 0x00000000
  CM = 0, WnR = 1, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000207144000
[ffff8000891ac9a8] pgd=0000000000000000, p4d=100000020f950003, pud=100000020f951003, pmd=0040000201000781
Internal error: Oops: 000000009600004e [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 6946 Comm: syz.0.69 Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1971
lr : add_ptr_to_bulk_krc_lock mm/slab_common.c:1838 [inline]
lr : kvfree_call_rcu+0xfc/0x3f0 mm/slab_common.c:1963
sp : ffff8000a28a7730
x29: ffff8000a28a7730 x28: 00000000fffffff5 x27: 1fffe00018b09bb3
x26: 0000000000000001 x25: ffff80008f66e000 x24: ffff00019beaf498
x23: ffff00019beaf4c0 x22: 0000000000000000 x21: ffff8000891ac9a0
x20: ffff8000891ac9a0 x19: 0000000000000000 x18: 00000000ffffffff
x17: ffff800093363000 x16: ffff80008052c6e4 x15: ffff700014514ecc
x14: 1ffff00014514ecc x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700014514ecc x10: 0000000000000001 x9 : 0000000000000001
x8 : ffff00019beaf7b4 x7 : ffff800080a94154 x6 : 0000000000000000
x5 : ffff8000935efa60 x4 : 0000000000000008 x3 : ffff80008052c7fc
x2 : 0000000000000001 x1 : ffff8000891ac9a0 x0 : 0000000000000001
Call trace:
 kvfree_call_rcu+0x31c/0x3f0 mm/slab_common.c:1967 (P)
 cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914
 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000
 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581
 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912
 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706
 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295
 vfs_setxattr+0x158/0x2ac fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 file_setxattr+0x1b8/0x294 fs/xattr.c:646
 path_setxattrat+0x2ac/0x320 fs/xattr.c:711
 __do_sys_fsetxattr fs/xattr.c:761 [inline]
 __se_sys_fsetxattr fs/xattr.c:758 [inline]
 __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: aa1f03e2 52800023 97ee1e8d b4000195 (f90006b4)

Fixes: d25a92c ("net/smc: Introduce IPPROTO_SMC")
Reported-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686d9b50.050a0220.1ffab7.0020.GAE@google.com/
Tested-by: syzbot+40bf00346c3fe40f90f2@syzkaller.appspotmail.com
Reported-by: syzbot+f22031fad6cbe52c70e7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/686da0f3.050a0220.1ffab7.0022.GAE@google.com/
Reported-by: syzbot+271fed3ed6f24600c364@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=271fed3ed6f24600c364 # [2]
Link: https://lore.kernel.org/netdev/99f284be-bf1d-4bc4-a629-77b268522fff@huawei.com/ # [3]
Link: https://lore.kernel.org/netdev/20250331081003.1503211-1-wangliang74@huawei.com/ # [4]
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20250711060808.2977529-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
The conversion from compiler assisted indexing to manual
indexing wasn't done correctly. The array is still made
up of __le16 elements so multiplying the outer index by
the element size is not what we want. Fix it up.

This causes the kernel to oops when trying to transfer any
significant amount of data over wifi:

