[BUG]
There is a syzbot crash, triggered by the ASSERT() during subvolume
creation:

 assertion failed: !anon_dev, in fs/btrfs/disk-io.c:1319
 ------------[ cut here ]------------
 kernel BUG at fs/btrfs/disk-io.c:1319!
 invalid opcode: 0000 [#1] PREEMPT SMP KASAN
 RIP: 0010:btrfs_get_root_ref.part.0+0x9aa/0xa60
  <TASK>
  btrfs_get_new_fs_root+0xd3/0xf0
  create_subvol+0xd02/0x1650
  btrfs_mksubvol+0xe95/0x12b0
  __btrfs_ioctl_snap_create+0x2f9/0x4f0
  btrfs_ioctl_snap_create+0x16b/0x200
  btrfs_ioctl+0x35f0/0x5cf0
  __x64_sys_ioctl+0x19d/0x210
  do_syscall_64+0x3f/0xe0
  entry_SYSCALL_64_after_hwframe+0x63/0x6b
 ---[ end trace 0000000000000000 ]---

[CAUSE]
During create_subvol(), after inserting root item for the newly created
subvolume, we would trigger btrfs_get_new_fs_root() to get the
btrfs_root of that subvolume.

The idea here is, we have preallocated an anonymous device number for
the subvolume, thus we can assign it to the new subvolume.

But there is really nothing preventing things like backref walk to read
the new subvolume.
If that happens before we call btrfs_get_new_fs_root(), the subvolume
would be read out, with a new anonymous device number assigned already.

In that case, we would trigger ASSERT(), as we really expect no one to
read out that subvolume (which is not yet accessible from the fs).
But things like backref walk is still possible to trigger the read on
the subvolume.

Thus our assumption on the ASSERT() is not correct in the first place.

[FIX]
Fix it by removing the ASSERT(), and just free the @anon_dev, reset it
to 0, and continue.

If the subvolume tree is read out by something else, it should have
already get a new anon_dev assigned thus we only need to free the
preallocated one.

Reported-by: Chenyuan Yang <chenyuan0y@gmail.com>
Fixes: 2dfb1e4 ("btrfs: preallocate anon block device at first phase of snapshot creation")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

…_locked

The SEV platform device can be shutdown with a null psp_master,
e.g., using DEBUG_TEST_DRIVER_REMOVE.  Found using KASAN:

[  137.148210] ccp 0000:23:00.1: enabling device (0000 -> 0002)
[  137.162647] ccp 0000:23:00.1: no command queues available
[  137.170598] ccp 0000:23:00.1: sev enabled
[  137.174645] ccp 0000:23:00.1: psp enabled
[  137.178890] general protection fault, probably for non-canonical address 0xdffffc000000001e: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN NOPTI
[  137.182693] KASAN: null-ptr-deref in range [0x00000000000000f0-0x00000000000000f7]
[  137.182693] CPU: 93 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc1+ torvalds#311
[  137.182693] RIP: 0010:__sev_platform_shutdown_locked+0x51/0x180
[  137.182693] Code: 08 80 3c 08 00 0f 85 0e 01 00 00 48 8b 1d 67 b6 01 08 48 b8 00 00 00 00 00 fc ff df 48 8d bb f0 00 00 00 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 fe 00 00 00 48 8b 9b f0 00 00 00 48 85 db 74 2c
[  137.182693] RSP: 0018:ffffc900000cf9b0 EFLAGS: 00010216
[  137.182693] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 000000000000001e
[  137.182693] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 00000000000000f0
[  137.182693] RBP: ffffc900000cf9c8 R08: 0000000000000000 R09: fffffbfff58f5a66
[  137.182693] R10: ffffc900000cf9c8 R11: ffffffffac7ad32f R12: ffff8881e5052c28
[  137.182693] R13: ffff8881e5052c28 R14: ffff8881758e43e8 R15: ffffffffac64abf8
[  137.182693] FS:  0000000000000000(0000) GS:ffff889de7000000(0000) knlGS:0000000000000000
[  137.182693] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  137.182693] CR2: 0000000000000000 CR3: 0000001cf7c7e000 CR4: 0000000000350ef0
[  137.182693] Call Trace:
[  137.182693]  <TASK>
[  137.182693]  ? show_regs+0x6c/0x80
[  137.182693]  ? __die_body+0x24/0x70
[  137.182693]  ? die_addr+0x4b/0x80
[  137.182693]  ? exc_general_protection+0x126/0x230
[  137.182693]  ? asm_exc_general_protection+0x2b/0x30
[  137.182693]  ? __sev_platform_shutdown_locked+0x51/0x180
[  137.182693]  sev_firmware_shutdown.isra.0+0x1e/0x80
[  137.182693]  sev_dev_destroy+0x49/0x100
[  137.182693]  psp_dev_destroy+0x47/0xb0
[  137.182693]  sp_destroy+0xbb/0x240
[  137.182693]  sp_pci_remove+0x45/0x60
[  137.182693]  pci_device_remove+0xaa/0x1d0
[  137.182693]  device_remove+0xc7/0x170
[  137.182693]  really_probe+0x374/0xbe0
[  137.182693]  ? srso_return_thunk+0x5/0x5f
[  137.182693]  __driver_probe_device+0x199/0x460
[  137.182693]  driver_probe_device+0x4e/0xd0
[  137.182693]  __driver_attach+0x191/0x3d0
[  137.182693]  ? __pfx___driver_attach+0x10/0x10
[  137.182693]  bus_for_each_dev+0x100/0x190
[  137.182693]  ? __pfx_bus_for_each_dev+0x10/0x10
[  137.182693]  ? __kasan_check_read+0x15/0x20
[  137.182693]  ? srso_return_thunk+0x5/0x5f
[  137.182693]  ? _raw_spin_unlock+0x27/0x50
[  137.182693]  driver_attach+0x41/0x60
[  137.182693]  bus_add_driver+0x2a8/0x580
[  137.182693]  driver_register+0x141/0x480
[  137.182693]  __pci_register_driver+0x1d6/0x2a0
[  137.182693]  ? srso_return_thunk+0x5/0x5f
[  137.182693]  ? esrt_sysfs_init+0x1cd/0x5d0
[  137.182693]  ? __pfx_sp_mod_init+0x10/0x10
[  137.182693]  sp_pci_init+0x22/0x30
[  137.182693]  sp_mod_init+0x14/0x30
[  137.182693]  ? __pfx_sp_mod_init+0x10/0x10
[  137.182693]  do_one_initcall+0xd1/0x470
[  137.182693]  ? __pfx_do_one_initcall+0x10/0x10
[  137.182693]  ? parameq+0x80/0xf0
[  137.182693]  ? srso_return_thunk+0x5/0x5f
[  137.182693]  ? __kmalloc+0x3b0/0x4e0
[  137.182693]  ? kernel_init_freeable+0x92d/0x1050
[  137.182693]  ? kasan_populate_vmalloc_pte+0x171/0x190
[  137.182693]  ? srso_return_thunk+0x5/0x5f
[  137.182693]  kernel_init_freeable+0xa64/0x1050
[  137.182693]  ? __pfx_kernel_init+0x10/0x10
[  137.182693]  kernel_init+0x24/0x160
[  137.182693]  ? __switch_to_asm+0x3e/0x70
[  137.182693]  ret_from_fork+0x40/0x80
[  137.182693]  ? __pfx_kernel_init+0x10/0x10
[  137.182693]  ret_from_fork_asm+0x1b/0x30
[  137.182693]  </TASK>
[  137.182693] Modules linked in:
[  137.538483] ---[ end trace 0000000000000000 ]---

Fixes: 1b05ece ("crypto: ccp - During shutdown, check SEV data pointer before using")
Cc: stable@vger.kernel.org
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Acked-by: John Allen <john.allen@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Unfortunately the commit `fd8958efe877` introduced another error
causing the `descs` array to overflow. This reults in further crashes
easily reproducible by `sendmsg` system call.