BUG: unable to handle page fault for address: ffffc900009f5282
PGD 100000067 P4D 100000067 PUD 1000fb067 PMD 102e82067 PTE 0
Oops: Oops: 0002 [#1] SMP
CPU: 1 UID: 0 PID: 99 Comm: kworker/u8:3 Not tainted 6.15.0-rc2-cl-bisect3-00604-g6204d5130a64-dirty torvalds#78 PREEMPT
Hardware name: Dell Inc. Latitude E5400                  /0D695C, BIOS A19 06/13/2013
Workqueue: events_unbound cfg80211_wiphy_work [cfg80211]
RIP: 0010:iwl_trans_pcie_tx+0x4dd/0xe60 [iwlwifi]
Code: 00 00 66 81 fa ff 0f 0f 87 42 09 00 00 3d ff 00 00 00 0f 8f 37 09 00 00 41 c1 e0 0c 41 09 d0 48 8d 14 b6 48 c1 e2 07 48 01 ca <66> 44 89 04 57 48 8d 0c 12 83 f8 3f 0f 8e 84 01 00 00 41 8b 85 80
RSP: 0018:ffffc900001c3b50 EFLAGS: 00010206
RAX: 00000000000000c1 RBX: ffff88810b180028 RCX: 00000000000000c1
RDX: 0000000000002141 RSI: 000000000000000d RDI: ffffc900009f1000
RBP: 0000000000000002 R08: 0000000000000025 R09: ffffffffa050fa60
R10: 00000000fbdbf4bc R11: 0000000000000082 R12: ffff88810e5ade40
R13: ffff88810af81588 R14: 000000000000001a R15: ffff888100dfe0c8
FS:  0000000000000000(0000) GS:ffff8881998c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900009f5282 CR3: 0000000001e39000 CR4: 00000000000426f0
Call Trace:
 <TASK>
 ? rcu_is_watching+0xd/0x40
 ? __iwl_dbg+0xb1/0xe0 [iwlwifi]
 iwlagn_tx_skb+0x8e2/0xcb0 [iwldvm]
 iwlagn_mac_tx+0x18/0x30 [iwldvm]
 ieee80211_handle_wake_tx_queue+0x6c/0xc0 [mac80211]
 ieee80211_agg_start_txq+0x140/0x2e0 [mac80211]
 ieee80211_agg_tx_operational+0x126/0x210 [mac80211]
 ieee80211_process_addba_resp+0x27b/0x2a0 [mac80211]
 ieee80211_iface_work+0x4bd/0x4d0 [mac80211]
 ? _raw_spin_unlock_irq+0x1f/0x40
 cfg80211_wiphy_work+0x117/0x1f0 [cfg80211]
 process_one_work+0x1ee/0x570
 worker_thread+0x1c5/0x3b0
 ? bh_worker+0x240/0x240
 kthread+0x110/0x220
 ? kthread_queue_delayed_work+0x90/0x90
 ret_from_fork+0x28/0x40
 ? kthread_queue_delayed_work+0x90/0x90
 ret_from_fork_asm+0x11/0x20
 </TASK>
Modules linked in: ctr aes_generic ccm sch_fq_codel bnep xt_tcpudp xt_multiport xt_state iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 ip_tables x_tables btusb btrtl btintel btbcm bluetooth ecdh_generic ecc libaes hid_generic usbhid hid binfmt_misc joydev mousedev snd_hda_codec_hdmi iwldvm snd_hda_codec_idt snd_hda_codec_generic mac80211 coretemp iTCO_wdt watchdog kvm_intel i2c_dev snd_hda_intel libarc4 kvm snd_intel_dspcfg sdhci_pci sdhci_uhs2 snd_hda_codec iwlwifi sdhci irqbypass cqhci snd_hwdep snd_hda_core cfg80211 firewire_ohci mmc_core psmouse snd_pcm i2c_i801 firewire_core pcspkr led_class uhci_hcd i2c_smbus tg3 crc_itu_t iosf_mbi snd_timer rfkill libphy ehci_pci snd ehci_hcd lpc_ich mfd_core usbcore video intel_agp usb_common soundcore intel_gtt evdev agpgart parport_pc wmi parport backlight
CR2: ffffc900009f5282
---[ end trace 0000000000000000 ]---
RIP: 0010:iwl_trans_pcie_tx+0x4dd/0xe60 [iwlwifi]
Code: 00 00 66 81 fa ff 0f 0f 87 42 09 00 00 3d ff 00 00 00 0f 8f 37 09 00 00 41 c1 e0 0c 41 09 d0 48 8d 14 b6 48 c1 e2 07 48 01 ca <66> 44 89 04 57 48 8d 0c 12 83 f8 3f 0f 8e 84 01 00 00 41 8b 85 80
RSP: 0018:ffffc900001c3b50 EFLAGS: 00010206
RAX: 00000000000000c1 RBX: ffff88810b180028 RCX: 00000000000000c1
RDX: 0000000000002141 RSI: 000000000000000d RDI: ffffc900009f1000
RBP: 0000000000000002 R08: 0000000000000025 R09: ffffffffa050fa60
R10: 00000000fbdbf4bc R11: 0000000000000082 R12: ffff88810e5ade40
R13: ffff88810af81588 R14: 000000000000001a R15: ffff888100dfe0c8
FS:  0000000000000000(0000) GS:ffff8881998c3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc900009f5282 CR3: 0000000001e39000 CR4: 00000000000426f0
Kernel panic - not syncing: Fatal exception in interrupt
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Cc: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Fixes: 6204d51 ("wifi: iwlwifi: use bc entries instead of bc table also for pre-ax210")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20250711205744.28723-1-ville.syrjala@linux.intel.com
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
boryas pushed a commit that referenced this pull request Jul 23, 2025
This reverts commit 7796c97.

This patch broke Dragonboard 845c (sdm845). I see:

    Unexpected kernel BRK exception at EL1
    Internal error: BRK handler: 00000000f20003e8 [#1]  SMP
    pc : qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom]
    lr : snd_soc_dai_set_channel_map+0x34/0x78
    Call trace:
     qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] (P)
     sdm845_dai_init+0x18c/0x2e0 [snd_soc_sdm845]
     snd_soc_link_init+0x28/0x6c
     snd_soc_bind_card+0x5f4/0xb0c
     snd_soc_register_card+0x148/0x1a4
     devm_snd_soc_register_card+0x50/0xb0
     sdm845_snd_platform_probe+0x124/0x148 [snd_soc_sdm845]
     platform_probe+0x6c/0xd0
     really_probe+0xc0/0x2a4
     __driver_probe_device+0x7c/0x130
     driver_probe_device+0x40/0x118
     __device_attach_driver+0xc4/0x108
     bus_for_each_drv+0x8c/0xf0
     __device_attach+0xa4/0x198
     device_initial_probe+0x18/0x28
     bus_probe_device+0xb8/0xbc
     deferred_probe_work_func+0xac/0xfc
     process_one_work+0x244/0x658
     worker_thread+0x1b4/0x360
     kthread+0x148/0x228
     ret_from_fork+0x10/0x20
    Kernel panic - not syncing: BRK handler: Fatal exception

Dan has also reported following issues with the original patch
https://lore.kernel.org/all/33fe8fe7-719a-405a-9ed2-d9f816ce1d57@sabinyo.mountain/

Bug #1:
The zeroeth element of ctrl->pconfig[] is supposed to be unused.  We
start counting at 1.  However this code sets ctrl->pconfig[0].ch_mask = 128.

Bug #2:
There are SLIM_MAX_TX_PORTS (16) elements in tx_ch[] array but only
QCOM_SDW_MAX_PORTS + 1 (15) in the ctrl->pconfig[] array so it corrupts
memory like Yongqin Liu pointed out.

Bug 3:
Like Jie Gan pointed out, it erases all the tx information with the rx
information.

Cc: stable@vger.kernel.org # v6.15+
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Acked-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250709174949.8541-1-amit.pundir@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
When device reset is triggered by feature changes such as toggling Rx
VLAN offload, wx->do_reset() is called to reinitialize Rx rings. The
hardware descriptor ring may retain stale values from previous sessions.
And only set the length to 0 in rx_desc[0] would result in building
malformed SKBs. Fix it to ensure a clean slate after device reset.