[ 1080.836473] general protection fault, probably for non-canonical address 0x400300015528b00a: 0000 [#1] PREEMPT SMP PTI
[ 1080.869326] RIP: 0010:hfi1_ipoib_build_ib_tx_headers.constprop.0+0xe1/0x2b0 [hfi1]
--
[ 1080.974535] Call Trace:
[ 1080.976990]  <TASK>
[ 1081.021929]  hfi1_ipoib_send_dma_common+0x7a/0x2e0 [hfi1]
[ 1081.027364]  hfi1_ipoib_send_dma_list+0x62/0x270 [hfi1]
[ 1081.032633]  hfi1_ipoib_send+0x112/0x300 [hfi1]
[ 1081.042001]  ipoib_start_xmit+0x2a9/0x2d0 [ib_ipoib]
[ 1081.046978]  dev_hard_start_xmit+0xc4/0x210
--
[ 1081.148347]  __sys_sendmsg+0x59/0xa0

crash> ipoib_txreq 0xffff9cfeba229f00
struct ipoib_txreq {
  txreq = {
    list = {
      next = 0xffff9cfeba229f00,
      prev = 0xffff9cfeba229f00
    },
    descp = 0xffff9cfeba229f40,
    coalesce_buf = 0x0,
    wait = 0xffff9cfea4e69a48,
    complete = 0xffffffffc0fe0760 <hfi1_ipoib_sdma_complete>,
    packet_len = 0x46d,
    tlen = 0x0,
    num_desc = 0x0,
    desc_limit = 0x6,
    next_descq_idx = 0x45c,
    coalesce_idx = 0x0,
    flags = 0x0,
    descs = {{
        qw = {0x8024000120dffb00, 0x4}  # SDMA_DESC0_FIRST_DESC_FLAG (bit 63)
      }, {
        qw = {  0x3800014231b108, 0x4}
      }, {
        qw = { 0x310000e4ee0fcf0, 0x8}
      }, {
        qw = {  0x3000012e9f8000, 0x8}
      }, {
        qw = {  0x59000dfb9d0000, 0x8}
      }, {
        qw = {  0x78000e02e40000, 0x8}
      }}
  },
  sdma_hdr =  0x400300015528b000,  <<< invalid pointer in the tx request structure
  sdma_status = 0x0,                   SDMA_DESC0_LAST_DESC_FLAG (bit 62)
  complete = 0x0,
  priv = 0x0,
  txq = 0xffff9cfea4e69880,
  skb = 0xffff9d099809f400
}

If an SDMA send consists of exactly 6 descriptors and requires dword
padding (in the 7th descriptor), the sdma_txreq descriptor array is not
properly expanded and the packet will overflow into the container
structure. This results in a panic when the send completion runs. The
exact panic varies depending on what elements of the container structure
get corrupted. The fix is to use the correct expression in
_pad_sdma_tx_descs() to test the need to expand the descriptor array.

With this patch the crashes are no longer reproducible and the machine is
stable.

Fixes: fd8958e ("IB/hfi1: Fix sdma.h tx->num_descs off-by-one errors")
Cc: stable@vger.kernel.org
Reported-by: Mats Kronberg <kronberg@nsc.liu.se>
Tested-by: Mats Kronberg <kronberg@nsc.liu.se>
Signed-off-by: Daniel Vacek <neelx@redhat.com>
Link: https://lore.kernel.org/r/20240201081009.1109442-1-neelx@redhat.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

When a PCI device is dynamically added, the kernel oopses with a NULL
pointer dereference:

  BUG: Kernel NULL pointer dereference on read at 0x00000030
  Faulting instruction address: 0xc0000000006bbe5c
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in: rpadlpar_io rpaphp rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs xsk_diag bonding nft_compat nf_tables nfnetlink rfkill binfmt_misc dm_multipath rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_umad ib_iser libiscsi scsi_transport_iscsi ib_ipoib rdma_cm iw_cm ib_cm mlx5_ib ib_uverbs ib_core pseries_rng drm drm_panel_orientation_quirks xfs libcrc32c mlx5_core mlxfw sd_mod t10_pi sg tls ibmvscsi ibmveth scsi_transport_srp vmx_crypto pseries_wdt psample dm_mirror dm_region_hash dm_log dm_mod fuse
  CPU: 17 PID: 2685 Comm: drmgr Not tainted 6.7.0-203405+ torvalds#66
  Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries
  NIP:  c0000000006bbe5c LR: c000000000a13e68 CTR: c0000000000579f8
  REGS: c00000009924f240 TRAP: 0300   Not tainted  (6.7.0-203405+)
  MSR:  8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 24002220  XER: 20040006
  CFAR: c000000000a13e64 DAR: 0000000000000030 DSISR: 40000000 IRQMASK: 0
  ...
  NIP sysfs_add_link_to_group+0x34/0x94
  LR  iommu_device_link+0x5c/0x118
  Call Trace:
   iommu_init_device+0x26c/0x318 (unreliable)
   iommu_device_link+0x5c/0x118
   iommu_init_device+0xa8/0x318
   iommu_probe_device+0xc0/0x134
   iommu_bus_notifier+0x44/0x104
   notifier_call_chain+0xb8/0x19c
   blocking_notifier_call_chain+0x64/0x98
   bus_notify+0x50/0x7c
   device_add+0x640/0x918
   pci_device_add+0x23c/0x298
   of_create_pci_dev+0x400/0x884
   of_scan_pci_dev+0x124/0x1b0
   __of_scan_bus+0x78/0x18c
   pcibios_scan_phb+0x2a4/0x3b0
   init_phb_dynamic+0xb8/0x110
   dlpar_add_slot+0x170/0x3b8 [rpadlpar_io]
   add_slot_store.part.0+0xb4/0x130 [rpadlpar_io]
   kobj_attr_store+0x2c/0x48
   sysfs_kf_write+0x64/0x78
   kernfs_fop_write_iter+0x1b0/0x290
   vfs_write+0x350/0x4a0
   ksys_write+0x84/0x140
   system_call_exception+0x124/0x330
   system_call_vectored_common+0x15c/0x2ec

Commit a940904 ("powerpc/iommu: Add iommu_ops to report capabilities
and allow blocking domains") broke DLPAR add of PCI devices.

The above added iommu_device structure to pci_controller. During
system boot, PCI devices are discovered and this newly added iommu_device
structure is initialized by a call to iommu_device_register().

During DLPAR add of a PCI device, a new pci_controller structure is
allocated but there are no calls made to iommu_device_register()
interface.

Fix is to register the iommu device during DLPAR add as well.

Fixes: a940904 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains")
Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com>
[mpe: Trim oops and tweak some change log wording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240122222407.39603-1-gbatra@linux.ibm.com

When task_tag >= 32 (in MCQ mode) and sizeof(unsigned int) == 4, 1U <<
task_tag will out of bounds for a u32 mask. Fix this up to prevent
SHIFT_ISSUE (bitwise shifts that are out of bounds for their data type).

[name:debug_monitors&]Unexpected kernel BRK exception at EL1
[name:traps&]Internal error: BRK handler: 00000000f2005514 [#1] PREEMPT SMP
[name:mediatek_cpufreq_hw&]cpufreq stop DVFS log done
[name:mrdump&]Kernel Offset: 0x1ba5800000 from 0xffffffc008000000
[name:mrdump&]PHYS_OFFSET: 0x80000000
[name:mrdump&]pstate: 22400005 (nzCv daif +PAN -UAO)
[name:mrdump&]pc : [0xffffffdbaf52bb2c] ufshcd_clear_cmd+0x280/0x288
[name:mrdump&]lr : [0xffffffdbaf52a774] ufshcd_wait_for_dev_cmd+0x3e4/0x82c
[name:mrdump&]sp : ffffffc0081471b0
<snip>
Workqueue: ufs_eh_wq_0 ufshcd_err_handler
Call trace:
 dump_backtrace+0xf8/0x144
 show_stack+0x18/0x24
 dump_stack_lvl+0x78/0x9c
 dump_stack+0x18/0x44
 mrdump_common_die+0x254/0x480 [mrdump]
 ipanic_die+0x20/0x30 [mrdump]
 notify_die+0x15c/0x204
 die+0x10c/0x5f8
 arm64_notify_die+0x74/0x13c
 do_debug_exception+0x164/0x26c
 el1_dbg+0x64/0x80
 el1h_64_sync_handler+0x3c/0x90
 el1h_64_sync+0x68/0x6c
 ufshcd_clear_cmd+0x280/0x288
 ufshcd_wait_for_dev_cmd+0x3e4/0x82c
 ufshcd_exec_dev_cmd+0x5bc/0x9ac
 ufshcd_verify_dev_init+0x84/0x1c8
 ufshcd_probe_hba+0x724/0x1ce0
 ufshcd_host_reset_and_restore+0x260/0x574
 ufshcd_reset_and_restore+0x138/0xbd0
 ufshcd_err_handler+0x1218/0x2f28
 process_one_work+0x5fc/0x1140
 worker_thread+0x7d8/0xe20
 kthread+0x25c/0x468
 ret_from_fork+0x10/0x20

Signed-off-by: Alice Chao <alice.chao@mediatek.com>
Link: https://lore.kernel.org/r/20240205104905.24929-1-alice.chao@mediatek.com
Reviewed-by: Stanley Jhu <chu.stanley@gmail.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

With default config, the value of NR_CPUS is 64. When HW platform has
more then 64 cpus, system will crash on these platforms. MAX_CORE_PIC
is the maximum cpu number in MADT table (max physical number) which can
exceed the supported maximum cpu number (NR_CPUS, max logical number),
but kernel should not crash. Kernel should boot cpus with NR_CPUS, let
the remainder cpus stay in BIOS.

The potential crash reason is that the array acpi_core_pic[NR_CPUS] can
be overflowed when parsing MADT table, and it is obvious that CORE_PIC
should be corresponding to physical core rather than logical core, so it
is better to define the array as acpi_core_pic[MAX_CORE_PIC].

With the patch, system can boot up 64 vcpus with qemu parameter -smp 128,
otherwise system will crash with the following message.

[    0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000420000004259, era == 90000000037a5f0c, ra == 90000000037a46ec
[    0.000000] Oops[#1]:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.8.0-rc2+ torvalds#192
[    0.000000] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
[    0.000000] pc 90000000037a5f0c ra 90000000037a46ec tp 9000000003c90000 sp 9000000003c93d60
[    0.000000] a0 0000000000000019 a1 9000000003d93bc0 a2 0000000000000000 a3 9000000003c93bd8
[    0.000000] a4 9000000003c93a74 a5 9000000083c93a67 a6 9000000003c938f0 a7 0000000000000005
[    0.000000] t0 0000420000004201 t1 0000000000000000 t2 0000000000000001 t3 0000000000000001
[    0.000000] t4 0000000000000003 t5 0000000000000000 t6 0000000000000030 t7 0000000000000063
[    0.000000] t8 0000000000000014 u0 ffffffffffffffff s9 0000000000000000 s0 9000000003caee98
[    0.000000] s1 90000000041b0480 s2 9000000003c93da0 s3 9000000003c93d98 s4 9000000003c93d90
[    0.000000] s5 9000000003caa000 s6 000000000a7fd000 s7 000000000f556b60 s8 000000000e0a4330
[    0.000000]    ra: 90000000037a46ec platform_init+0x214/0x250
[    0.000000]   ERA: 90000000037a5f0c efi_runtime_init+0x30/0x94
[    0.000000]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
[    0.000000]  PRMD: 00000000 (PPLV0 -PIE -PWE)
[    0.000000]  EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
[    0.000000]  ECFG: 00070800 (LIE=11 VS=7)
[    0.000000] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
[    0.000000]  BADV: 0000420000004259
[    0.000000]  PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
[    0.000000] Modules linked in:
[    0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____))
[    0.000000] Stack : 9000000003c93a14 9000000003800898 90000000041844f8 90000000037a46ec
[    0.000000]         000000000a7fd000 0000000008290000 0000000000000000 0000000000000000
[    0.000000]         0000000000000000 0000000000000000 00000000019d8000 000000000f556b60
[    0.000000]         000000000a7fd000 000000000f556b08 9000000003ca7700 9000000003800000
[    0.000000]         9000000003c93e50 9000000003800898 9000000003800108 90000000037a484c
[    0.000000]         000000000e0a4330 000000000f556b60 000000000a7fd000 000000000f556b08
[    0.000000]         9000000003ca7700 9000000004184000 0000000000200000 000000000e02b018
[    0.000000]         000000000a7fd000 90000000037a0790 9000000003800108 0000000000000000
[    0.000000]         0000000000000000 000000000e0a4330 000000000f556b60 000000000a7fd000
[    0.000000]         000000000f556b08 000000000eaae298 000000000eaa5040 0000000000200000
[    0.000000]         ...
[    0.000000] Call Trace:
[    0.000000] [<90000000037a5f0c>] efi_runtime_init+0x30/0x94
[    0.000000] [<90000000037a46ec>] platform_init+0x214/0x250
[    0.000000] [<90000000037a484c>] setup_arch+0x124/0x45c
[    0.000000] [<90000000037a0790>] start_kernel+0x90/0x670
[    0.000000] [<900000000378b0d8>] kernel_entry+0xd8/0xdc

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

syzbot reported the following general protection fault [1]:

general protection fault, probably for non-canonical address 0xdffffc0000000010: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000080-0x0000000000000087]
...
RIP: 0010:tipc_udp_is_known_peer+0x9c/0x250 net/tipc/udp_media.c:291
...
Call Trace:
 <TASK>
 tipc_udp_nl_bearer_add+0x212/0x2f0 net/tipc/udp_media.c:646
 tipc_nl_bearer_add+0x21e/0x360 net/tipc/bearer.c:1089
 genl_family_rcv_msg_doit+0x1fc/0x2e0 net/netlink/genetlink.c:972
 genl_family_rcv_msg net/netlink/genetlink.c:1052 [inline]
 genl_rcv_msg+0x561/0x800 net/netlink/genetlink.c:1067
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2544
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x53b/0x810 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0x8b7/0xd70 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0xd5/0x180 net/socket.c:745
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The cause of this issue is that when tipc_nl_bearer_add() is called with
the TIPC_NLA_BEARER_UDP_OPTS attribute, tipc_udp_nl_bearer_add() is called
even if the bearer is not UDP.

tipc_udp_is_known_peer() called by tipc_udp_nl_bearer_add() assumes that
the media_ptr field of the tipc_bearer has an udp_bearer type object, so
the function goes crazy for non-UDP bearers.

This patch fixes the issue by checking the bearer type before calling
tipc_udp_nl_bearer_add() in tipc_nl_bearer_add().

Fixes: ef20cd4 ("tipc: introduce UDP replicast")
Reported-and-tested-by: syzbot+5142b87a9abc510e14fa@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5142b87a9abc510e14fa [1]
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Link: https://lore.kernel.org/r/20240131152310.4089541-1-syoshida@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

The change try to fix below error specific to RV platform:

BUG: kernel NULL pointer dereference, address: 0000000000000008
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 4 PID: 917 Comm: sway Not tainted 6.3.9-arch1-1 #1 124dc55df4f5272ccb409f39ef4872fc2b3376a2
Hardware name: LENOVO 20NKS01Y00/20NKS01Y00, BIOS R12ET61W(1.31 ) 07/28/2022
RIP: 0010:drm_dp_atomic_find_time_slots+0x5e/0x260 [drm_display_helper]
Code: 01 00 00 48 8b 85 60 05 00 00 48 63 80 88 00 00 00 3b 43 28 0f 8d 2e 01 00 00 48 8b 53 30 48 8d 04 80 48 8d 04 c2 48 8b 40 18 <48> 8>
RSP: 0018:ffff960cc2df77d8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff8afb87e81280 RCX: 0000000000000224
RDX: ffff8afb9ee37c00 RSI: ffff8afb8da1a578 RDI: ffff8afb87e81280
RBP: ffff8afb83d67000 R08: 0000000000000001 R09: ffff8afb9652f850
R10: ffff960cc2df7908 R11: 0000000000000002 R12: 0000000000000000
R13: ffff8afb8d7688a0 R14: ffff8afb8da1a578 R15: 0000000000000224
FS:  00007f4dac35ce00(0000) GS:ffff8afe30b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000010ddc6000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 ? __die+0x23/0x70
 ? page_fault_oops+0x171/0x4e0
 ? plist_add+0xbe/0x100
 ? exc_page_fault+0x7c/0x180
 ? asm_exc_page_fault+0x26/0x30
 ? drm_dp_atomic_find_time_slots+0x5e/0x260 [drm_display_helper 0e67723696438d8e02b741593dd50d80b44c2026]
 ? drm_dp_atomic_find_time_slots+0x28/0x260 [drm_display_helper 0e67723696438d8e02b741593dd50d80b44c2026]
 compute_mst_dsc_configs_for_link+0x2ff/0xa40 [amdgpu 62e600d2a75e9158e1cd0a243bdc8e6da040c054]
 ? fill_plane_buffer_attributes+0x419/0x510 [amdgpu 62e600d2a75e9158e1cd0a243bdc8e6da040c054]
 compute_mst_dsc_configs_for_state+0x1e1/0x250 [amdgpu 62e600d2a75e9158e1cd0a243bdc8e6da040c054]
 amdgpu_dm_atomic_check+0xecd/0x1190 [amdgpu 62e600d2a75e9158e1cd0a243bdc8e6da040c054]
 drm_atomic_check_only+0x5c5/0xa40
 drm_mode_atomic_ioctl+0x76e/0xbc0
 ? _copy_to_user+0x25/0x30
 ? drm_ioctl+0x296/0x4b0
 ? __pfx_drm_mode_atomic_ioctl+0x10/0x10
 drm_ioctl_kernel+0xcd/0x170
 drm_ioctl+0x26d/0x4b0
 ? __pfx_drm_mode_atomic_ioctl+0x10/0x10
 amdgpu_drm_ioctl+0x4e/0x90 [amdgpu 62e600d2a75e9158e1cd0a243bdc8e6da040c054]
 __x64_sys_ioctl+0x94/0xd0
 do_syscall_64+0x60/0x90
 ? do_syscall_64+0x6c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f4dad17f76f
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c>
RSP: 002b:00007ffd9ae859f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000055e255a55900 RCX: 00007f4dad17f76f
RDX: 00007ffd9ae85a90 RSI: 00000000c03864bc RDI: 000000000000000b
RBP: 00007ffd9ae85a90 R08: 0000000000000003 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000c03864bc
R13: 000000000000000b R14: 000055e255a7fc60 R15: 000055e255a01eb0
 </TASK>
Modules linked in: rfcomm snd_seq_dummy snd_hrtimer snd_seq snd_seq_device ccm cmac algif_hash algif_skcipher af_alg joydev mousedev bnep >
 typec libphy k10temp ipmi_msghandler roles i2c_scmi acpi_cpufreq mac_hid nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_mas>
CR2: 0000000000000008
---[ end trace 0000000000000000 ]---
RIP: 0010:drm_dp_atomic_find_time_slots+0x5e/0x260 [drm_display_helper]
Code: 01 00 00 48 8b 85 60 05 00 00 48 63 80 88 00 00 00 3b 43 28 0f 8d 2e 01 00 00 48 8b 53 30 48 8d 04 80 48 8d 04 c2 48 8b 40 18 <48> 8>
RSP: 0018:ffff960cc2df77d8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff8afb87e81280 RCX: 0000000000000224
RDX: ffff8afb9ee37c00 RSI: ffff8afb8da1a578 RDI: ffff8afb87e81280
RBP: ffff8afb83d67000 R08: 0000000000000001 R09: ffff8afb9652f850
R10: ffff960cc2df7908 R11: 0000000000000002 R12: 0000000000000000
R13: ffff8afb8d7688a0 R14: ffff8afb8da1a578 R15: 0000000000000224
FS:  00007f4dac35ce00(0000) GS:ffff8afe30b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000010ddc6000 CR4: 00000000003506e0

With a second DP monitor connected, drm_atomic_state in dm atomic check
sequence does not include the connector state for the old/existing/first
DP monitor. In such case, dsc determination policy would hit a null ptr
when it tries to iterate the old/existing stream that does not have a
valid connector state attached to it. When that happens, dm atomic check
should call drm_atomic_get_connector_state for a new connector state.
Existing dm has already done that, except for RV due to it does not have
official support of dsc where .num_dsc is not defined in dcn10 resource
cap, that prevent from getting drm_atomic_get_connector_state called.
So, skip dsc determination policy for ASICs that don't have DSC support.