[  549.186435] [     C16] ------------[ cut here ]------------
[  549.186457] [     C16] kernel BUG at net/core/skbuff.c:2814!
[  549.186468] [     C16] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[  549.186472] [     C16] CPU: 16 UID: 0 PID: 0 Comm: swapper/16 Kdump: loaded Not tainted 6.16.0-rc4+ torvalds#23 PREEMPT(voluntary)
[  549.186476] [     C16] Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024
[  549.186478] [     C16] RIP: 0010:__pskb_pull_tail+0x3ff/0x510
[  549.186484] [     C16] Code: 06 f0 ff 4f 34 74 7b 4d 8b 8c 24 c8 00 00 00 45 8b 84 24 c0 00 00 00 e9 c8 fd ff ff 48 c7 44 24 08 00 00 00 00 e9 5e fe ff ff <0f> 0b 31 c0 e9 23 90 5b ff 41 f7 c6 ff 0f 00 00 75 bf 49 8b 06 a8
[  549.186487] [     C16] RSP: 0018:ffffb391c0640d70 EFLAGS: 00010282
[  549.186490] [     C16] RAX: 00000000fffffff2 RBX: ffff8fe7e4d40200 RCX: 00000000fffffff2
[  549.186492] [     C16] RDX: ffff8fe7c3a4bf8e RSI: 0000000000000180 RDI: ffff8fe7c3a4bf40
[  549.186494] [     C16] RBP: ffffb391c0640da8 R08: ffff8fe7c3a4c0c0 R09: 000000000000000e
[  549.186496] [     C16] R10: ffffb391c0640d88 R11: 000000000000000e R12: ffff8fe7e4d40200
[  549.186497] [     C16] R13: 00000000fffffff2 R14: ffff8fe7fa01a000 R15: 00000000fffffff2
[  549.186499] [     C16] FS:  0000000000000000(0000) GS:ffff8fef5ae40000(0000) knlGS:0000000000000000
[  549.186502] [     C16] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  549.186503] [     C16] CR2: 00007f77d81d6000 CR3: 000000051a032000 CR4: 0000000000750ef0
[  549.186505] [     C16] PKRU: 55555554
[  549.186507] [     C16] Call Trace:
[  549.186510] [     C16]  <IRQ>
[  549.186513] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186517] [     C16]  __skb_pad+0xc7/0xf0
[  549.186523] [     C16]  wx_clean_rx_irq+0x355/0x3b0 [libwx]
[  549.186533] [     C16]  wx_poll+0x92/0x120 [libwx]
[  549.186540] [     C16]  __napi_poll+0x28/0x190
[  549.186544] [     C16]  net_rx_action+0x301/0x3f0
[  549.186548] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186551] [     C16]  ? __raw_spin_lock_irqsave+0x1e/0x50
[  549.186554] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186557] [     C16]  ? wake_up_nohz_cpu+0x35/0x160
[  549.186559] [     C16]  ? srso_alias_return_thunk+0x5/0xfbef5
[  549.186563] [     C16]  handle_softirqs+0xf9/0x2c0
[  549.186568] [     C16]  __irq_exit_rcu+0xc7/0x130
[  549.186572] [     C16]  common_interrupt+0xb8/0xd0
[  549.186576] [     C16]  </IRQ>
[  549.186577] [     C16]  <TASK>
[  549.186579] [     C16]  asm_common_interrupt+0x22/0x40
[  549.186582] [     C16] RIP: 0010:cpuidle_enter_state+0xc2/0x420
[  549.186585] [     C16] Code: 00 00 e8 11 0e 5e ff e8 ac f0 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 0d ed 5c ff 45 84 ff 0f 85 40 02 00 00 fb 0f 1f 44 00 00 <45> 85 f6 0f 88 84 01 00 00 49 63 d6 48 8d 04 52 48 8d 04 82 49 8d
[  549.186587] [     C16] RSP: 0018:ffffb391c0277e78 EFLAGS: 00000246
[  549.186590] [     C16] RAX: ffff8fef5ae40000 RBX: 0000000000000003 RCX: 0000000000000000
[  549.186591] [     C16] RDX: 0000007fde0faac5 RSI: ffffffff826e53f6 RDI: ffffffff826fa9b3
[  549.186593] [     C16] RBP: ffff8fe7c3a20800 R08: 0000000000000002 R09: 0000000000000000
[  549.186595] [     C16] R10: 0000000000000000 R11: 000000000000ffff R12: ffffffff82ed7a40
[  549.186596] [     C16] R13: 0000007fde0faac5 R14: 0000000000000003 R15: 0000000000000000
[  549.186601] [     C16]  ? cpuidle_enter_state+0xb3/0x420
[  549.186605] [     C16]  cpuidle_enter+0x29/0x40
[  549.186609] [     C16]  cpuidle_idle_call+0xfd/0x170
[  549.186613] [     C16]  do_idle+0x7a/0xc0
[  549.186616] [     C16]  cpu_startup_entry+0x25/0x30
[  549.186618] [     C16]  start_secondary+0x117/0x140
[  549.186623] [     C16]  common_startup_64+0x13e/0x148
[  549.186628] [     C16]  </TASK>

Fixes: 3c47e8a ("net: libwx: Support to receive packets in NAPI")
Cc: stable@vger.kernel.org
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250714024755.17512-4-jiawenwu@trustnetic.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
… runtime

Assuming the "rx-vlan-filter" feature is enabled on a net device, the
8021q module will automatically add or remove VLAN 0 when the net device
is put administratively up or down, respectively. There are a couple of
problems with the above scheme.

The first problem is a memory leak that can happen if the "rx-vlan-filter"
feature is disabled while the device is running:

 # ip link add bond1 up type bond mode 0
 # ethtool -K bond1 rx-vlan-filter off
 # ip link del dev bond1

When the device is put administratively down the "rx-vlan-filter"
feature is disabled, so the 8021q module will not remove VLAN 0 and the
memory will be leaked [1].

Another problem that can happen is that the kernel can automatically
delete VLAN 0 when the device is put administratively down despite not
adding it when the device was put administratively up since during that
time the "rx-vlan-filter" feature was disabled. null-ptr-unref or
bug_on[2] will be triggered by unregister_vlan_dev() for refcount
imbalance if toggling filtering during runtime:

$ ip link add bond0 type bond mode 0
$ ip link add link bond0 name vlan0 type vlan id 0 protocol 802.1q
$ ethtool -K bond0 rx-vlan-filter off
$ ifconfig bond0 up
$ ethtool -K bond0 rx-vlan-filter on
$ ifconfig bond0 down
$ ip link del vlan0

Root cause is as below:
step1: add vlan0 for real_dev, such as bond, team.
register_vlan_dev
    vlan_vid_add(real_dev,htons(ETH_P_8021Q),0) //refcnt=1
step2: disable vlan filter feature and enable real_dev
step3: change filter from 0 to 1
vlan_device_event
    vlan_filter_push_vids
        ndo_vlan_rx_add_vid //No refcnt added to real_dev vlan0
step4: real_dev down
vlan_device_event
    vlan_vid_del(dev, htons(ETH_P_8021Q), 0); //refcnt=0
        vlan_info_rcu_free //free vlan0
step5: delete vlan0
unregister_vlan_dev
    BUG_ON(!vlan_info); //vlan_info is null

Fix both problems by noting in the VLAN info whether VLAN 0 was
automatically added upon NETDEV_UP and based on that decide whether it
should be deleted upon NETDEV_DOWN, regardless of the state of the
"rx-vlan-filter" feature.

[1]
unreferenced object 0xffff8880068e3100 (size 256):
  comm "ip", pid 384, jiffies 4296130254
  hex dump (first 32 bytes):
    00 20 30 0d 80 88 ff ff 00 00 00 00 00 00 00 00  . 0.............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 81ce31fa):
    __kmalloc_cache_noprof+0x2b5/0x340
    vlan_vid_add+0x434/0x940
    vlan_device_event.cold+0x75/0xa8
    notifier_call_chain+0xca/0x150
    __dev_notify_flags+0xe3/0x250
    rtnl_configure_link+0x193/0x260
    rtnl_newlink_create+0x383/0x8e0
    __rtnl_newlink+0x22c/0xa40
    rtnl_newlink+0x627/0xb00
    rtnetlink_rcv_msg+0x6fb/0xb70
    netlink_rcv_skb+0x11f/0x350
    netlink_unicast+0x426/0x710
    netlink_sendmsg+0x75a/0xc20
    __sock_sendmsg+0xc1/0x150
    ____sys_sendmsg+0x5aa/0x7b0
    ___sys_sendmsg+0xfc/0x180

[2]
kernel BUG at net/8021q/vlan.c:99!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 382 Comm: ip Not tainted 6.16.0-rc3 torvalds#61 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:unregister_vlan_dev (net/8021q/vlan.c:99 (discriminator 1))
RSP: 0018:ffff88810badf310 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88810da84000 RCX: ffffffffb47ceb9a
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88810e8b43c8
RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff6cefe80
R10: ffffffffb677f407 R11: ffff88810badf3c0 R12: ffff88810e8b4000
R13: 0000000000000000 R14: ffff88810642a5c0 R15: 000000000000017e
FS:  00007f1ff68c20c0(0000) GS:ffff888163a24000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1ff5dad240 CR3: 0000000107e56000 CR4: 00000000000006f0
Call Trace:
 <TASK>
rtnl_dellink (net/core/rtnetlink.c:3511 net/core/rtnetlink.c:3553)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6945)
netlink_rcv_skb (net/netlink/af_netlink.c:2535)
netlink_unicast (net/netlink/af_netlink.c:1314 net/netlink/af_netlink.c:1339)
netlink_sendmsg (net/netlink/af_netlink.c:1883)
____sys_sendmsg (net/socket.c:712 net/socket.c:727 net/socket.c:2566)
___sys_sendmsg (net/socket.c:2622)
__sys_sendmsg (net/socket.c:2652)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)