Cc: stable@vger.kernel.org # 6.1+
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2314
Reviewed-by: Wayne Lin <wayne.lin@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

…line_page

When I did soft offline stress test, a machine was observed to crash with
the following message:

  kernel BUG at include/linux/memcontrol.h:554!
  invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 5 PID: 3837 Comm: hwpoison.sh Not tainted 6.7.0-next-20240112-00001-g8ecf3e7fb7c8-dirty torvalds#97
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  RIP: 0010:folio_memcg+0xaf/0xd0
  Code: 10 5b 5d c3 cc cc cc cc 48 c7 c6 08 b1 f2 b2 48 89 ef e8 b4 c5 f8 ff 90 0f 0b 48 c7 c6 d0 b0 f2 b2 48 89 ef e8 a2 c5 f8 ff 90 <0f> 0b 48 c7 c6 08 b1 f2 b2 48 89 ef e8 90 c5 f8 ff 90 0f 0b 66 66
  RSP: 0018:ffffb6c043657c98 EFLAGS: 00000296
  RAX: 000000000000004b RBX: ffff932bc1d1e401 RCX: ffff933abfb5c908
  RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff933abfb5c900
  RBP: ffffea6f04019080 R08: ffffffffb3338ce8 R09: 0000000000009ffb
  R10: 00000000000004dd R11: ffffffffb3308d00 R12: ffffea6f04019080
  R13: ffffea6f04019080 R14: 0000000000000001 R15: ffffb6c043657da0
  FS:  00007f6c60f6b740(0000) GS:ffff933abfb40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000559c3bc8b980 CR3: 0000000107f1c000 CR4: 00000000000006f0
  Call Trace:
   <TASK>
   split_huge_page_to_list+0x4d/0x1380
   try_to_split_thp_page+0x3a/0xf0
   soft_offline_page+0x1ea/0x8a0
   soft_offline_page_store+0x52/0x90
   kernfs_fop_write_iter+0x118/0x1b0
   vfs_write+0x30b/0x430
   ksys_write+0x5e/0xe0
   do_syscall_64+0xb0/0x1b0
   entry_SYSCALL_64_after_hwframe+0x6d/0x75
  RIP: 0033:0x7f6c60d14697
  Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
  RSP: 002b:00007ffe9b72b8d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007f6c60d14697
  RDX: 000000000000000c RSI: 0000559c3bc8b980 RDI: 0000000000000001
  RBP: 0000559c3bc8b980 R08: 00007f6c60dd1460 R09: 000000007fffffff
  R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
  R13: 00007f6c60e1a780 R14: 00007f6c60e16600 R15: 00007f6c60e15a00

The problem is that page->mapping is overloaded with slab->slab_list or
slabs fields now, so slab pages could be taken as non-LRU movable pages if
field slabs contains PAGE_MAPPING_MOVABLE or slab_list->prev is set to
LIST_POISON2.  These slab pages will be treated as thp later leading to
crash in split_huge_page_to_list().

Link: https://lkml.kernel.org/r/20240126065837.2100184-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20240124084014.1772906-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Fixes: 130d4df ("mm/sl[au]b: rearrange struct slab fields to allow larger rcu_head")
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When configuring a hugetlb filesystem via the fsconfig() syscall, there is
a possible NULL dereference in hugetlbfs_fill_super() caused by assigning
NULL to ctx->hstate in hugetlbfs_parse_param() when the requested pagesize
is non valid.

E.g: Taking the following steps:

     fd = fsopen("hugetlbfs", FSOPEN_CLOEXEC);
     fsconfig(fd, FSCONFIG_SET_STRING, "pagesize", "1024", 0);
     fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);

Given that the requested "pagesize" is invalid, ctxt->hstate will be replaced
with NULL, losing its previous value, and we will print an error:

 ...
 ...
 case Opt_pagesize:
 ps = memparse(param->string, &rest);
 ctx->hstate = h;
 if (!ctx->hstate) {
         pr_err("Unsupported page size %lu MB\n", ps / SZ_1M);
         return -EINVAL;
 }
 return 0;
 ...
 ...

This is a problem because later on, we will dereference ctxt->hstate in
hugetlbfs_fill_super()

 ...
 ...
 sb->s_blocksize = huge_page_size(ctx->hstate);
 ...
 ...

Causing below Oops.

Fix this by replacing cxt->hstate value only when then pagesize is known
to be valid.

 kernel: hugetlbfs: Unsupported page size 0 MB
 kernel: BUG: kernel NULL pointer dereference, address: 0000000000000028
 kernel: #PF: supervisor read access in kernel mode
 kernel: #PF: error_code(0x0000) - not-present page
 kernel: PGD 800000010f66c067 P4D 800000010f66c067 PUD 1b22f8067 PMD 0
 kernel: Oops: 0000 [#1] PREEMPT SMP PTI
 kernel: CPU: 4 PID: 5659 Comm: syscall Tainted: G            E      6.8.0-rc2-default+ torvalds#22 5a47c3fef76212addcc6eb71344aabc35190ae8f
 kernel: Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.0016.D04.1705030402 05/03/2017
 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0
 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28
 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246
 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004
 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000
 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004
 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000
 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400
 kernel: FS:  00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000
 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0
 kernel: Call Trace:
 kernel:  <TASK>
 kernel:  ? __die_body+0x1a/0x60
 kernel:  ? page_fault_oops+0x16f/0x4a0
 kernel:  ? search_bpf_extables+0x65/0x70
 kernel:  ? fixup_exception+0x22/0x310
 kernel:  ? exc_page_fault+0x69/0x150
 kernel:  ? asm_exc_page_fault+0x22/0x30
 kernel:  ? __pfx_hugetlbfs_fill_super+0x10/0x10
 kernel:  ? hugetlbfs_fill_super+0xb4/0x1a0
 kernel:  ? hugetlbfs_fill_super+0x28/0x1a0
 kernel:  ? __pfx_hugetlbfs_fill_super+0x10/0x10
 kernel:  vfs_get_super+0x40/0xa0
 kernel:  ? __pfx_bpf_lsm_capable+0x10/0x10
 kernel:  vfs_get_tree+0x25/0xd0
 kernel:  vfs_cmd_create+0x64/0xe0
 kernel:  __x64_sys_fsconfig+0x395/0x410
 kernel:  do_syscall_64+0x80/0x160
 kernel:  ? syscall_exit_to_user_mode+0x82/0x240
 kernel:  ? do_syscall_64+0x8d/0x160
 kernel:  ? syscall_exit_to_user_mode+0x82/0x240
 kernel:  ? do_syscall_64+0x8d/0x160
 kernel:  ? exc_page_fault+0x69/0x150
 kernel:  entry_SYSCALL_64_after_hwframe+0x6e/0x76
 kernel: RIP: 0033:0x7ffbc0cb87c9
 kernel: Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 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 8b 0d 97 96 0d 00 f7 d8 64 89 01 48
 kernel: RSP: 002b:00007ffc29d2f388 EFLAGS: 00000206 ORIG_RAX: 00000000000001af
 kernel: RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffbc0cb87c9
 kernel: RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
 kernel: RBP: 00007ffc29d2f3b0 R08: 0000000000000000 R09: 0000000000000000
 kernel: R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
 kernel: R13: 00007ffc29d2f4c0 R14: 0000000000000000 R15: 0000000000000000
 kernel:  </TASK>
 kernel: Modules linked in: rpcsec_gss_krb5(E) auth_rpcgss(E) nfsv4(E) dns_resolver(E) nfs(E) lockd(E) grace(E) sunrpc(E) netfs(E) af_packet(E) bridge(E) stp(E) llc(E) iscsi_ibft(E) iscsi_boot_sysfs(E) intel_rapl_msr(E) intel_rapl_common(E) iTCO_wdt(E) intel_pmc_bxt(E) sb_edac(E) iTCO_vendor_support(E) x86_pkg_temp_thermal(E) intel_powerclamp(E) coretemp(E) kvm_intel(E) rfkill(E) ipmi_ssif(E) kvm(E) acpi_ipmi(E) irqbypass(E) pcspkr(E) igb(E) ipmi_si(E) mei_me(E) i2c_i801(E) joydev(E) intel_pch_thermal(E) i2c_smbus(E) dca(E) lpc_ich(E) mei(E) ipmi_devintf(E) ipmi_msghandler(E) acpi_pad(E) tiny_power_button(E) button(E) fuse(E) efi_pstore(E) configfs(E) ip_tables(E) x_tables(E) ext4(E) mbcache(E) jbd2(E) hid_generic(E) usbhid(E) sd_mod(E) t10_pi(E) crct10dif_pclmul(E) crc32_pclmul(E) crc32c_intel(E) polyval_clmulni(E) ahci(E) xhci_pci(E) polyval_generic(E) gf128mul(E) ghash_clmulni_intel(E) sha512_ssse3(E) sha256_ssse3(E) xhci_pci_renesas(E) libahci(E) ehci_pci(E) sha1_ssse3(E) xhci_hcd(E) ehci_hcd(E) libata(E)
 kernel:  mgag200(E) i2c_algo_bit(E) usbcore(E) wmi(E) sg(E) dm_multipath(E) dm_mod(E) scsi_dh_rdac(E) scsi_dh_emc(E) scsi_dh_alua(E) scsi_mod(E) scsi_common(E) aesni_intel(E) crypto_simd(E) cryptd(E)
 kernel: Unloaded tainted modules: acpi_cpufreq(E):1 fjes(E):1
 kernel: CR2: 0000000000000028
 kernel: ---[ end trace 0000000000000000 ]---
 kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0
 kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28
 kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246
 kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004
 kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000
 kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004
 kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000
 kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400
 kernel: FS:  00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000
 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0