Fixes: ad1afb0 ("vlan_dev: VLAN 0 should be treated as "no vlan tag" (802.1p packet)")
Reported-by: syzbot+a8b046e462915c65b10b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a8b046e462915c65b10b
Suggested-by: Ido Schimmel <idosch@idosch.org>
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250716034504.2285203-2-dongchenchen2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
We have observed kernel panics when using timerlat with stack saving,
with the following dmesg output:

memcpy: detected buffer overflow: 88 byte write of buffer size 0
WARNING: CPU: 2 PID: 8153 at lib/string_helpers.c:1032 __fortify_report+0x55/0xa0
CPU: 2 UID: 0 PID: 8153 Comm: timerlatu/2 Kdump: loaded Not tainted 6.15.3-200.fc42.x86_64 #1 PREEMPT(lazy)
Call Trace:
 <TASK>
 ? trace_buffer_lock_reserve+0x2a/0x60
 __fortify_panic+0xd/0xf
 __timerlat_dump_stack.cold+0xd/0xd
 timerlat_dump_stack.part.0+0x47/0x80
 timerlat_fd_read+0x36d/0x390
 vfs_read+0xe2/0x390
 ? syscall_exit_to_user_mode+0x1d5/0x210
 ksys_read+0x73/0xe0
 do_syscall_64+0x7b/0x160
 ? exc_page_fault+0x7e/0x1a0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

__timerlat_dump_stack() constructs the ftrace stack entry like this:

struct stack_entry *entry;
...
memcpy(&entry->caller, fstack->calls, size);
entry->size = fstack->nr_entries;

Since commit e7186af ("tracing: Add back FORTIFY_SOURCE logic to
kernel_stack event structure"), struct stack_entry marks its caller
field with __counted_by(size). At the time of the memcpy, entry->size
contains garbage from the ringbuffer, which under some circumstances is
zero, triggering a kernel panic by buffer overflow.

Populate the size field before the memcpy so that the out-of-bounds
check knows the correct size. This is analogous to
__ftrace_trace_stack().

Cc: stable@vger.kernel.org
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Attila Fazekas <afazekas@redhat.com>
Link: https://lore.kernel.org/20250716143601.7313-1-tglozar@redhat.com
Fixes: e7186af ("tracing: Add back FORTIFY_SOURCE logic to kernel_stack event structure")
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
boryas pushed a commit that referenced this pull request Jul 23, 2025
There is a potential deadlock that can happen in
try_release_subpage_extent_buffer because the irq-safe
xarray spin lock fs_info->buffer_tree is being
acquired before the irq-unsafe eb->refs_lock.

This leads to the potential race:
// T1 (random eb->refs user)                  // T2 (release folio)

spin_lock(&eb->refs_lock);
// interrupt
end_bbio_meta_write()
  btrfs_meta_folio_clear_writeback()
                                              btree_release_folio()
                                                folio_test_writeback() //false
                                                try_release_extent_buffer()
                                                  try_release_subpage_extent_buffer()
                                                    xa_lock_irq(&fs_info->buffer_tree)
                                                    spin_lock(&eb->refs_lock); // blocked; held by T1
  buffer_tree_clear_mark()
    xas_lock_irqsave() // blocked; held by T2

I believe that the spin lock can safely be replaced by an rcu_read_lock.
The xa_for_each loop does not need the spin lock as it's already
internally protected by the rcu_read_lock. The extent buffer
is also protected by the rcu_read_lock so it won't be freed before we
take the eb->refs_lock and check the ref count.

The rcu_read_lock is taken and released every iteration, just like the
spin lock, which means we're not protected against concurrent
insertions into the xarray. This is fine because we rely on
folio->private to detect if there are any eb's remaining in the folio.