Link: https://lkml.kernel.org/r/20240130210418.3771-1-osalvador@suse.de
Fixes: 3202198 ("hugetlbfs: Convert to fs_context")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The below commit  introduced a WARN when phy state is not in the states:
PHY_HALTED, PHY_READY and PHY_UP.
commit 744d23c ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")

When cpsw_new resumes, there have port in PHY_NOLINK state, so the below
warning comes out. Set mac_managed_pm be true to tell mdio that the phy
resume/suspend is managed by the mac, to fix the following warning:

WARNING: CPU: 0 PID: 965 at drivers/net/phy/phy_device.c:326 mdio_bus_phy_resume+0x140/0x144
CPU: 0 PID: 965 Comm: sh Tainted: G           O       6.1.46-g247b2535b2 #1
Hardware name: Generic AM33XX (Flattened Device Tree)
 unwind_backtrace from show_stack+0x18/0x1c
 show_stack from dump_stack_lvl+0x24/0x2c
 dump_stack_lvl from __warn+0x84/0x15c
 __warn from warn_slowpath_fmt+0x1a8/0x1c8
 warn_slowpath_fmt from mdio_bus_phy_resume+0x140/0x144
 mdio_bus_phy_resume from dpm_run_callback+0x3c/0x140
 dpm_run_callback from device_resume+0xb8/0x2b8
 device_resume from dpm_resume+0x144/0x314
 dpm_resume from dpm_resume_end+0x14/0x20
 dpm_resume_end from suspend_devices_and_enter+0xd0/0x924
 suspend_devices_and_enter from pm_suspend+0x2e0/0x33c
 pm_suspend from state_store+0x74/0xd0
 state_store from kernfs_fop_write_iter+0x104/0x1ec
 kernfs_fop_write_iter from vfs_write+0x1b8/0x358
 vfs_write from ksys_write+0x78/0xf8
 ksys_write from ret_fast_syscall+0x0/0x54
Exception stack(0xe094dfa8 to 0xe094dff0)
dfa0:                   00000004 005c3fb8 00000001 005c3fb8 00000004 00000001
dfc0: 00000004 005c3fb8 b6f6bba0 00000004 00000004 0059edb8 00000000 00000000
dfe0: 00000004 bed918f0 b6f09bd3 b6e89a66

Cc: <stable@vger.kernel.org> # v6.0+
Fixes: 744d23c ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")
Fixes: fba863b ("net: phy: make PHY PM ops a no-op if MAC driver manages PHY PM")
Signed-off-by: Sinthu Raja <sinthu.raja@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

The below commit  introduced a WARN when phy state is not in the states:
PHY_HALTED, PHY_READY and PHY_UP.
commit 744d23c ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")

When cpsw resumes, there have port in PHY_NOLINK state, so the below
warning comes out. Set mac_managed_pm be true to tell mdio that the phy
resume/suspend is managed by the mac, to fix the following warning:

WARNING: CPU: 0 PID: 965 at drivers/net/phy/phy_device.c:326 mdio_bus_phy_resume+0x140/0x144
CPU: 0 PID: 965 Comm: sh Tainted: G           O       6.1.46-g247b2535b2 #1
Hardware name: Generic AM33XX (Flattened Device Tree)
 unwind_backtrace from show_stack+0x18/0x1c
 show_stack from dump_stack_lvl+0x24/0x2c
 dump_stack_lvl from __warn+0x84/0x15c
 __warn from warn_slowpath_fmt+0x1a8/0x1c8
 warn_slowpath_fmt from mdio_bus_phy_resume+0x140/0x144
 mdio_bus_phy_resume from dpm_run_callback+0x3c/0x140
 dpm_run_callback from device_resume+0xb8/0x2b8
 device_resume from dpm_resume+0x144/0x314
 dpm_resume from dpm_resume_end+0x14/0x20
 dpm_resume_end from suspend_devices_and_enter+0xd0/0x924
 suspend_devices_and_enter from pm_suspend+0x2e0/0x33c
 pm_suspend from state_store+0x74/0xd0
 state_store from kernfs_fop_write_iter+0x104/0x1ec
 kernfs_fop_write_iter from vfs_write+0x1b8/0x358
 vfs_write from ksys_write+0x78/0xf8
 ksys_write from ret_fast_syscall+0x0/0x54
Exception stack(0xe094dfa8 to 0xe094dff0)
dfa0:                   00000004 005c3fb8 00000001 005c3fb8 00000004 00000001
dfc0: 00000004 005c3fb8 b6f6bba0 00000004 00000004 0059edb8 00000000 00000000
dfe0: 00000004 bed918f0 b6f09bd3 b6e89a66

Cc: <stable@vger.kernel.org> # v6.0+
Fixes: 744d23c ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")
Fixes: fba863b ("net: phy: make PHY PM ops a no-op if MAC driver manages PHY PM")
Signed-off-by: Sinthu Raja <sinthu.raja@ti.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Recently, I've been hitting following deadlock warning during dpll pin
dump:

[52804.637962] ======================================================
[52804.638536] WARNING: possible circular locking dependency detected
[52804.639111] 6.8.0-rc2jiri+ #1 Not tainted
[52804.639529] ------------------------------------------------------
[52804.640104] python3/2984 is trying to acquire lock:
[52804.640581] ffff88810e642678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: netlink_dump+0xb3/0x780
[52804.641417]
               but task is already holding lock:
[52804.642010] ffffffff83bde4c8 (dpll_lock){+.+.}-{3:3}, at: dpll_lock_dumpit+0x13/0x20
[52804.642747]
               which lock already depends on the new lock.

[52804.643551]
               the existing dependency chain (in reverse order) is:
[52804.644259]
               -> #1 (dpll_lock){+.+.}-{3:3}:
[52804.644836]        lock_acquire+0x174/0x3e0
[52804.645271]        __mutex_lock+0x119/0x1150
[52804.645723]        dpll_lock_dumpit+0x13/0x20
[52804.646169]        genl_start+0x266/0x320
[52804.646578]        __netlink_dump_start+0x321/0x450
[52804.647056]        genl_family_rcv_msg_dumpit+0x155/0x1e0
[52804.647575]        genl_rcv_msg+0x1ed/0x3b0
[52804.648001]        netlink_rcv_skb+0xdc/0x210
[52804.648440]        genl_rcv+0x24/0x40
[52804.648831]        netlink_unicast+0x2f1/0x490
[52804.649290]        netlink_sendmsg+0x36d/0x660
[52804.649742]        __sock_sendmsg+0x73/0xc0
[52804.650165]        __sys_sendto+0x184/0x210
[52804.650597]        __x64_sys_sendto+0x72/0x80
[52804.651045]        do_syscall_64+0x6f/0x140
[52804.651474]        entry_SYSCALL_64_after_hwframe+0x46/0x4e
[52804.652001]
               -> #0 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}:
[52804.652650]        check_prev_add+0x1ae/0x1280
[52804.653107]        __lock_acquire+0x1ed3/0x29a0
[52804.653559]        lock_acquire+0x174/0x3e0
[52804.653984]        __mutex_lock+0x119/0x1150
[52804.654423]        netlink_dump+0xb3/0x780
[52804.654845]        __netlink_dump_start+0x389/0x450
[52804.655321]        genl_family_rcv_msg_dumpit+0x155/0x1e0
[52804.655842]        genl_rcv_msg+0x1ed/0x3b0
[52804.656272]        netlink_rcv_skb+0xdc/0x210
[52804.656721]        genl_rcv+0x24/0x40
[52804.657119]        netlink_unicast+0x2f1/0x490
[52804.657570]        netlink_sendmsg+0x36d/0x660
[52804.658022]        __sock_sendmsg+0x73/0xc0
[52804.658450]        __sys_sendto+0x184/0x210
[52804.658877]        __x64_sys_sendto+0x72/0x80
[52804.659322]        do_syscall_64+0x6f/0x140
[52804.659752]        entry_SYSCALL_64_after_hwframe+0x46/0x4e
[52804.660281]
               other info that might help us debug this:

[52804.661077]  Possible unsafe locking scenario:

[52804.661671]        CPU0                    CPU1
[52804.662129]        ----                    ----
[52804.662577]   lock(dpll_lock);
[52804.662924]                                lock(nlk_cb_mutex-GENERIC);
[52804.663538]                                lock(dpll_lock);
[52804.664073]   lock(nlk_cb_mutex-GENERIC);
[52804.664490]

The issue as follows: __netlink_dump_start() calls control->start(cb)
with nlk->cb_mutex held. In control->start(cb) the dpll_lock is taken.
Then nlk->cb_mutex is released and taken again in netlink_dump(), while
dpll_lock still being held. That leads to ABBA deadlock when another
CPU races with the same operation.

Fix this by moving dpll_lock taking into dumpit() callback which ensures
correct lock taking order.

Fixes: 9d71b54 ("dpll: netlink: Add DPLL framework base functions")
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Link: https://lore.kernel.org/r/20240207115902.371649-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

While running the CI for an unrelated change I hit the following panic
with generic/648 on btrfs_holes_spacecache.

assertion failed: block_start != EXTENT_MAP_HOLE, in fs/btrfs/extent_io.c:1385
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:1385!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 2695096 Comm: fsstress Kdump: loaded Tainted: G        W          6.8.0-rc2+ #1
RIP: 0010:__extent_writepage_io.constprop.0+0x4c1/0x5c0
Call Trace:
 <TASK>
 extent_write_cache_pages+0x2ac/0x8f0
 extent_writepages+0x87/0x110
 do_writepages+0xd5/0x1f0
 filemap_fdatawrite_wbc+0x63/0x90
 __filemap_fdatawrite_range+0x5c/0x80
 btrfs_fdatawrite_range+0x1f/0x50
 btrfs_write_out_cache+0x507/0x560
 btrfs_write_dirty_block_groups+0x32a/0x420
 commit_cowonly_roots+0x21b/0x290
 btrfs_commit_transaction+0x813/0x1360
 btrfs_sync_file+0x51a/0x640
 __x64_sys_fdatasync+0x52/0x90
 do_syscall_64+0x9c/0x190
 entry_SYSCALL_64_after_hwframe+0x6e/0x76

This happens because we fail to write out the free space cache in one
instance, come back around and attempt to write it again.  However on
the second pass through we go to call btrfs_get_extent() on the inode to
get the extent mapping.  Because this is a new block group, and with the
free space inode we always search the commit root to avoid deadlocking
with the tree, we find nothing and return a EXTENT_MAP_HOLE for the
requested range.

This happens because the first time we try to write the space cache out
we hit an error, and on an error we drop the extent mapping.  This is
normal for normal files, but the free space cache inode is special.  We
always expect the extent map to be correct.  Thus the second time
through we end up with a bogus extent map.

Since we're deprecating this feature, the most straightforward way to
fix this is to simply skip dropping the extent map range for this failed
range.

I shortened the test by using error injection to stress the area to make
it easier to reproduce.  With this patch in place we no longer panic
with my error injection test.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Avoid the following warning by making sure to free the allocated
resources in case that qedr_init_user_queue() fail.

-----------[ cut here ]-----------
WARNING: CPU: 0 PID: 143192 at drivers/infiniband/core/rdma_core.c:874 uverbs_destroy_ufile_hw+0xcf/0xf0 [ib_uverbs]
Modules linked in: tls target_core_user uio target_core_pscsi target_core_file target_core_iblock ib_srpt ib_srp scsi_transport_srp nfsd nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs 8021q garp mrp stp llc ext4 mbcache jbd2 opa_vnic ib_umad ib_ipoib sunrpc rdma_ucm ib_isert iscsi_target_mod target_core_mod ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm hfi1 intel_rapl_msr intel_rapl_common mgag200 qedr sb_edac drm_shmem_helper rdmavt x86_pkg_temp_thermal drm_kms_helper intel_powerclamp ib_uverbs coretemp i2c_algo_bit kvm_intel dell_wmi_descriptor ipmi_ssif sparse_keymap kvm ib_core rfkill syscopyarea sysfillrect video sysimgblt irqbypass ipmi_si ipmi_devintf fb_sys_fops rapl iTCO_wdt mxm_wmi iTCO_vendor_support intel_cstate pcspkr dcdbas intel_uncore ipmi_msghandler lpc_ich acpi_power_meter mei_me mei fuse drm xfs libcrc32c qede sd_mod ahci libahci t10_pi sg crct10dif_pclmul crc32_pclmul crc32c_intel qed libata tg3
ghash_clmulni_intel megaraid_sas crc8 wmi [last unloaded: ib_srpt]
CPU: 0 PID: 143192 Comm: fi_rdm_tagged_p Kdump: loaded Not tainted 5.14.0-408.el9.x86_64 #1
Hardware name: Dell Inc. PowerEdge R430/03XKDV, BIOS 2.14.0 01/25/2022
RIP: 0010:uverbs_destroy_ufile_hw+0xcf/0xf0 [ib_uverbs]
Code: 5d 41 5c 41 5d 41 5e e9 0f 26 1b dd 48 89 df e8 67 6a ff ff 49 8b 86 10 01 00 00 48 85 c0 74 9c 4c 89 e7 e8 83 c0 cb dd eb 92 <0f> 0b eb be 0f 0b be 04 00 00 00 48 89 df e8 8e f5 ff ff e9 6d ff
RSP: 0018:ffffb7c6cadfbc60 EFLAGS: 00010286
RAX: ffff8f0889ee3f60 RBX: ffff8f088c1a5200 RCX: 00000000802a0016
RDX: 00000000802a0017 RSI: 0000000000000001 RDI: ffff8f0880042600
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8f11fffd5000 R11: 0000000000039000 R12: ffff8f0d5b36cd80
R13: ffff8f088c1a5250 R14: ffff8f1206d91000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8f11d7c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000147069200e20 CR3: 00000001c7210002 CR4: 00000000001706f0
Call Trace:
<TASK>
? show_trace_log_lvl+0x1c4/0x2df
? show_trace_log_lvl+0x1c4/0x2df
? ib_uverbs_close+0x1f/0xb0 [ib_uverbs]
? uverbs_destroy_ufile_hw+0xcf/0xf0 [ib_uverbs]
? __warn+0x81/0x110
? uverbs_destroy_ufile_hw+0xcf/0xf0 [ib_uverbs]
? report_bug+0x10a/0x140
? handle_bug+0x3c/0x70
? exc_invalid_op+0x14/0x70
? asm_exc_invalid_op+0x16/0x20
? uverbs_destroy_ufile_hw+0xcf/0xf0 [ib_uverbs]
ib_uverbs_close+0x1f/0xb0 [ib_uverbs]
__fput+0x94/0x250
task_work_run+0x5c/0x90
do_exit+0x270/0x4a0
do_group_exit+0x2d/0x90
get_signal+0x87c/0x8c0
arch_do_signal_or_restart+0x25/0x100
? ib_uverbs_ioctl+0xc2/0x110 [ib_uverbs]
exit_to_user_mode_loop+0x9c/0x130
exit_to_user_mode_prepare+0xb6/0x100
syscall_exit_to_user_mode+0x12/0x40
do_syscall_64+0x69/0x90
? syscall_exit_work+0x103/0x130
? syscall_exit_to_user_mode+0x22/0x40
? do_syscall_64+0x69/0x90
? syscall_exit_work+0x103/0x130
? syscall_exit_to_user_mode+0x22/0x40
? do_syscall_64+0x69/0x90
? do_syscall_64+0x69/0x90
? common_interrupt+0x43/0xa0
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x1470abe3ec6b
Code: Unable to access opcode bytes at RIP 0x1470abe3ec41.
RSP: 002b:00007fff13ce9108 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 00007fff13ce9218 RCX: 00001470abe3ec6b
RDX: 00007fff13ce9200 RSI: 00000000c0181b01 RDI: 0000000000000004
RBP: 00007fff13ce91e0 R08: 0000558d9655da10 R09: 0000558d9655dd00
R10: 00007fff13ce95c0 R11: 0000000000000246 R12: 00007fff13ce9358
R13: 0000000000000013 R14: 0000558d9655db50 R15: 00007fff13ce9470
</TASK>
--[ end trace 888a9b92e04c5c97 ]--

Fixes: df15856 ("RDMA/qedr: restructure functions that create/destroy QPs")
Signed-off-by: Kamal Heib <kheib@redhat.com>
Link: https://lore.kernel.org/r/20240208223628.2040841-1-kheib@redhat.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

shutdown_pirq and startup_pirq are not taking the
irq_mapping_update_lock because they can't due to lock inversion. Both
are called with the irq_desc->lock being taking. The lock order,
however, is first irq_mapping_update_lock and then irq_desc->lock.

This opens multiple races:
- shutdown_pirq can be interrupted by a function that allocates an event
  channel:

  CPU0                        CPU1
  shutdown_pirq {
    xen_evtchn_close(e)
                              __startup_pirq {
                                EVTCHNOP_bind_pirq
                                  -> returns just freed evtchn e
                                set_evtchn_to_irq(e, irq)
                              }
    xen_irq_info_cleanup() {
      set_evtchn_to_irq(e, -1)
    }
  }

  Assume here event channel e refers here to the same event channel
  number.
  After this race the evtchn_to_irq mapping for e is invalid (-1).