There is already some precedent for this with find_extent_buffer_nolock,
which loads an extent buffer from the xarray with only rcu_read_lock.

lockdep warning:

            =====================================================
            WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
            6.16.0-0_fbk701_debug_rc0_123_g4c06e63b9203 #1 Tainted: G
E    N
            -----------------------------------------------------
            kswapd0/66 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
            ffff000011ffd600 (&eb->refs_lock){+.+.}-{3:3}, at:
try_release_extent_buffer+0x18c/0x560

and this task is already holding:
            ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at:
try_release_extent_buffer+0x13c/0x560
            which would create a new lock dependency:
             (&buffer_xa_class){-.-.}-{3:3} ->
(&eb->refs_lock){+.+.}-{3:3}

but this new dependency connects a HARDIRQ-irq-safe lock:
             (&buffer_xa_class){-.-.}-{3:3}

... which became HARDIRQ-irq-safe at:
              lock_acquire+0x178/0x358
              _raw_spin_lock_irqsave+0x60/0x88
              buffer_tree_clear_mark+0xc4/0x160
              end_bbio_meta_write+0x238/0x398
              btrfs_bio_end_io+0x1f8/0x330
              btrfs_orig_write_end_io+0x1c4/0x2c0
              bio_endio+0x63c/0x678
              blk_update_request+0x1c4/0xa00
              blk_mq_end_request+0x54/0x88
              virtblk_request_done+0x124/0x1d0
              blk_mq_complete_request+0x84/0xa0
              virtblk_done+0x130/0x238
              vring_interrupt+0x130/0x288
              __handle_irq_event_percpu+0x1e8/0x708
              handle_irq_event+0x98/0x1b0
              handle_fasteoi_irq+0x264/0x7c0
              generic_handle_domain_irq+0xa4/0x108
              gic_handle_irq+0x7c/0x1a0
              do_interrupt_handler+0xe4/0x148
              el1_interrupt+0x30/0x50
              el1h_64_irq_handler+0x14/0x20
              el1h_64_irq+0x6c/0x70
              _raw_spin_unlock_irq+0x38/0x70
              __run_timer_base+0xdc/0x5e0
              run_timer_softirq+0xa0/0x138
              handle_softirqs.llvm.13542289750107964195+0x32c/0xbd0
              ____do_softirq.llvm.17674514681856217165+0x18/0x28
              call_on_irq_stack+0x24/0x30
              __irq_exit_rcu+0x164/0x430
              irq_exit_rcu+0x18/0x88
              el1_interrupt+0x34/0x50
              el1h_64_irq_handler+0x14/0x20
              el1h_64_irq+0x6c/0x70
              arch_local_irq_enable+0x4/0x8
              do_idle+0x1a0/0x3b8
              cpu_startup_entry+0x60/0x80
              rest_init+0x204/0x228
              start_kernel+0x394/0x3f0
              __primary_switched+0x8c/0x8958

to a HARDIRQ-irq-unsafe lock:
             (&eb->refs_lock){+.+.}-{3:3}

... which became HARDIRQ-irq-unsafe at:
            ...
              lock_acquire+0x178/0x358
              _raw_spin_lock+0x4c/0x68
              free_extent_buffer_stale+0x2c/0x170
              btrfs_read_sys_array+0x1b0/0x338
              open_ctree+0xeb0/0x1df8
              btrfs_get_tree+0xb60/0x1110
              vfs_get_tree+0x8c/0x250
              fc_mount+0x20/0x98
              btrfs_get_tree+0x4a4/0x1110
              vfs_get_tree+0x8c/0x250
              do_new_mount+0x1e0/0x6c0
              path_mount+0x4ec/0xa58
              __arm64_sys_mount+0x370/0x490
              invoke_syscall+0x6c/0x208
              el0_svc_common+0x14c/0x1b8
              do_el0_svc+0x4c/0x60
              el0_svc+0x4c/0x160
              el0t_64_sync_handler+0x70/0x100
              el0t_64_sync+0x168/0x170

other info that might help us debug this:
             Possible interrupt unsafe locking scenario:
                   CPU0                    CPU1
                   ----                    ----
              lock(&eb->refs_lock);
                                           local_irq_disable();
                                           lock(&buffer_xa_class);
                                           lock(&eb->refs_lock);
              <Interrupt>
                lock(&buffer_xa_class);

  *** DEADLOCK ***
            2 locks held by kswapd0/66:
             #0: ffff800085506e40 (fs_reclaim){+.+.}-{0:0}, at:
balance_pgdat+0xe8/0xe50
             #1: ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at:
try_release_extent_buffer+0x13c/0x560

Link: https://www.kernel.org/doc/Documentation/locking/lockdep-design.rst#:~:text=Multi%2Dlock%20dependency%20rules%3A
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Fixes: 19d7f65 ("btrfs: convert the buffer_radix to an xarray")
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