- __startup_pirq races with __unbind_from_irq in a similar way. Because
  __startup_pirq doesn't take irq_mapping_update_lock it can grab the
  evtchn that __unbind_from_irq is currently freeing and cleaning up. In
  this case even though the event channel is allocated, its mapping can
  be unset in evtchn_to_irq.

The fix is to first cleanup the mappings and then close the event
channel. In this way, when an event channel gets allocated it's
potential previous evtchn_to_irq mappings are guaranteed to be unset already.
This is also the reverse order of the allocation where first the event
channel is allocated and then the mappings are setup.

On a 5.10 kernel prior to commit 3fcdaf3 ("xen/events: modify internal
[un]bind interfaces"), we hit a BUG like the following during probing of NVMe
devices. The issue is that during nvme_setup_io_queues, pci_free_irq
is called for every device which results in a call to shutdown_pirq.
With many nvme devices it's therefore likely to hit this race during
boot because there will be multiple calls to shutdown_pirq and
startup_pirq are running potentially in parallel.

  ------------[ cut here ]------------
  blkfront: xvda: barrier or flush: disabled; persistent grants: enabled; indirect descriptors: enabled; bounce buffer: enabled
  kernel BUG at drivers/xen/events/events_base.c:499!
  invalid opcode: 0000 [#1] SMP PTI
  CPU: 44 PID: 375 Comm: kworker/u257:23 Not tainted 5.10.201-191.748.amzn2.x86_64 #1
  Hardware name: Xen HVM domU, BIOS 4.11.amazon 08/24/2006
  Workqueue: nvme-reset-wq nvme_reset_work
  RIP: 0010:bind_evtchn_to_cpu+0xdf/0xf0
  Code: 5d 41 5e c3 cc cc cc cc 44 89 f7 e8 2b 55 ad ff 49 89 c5 48 85 c0 0f 84 64 ff ff ff 4c 8b 68 30 41 83 fe ff 0f 85 60 ff ff ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 0f 1f 44 00 00
  RSP: 0000:ffffc9000d533b08 EFLAGS: 00010046
  RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000006
  RDX: 0000000000000028 RSI: 00000000ffffffff RDI: 00000000ffffffff
  RBP: ffff888107419680 R08: 0000000000000000 R09: ffffffff82d72b00
  R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000001ed
  R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000002
  FS:  0000000000000000(0000) GS:ffff88bc8b500000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 0000000002610001 CR4: 00000000001706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? show_trace_log_lvl+0x1c1/0x2d9
   ? show_trace_log_lvl+0x1c1/0x2d9
   ? set_affinity_irq+0xdc/0x1c0
   ? __die_body.cold+0x8/0xd
   ? die+0x2b/0x50
   ? do_trap+0x90/0x110
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? do_error_trap+0x65/0x80
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? exc_invalid_op+0x4e/0x70
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? asm_exc_invalid_op+0x12/0x20
   ? bind_evtchn_to_cpu+0xdf/0xf0
   ? bind_evtchn_to_cpu+0xc5/0xf0
   set_affinity_irq+0xdc/0x1c0
   irq_do_set_affinity+0x1d7/0x1f0
   irq_setup_affinity+0xd6/0x1a0
   irq_startup+0x8a/0xf0
   __setup_irq+0x639/0x6d0
   ? nvme_suspend+0x150/0x150
   request_threaded_irq+0x10c/0x180
   ? nvme_suspend+0x150/0x150
   pci_request_irq+0xa8/0xf0
   ? __blk_mq_free_request+0x74/0xa0
   queue_request_irq+0x6f/0x80
   nvme_create_queue+0x1af/0x200
   nvme_create_io_queues+0xbd/0xf0
   nvme_setup_io_queues+0x246/0x320
   ? nvme_irq_check+0x30/0x30
   nvme_reset_work+0x1c8/0x400
   process_one_work+0x1b0/0x350
   worker_thread+0x49/0x310
   ? process_one_work+0x350/0x350
   kthread+0x11b/0x140
   ? __kthread_bind_mask+0x60/0x60
   ret_from_fork+0x22/0x30
  Modules linked in:
  ---[ end trace a11715de1eee1873 ]---

Fixes: d46a78b ("xen: implement pirq type event channels")
Cc: stable@vger.kernel.org
Co-debugged-by: Andrew Panyakin <apanyaki@amazon.com>
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20240124163130.31324-1-mheyne@amazon.de
Signed-off-by: Juergen Gross <jgross@suse.com>

Turning on CONFIG_DMA_API_DEBUG_SG results in the following warning:

DMA-API: mmci-pl18x 48220000.mmc: cacheline tracking EEXIST,
overlapping mappings aren't supported
WARNING: CPU: 1 PID: 51 at kernel/dma/debug.c:568
add_dma_entry+0x234/0x2f4
Modules linked in:
CPU: 1 PID: 51 Comm: kworker/1:2 Not tainted 6.1.28 #1
Hardware name: STMicroelectronics STM32MP257F-EV1 Evaluation Board (DT)
Workqueue: events_freezable mmc_rescan
Call trace:
add_dma_entry+0x234/0x2f4
debug_dma_map_sg+0x198/0x350
__dma_map_sg_attrs+0xa0/0x110
dma_map_sg_attrs+0x10/0x2c
sdmmc_idma_prep_data+0x80/0xc0
mmci_prep_data+0x38/0x84
mmci_start_data+0x108/0x2dc
mmci_request+0xe4/0x190
__mmc_start_request+0x68/0x140
mmc_start_request+0x94/0xc0
mmc_wait_for_req+0x70/0x100
mmc_send_tuning+0x108/0x1ac
sdmmc_execute_tuning+0x14c/0x210
mmc_execute_tuning+0x48/0xec
mmc_sd_init_uhs_card.part.0+0x208/0x464
mmc_sd_init_card+0x318/0x89c
mmc_attach_sd+0xe4/0x180
mmc_rescan+0x244/0x320

DMA API debug brings to light leaking dma-mappings as dma_map_sg and
dma_unmap_sg are not correctly balanced.

If an error occurs in mmci_cmd_irq function, only mmci_dma_error
function is called and as this API is not managed on stm32 variant,
dma_unmap_sg is never called in this error path.

Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Fixes: 46b723d ("mmc: mmci: add stm32 sdmmc variant")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240207143951.938144-1-christophe.kerello@foss.st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

…39_FILTER)

Lock jsk->sk to prevent UAF when setsockopt(..., SO_J1939_FILTER, ...)
modifies jsk->filters while receiving packets.

Following trace was seen on affected system:
 ==================================================================
 BUG: KASAN: slab-use-after-free in j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
 Read of size 4 at addr ffff888012144014 by task j1939/350

 CPU: 0 PID: 350 Comm: j1939 Tainted: G        W  OE      6.5.0-rc5 #1
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
 Call Trace:
  print_report+0xd3/0x620
  ? kasan_complete_mode_report_info+0x7d/0x200
  ? j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
  kasan_report+0xc2/0x100
  ? j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
  __asan_load4+0x84/0xb0
  j1939_sk_recv_match_one+0x1af/0x2d0 [can_j1939]
  j1939_sk_recv+0x20b/0x320 [can_j1939]
  ? __kasan_check_write+0x18/0x20
  ? __pfx_j1939_sk_recv+0x10/0x10 [can_j1939]
  ? j1939_simple_recv+0x69/0x280 [can_j1939]
  ? j1939_ac_recv+0x5e/0x310 [can_j1939]
  j1939_can_recv+0x43f/0x580 [can_j1939]
  ? __pfx_j1939_can_recv+0x10/0x10 [can_j1939]
  ? raw_rcv+0x42/0x3c0 [can_raw]
  ? __pfx_j1939_can_recv+0x10/0x10 [can_j1939]
  can_rcv_filter+0x11f/0x350 [can]
  can_receive+0x12f/0x190 [can]
  ? __pfx_can_rcv+0x10/0x10 [can]
  can_rcv+0xdd/0x130 [can]
  ? __pfx_can_rcv+0x10/0x10 [can]
  __netif_receive_skb_one_core+0x13d/0x150
  ? __pfx___netif_receive_skb_one_core+0x10/0x10
  ? __kasan_check_write+0x18/0x20
  ? _raw_spin_lock_irq+0x8c/0xe0
  __netif_receive_skb+0x23/0xb0
  process_backlog+0x107/0x260
  __napi_poll+0x69/0x310
  net_rx_action+0x2a1/0x580
  ? __pfx_net_rx_action+0x10/0x10
  ? __pfx__raw_spin_lock+0x10/0x10
  ? handle_irq_event+0x7d/0xa0
  __do_softirq+0xf3/0x3f8
  do_softirq+0x53/0x80
  </IRQ>
  <TASK>
  __local_bh_enable_ip+0x6e/0x70
  netif_rx+0x16b/0x180
  can_send+0x32b/0x520 [can]
  ? __pfx_can_send+0x10/0x10 [can]
  ? __check_object_size+0x299/0x410
  raw_sendmsg+0x572/0x6d0 [can_raw]
  ? __pfx_raw_sendmsg+0x10/0x10 [can_raw]
  ? apparmor_socket_sendmsg+0x2f/0x40
  ? __pfx_raw_sendmsg+0x10/0x10 [can_raw]
  sock_sendmsg+0xef/0x100
  sock_write_iter+0x162/0x220
  ? __pfx_sock_write_iter+0x10/0x10
  ? __rtnl_unlock+0x47/0x80
  ? security_file_permission+0x54/0x320
  vfs_write+0x6ba/0x750
  ? __pfx_vfs_write+0x10/0x10
  ? __fget_light+0x1ca/0x1f0
  ? __rcu_read_unlock+0x5b/0x280
  ksys_write+0x143/0x170
  ? __pfx_ksys_write+0x10/0x10
  ? __kasan_check_read+0x15/0x20
  ? fpregs_assert_state_consistent+0x62/0x70
  __x64_sys_write+0x47/0x60
  do_syscall_64+0x60/0x90
  ? do_syscall_64+0x6d/0x90
  ? irqentry_exit+0x3f/0x50
  ? exc_page_fault+0x79/0xf0
  entry_SYSCALL_64_after_hwframe+0x6e/0xd8

 Allocated by task 348:
  kasan_save_stack+0x2a/0x50
  kasan_set_track+0x29/0x40
  kasan_save_alloc_info+0x1f/0x30
  __kasan_kmalloc+0xb5/0xc0
  __kmalloc_node_track_caller+0x67/0x160
  j1939_sk_setsockopt+0x284/0x450 [can_j1939]
  __sys_setsockopt+0x15c/0x2f0
  __x64_sys_setsockopt+0x6b/0x80
  do_syscall_64+0x60/0x90
  entry_SYSCALL_64_after_hwframe+0x6e/0xd8

 Freed by task 349:
  kasan_save_stack+0x2a/0x50
  kasan_set_track+0x29/0x40
  kasan_save_free_info+0x2f/0x50
  __kasan_slab_free+0x12e/0x1c0
  __kmem_cache_free+0x1b9/0x380
  kfree+0x7a/0x120
  j1939_sk_setsockopt+0x3b2/0x450 [can_j1939]
  __sys_setsockopt+0x15c/0x2f0
  __x64_sys_setsockopt+0x6b/0x80
  do_syscall_64+0x60/0x90
  entry_SYSCALL_64_after_hwframe+0x6e/0xd8

Fixes: 9d71dd0 ("can: add support of SAE J1939 protocol")
Reported-by: Sili Luo <rootlab@huawei.com>
Suggested-by: Sili Luo <rootlab@huawei.com>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/all/20231020133814.383996-1-o.rempel@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

…in attach

The function spapr_tce_platform_iommu_attach_dev() is missing to call
iommu_group_put() when the domain is already set. This refcount leak
shows up with BUG_ON() during DLPAR remove operation as:

  KernelBug: Kernel bug in state 'None': kernel BUG at arch/powerpc/platforms/pseries/iommu.c:100!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=8192 NUMA pSeries
  <snip>
  Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_016) hv:phyp pSeries
  NIP:  c0000000000ff4d4 LR: c0000000000ff4cc CTR: 0000000000000000
  REGS: c0000013aed5f840 TRAP: 0700   Tainted: G          I         (6.8.0-rc3-autotest-g99bd3cb0d12e)
  MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 44002402  XER: 20040000
  CFAR: c000000000a0d170 IRQMASK: 0
  ...
  NIP iommu_reconfig_notifier+0x94/0x200
  LR  iommu_reconfig_notifier+0x8c/0x200
  Call Trace:
    iommu_reconfig_notifier+0x8c/0x200 (unreliable)
    notifier_call_chain+0xb8/0x19c
    blocking_notifier_call_chain+0x64/0x98
    of_reconfig_notify+0x44/0xdc
    of_detach_node+0x78/0xb0
    ofdt_write.part.0+0x86c/0xbb8
    proc_reg_write+0xf4/0x150
    vfs_write+0xf8/0x488
    ksys_write+0x84/0x140
    system_call_exception+0x138/0x330
    system_call_vectored_common+0x15c/0x2ec

The patch adds the missing iommu_group_put() call.

Fixes: a8ca9fc ("powerpc/iommu: Do not do platform domain attach atctions after probe")
Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Closes: https://lore.kernel.org/all/274e0d2b-b5cc-475e-94e6-8427e88e271d@linux.vnet.ibm.com/
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/170784021983.6249.10039296655906636112.stgit@linux.ibm.com

… into HEAD

KVM/riscv fixes for 6.8, take #1

- Fix steal-time related sparse warnings

The function xe_vm_prepare_vma was blindly accepting zero as the
number of fences and forwarded that to drm_exec_prepare_obj.

However, that leads to an out-of-bounds shift in the
dma_resv_reserve_fences() and while one could argue that the
dma_resv code should be robust against that, avoid attempting
to reserve zero fences.

Relevant stack trace:

[773.183188] ------------[ cut here ]------------
[773.183199] UBSAN: shift-out-of-bounds in ../include/linux/log2.h:57:13
[773.183241] shift exponent 64 is too large for 64-bit type 'long unsigned int'
[773.183254] CPU: 2 PID: 1816 Comm: xe_evict Tainted: G     U             6.8.0-rc3-xe #1
[773.183256] Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 2014 10/14/2022
[773.183257] Call Trace:
[773.183258]  <TASK>
[773.183260]  dump_stack_lvl+0xaf/0xd0
[773.183266]  dump_stack+0x10/0x20
[773.183283]  ubsan_epilogue+0x9/0x40
[773.183286]  __ubsan_handle_shift_out_of_bounds+0x10f/0x170
[773.183293]  dma_resv_reserve_fences.cold+0x2b/0x48
[773.183295]  ? ww_mutex_lock+0x3c/0x110
[773.183301]  drm_exec_prepare_obj+0x45/0x60 [drm_exec]
[773.183313]  xe_vm_prepare_vma+0x33/0x70 [xe]
[773.183375]  xe_vma_destroy_unlocked+0x55/0xa0 [xe]
[773.183427]  xe_vm_close_and_put+0x526/0x940 [xe]

Fixes: 2714d50 ("drm/xe: Convert pagefaulting code to use drm_exec")
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240208132115.3132-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit eb538b5)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

Correct blk-mq registration issue with module parameter
disable_managed_interrupts enabled.

When we turn off the default PCI_IRQ_AFFINITY flag, the driver needs to
register with blk-mq using blk_mq_map_queues(). The driver is currently
calling blk_mq_pci_map_queues() which results in a stack trace and possibly
undefined behavior.

Stack Trace:
[    7.860089] scsi host2: smartpqi
[    7.871934] WARNING: CPU: 0 PID: 238 at block/blk-mq-pci.c:52 blk_mq_pci_map_queues+0xca/0xd0
[    7.889231] Modules linked in: sd_mod t10_pi sg uas smartpqi(+) crc32c_intel scsi_transport_sas usb_storage dm_mirror dm_region_hash dm_log dm_mod ipmi_devintf ipmi_msghandler fuse
[    7.924755] CPU: 0 PID: 238 Comm: kworker/0:3 Not tainted 4.18.0-372.88.1.el8_6_smartpqi_test.x86_64 #1
[    7.944336] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 03/08/2022
[    7.963026] Workqueue: events work_for_cpu_fn
[    7.978275] RIP: 0010:blk_mq_pci_map_queues+0xca/0xd0
[    7.978278] Code: 48 89 de 89 c7 e8 f6 0f 4f 00 3b 05 c4 b7 8e 01 72 e1 5b 31 c0 5d 41 5c 41 5d 41 5e 41 5f e9 7d df 73 00 31 c0 e9 76 df 73 00 <0f> 0b eb bc 90 90 0f 1f 44 00 00 41 57 49 89 ff 41 56 41 55 41 54
[    7.978280] RSP: 0018:ffffa95fc3707d50 EFLAGS: 00010216
[    7.978283] RAX: 00000000ffffffff RBX: 0000000000000000 RCX: 0000000000000010
[    7.978284] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff9190c32d4310
[    7.978286] RBP: 0000000000000000 R08: ffffa95fc3707d38 R09: ffff91929b81ac00
[    7.978287] R10: 0000000000000001 R11: ffffa95fc3707ac0 R12: 0000000000000000
[    7.978288] R13: ffff9190c32d4000 R14: 00000000ffffffff R15: ffff9190c4c950a8
[    7.978290] FS:  0000000000000000(0000) GS:ffff9193efc00000(0000) knlGS:0000000000000000
[    7.978292] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    8.172814] CR2: 000055d11166c000 CR3: 00000002dae10002 CR4: 00000000007706f0
[    8.172816] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    8.172817] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    8.172818] PKRU: 55555554
[    8.172819] Call Trace:
[    8.172823]  blk_mq_alloc_tag_set+0x12e/0x310
[    8.264339]  scsi_add_host_with_dma.cold.9+0x30/0x245
[    8.279302]  pqi_ctrl_init+0xacf/0xc8e [smartpqi]
[    8.294085]  ? pqi_pci_probe+0x480/0x4c8 [smartpqi]
[    8.309015]  pqi_pci_probe+0x480/0x4c8 [smartpqi]
[    8.323286]  local_pci_probe+0x42/0x80
[    8.337855]  work_for_cpu_fn+0x16/0x20
[    8.351193]  process_one_work+0x1a7/0x360
[    8.364462]  ? create_worker+0x1a0/0x1a0
[    8.379252]  worker_thread+0x1ce/0x390
[    8.392623]  ? create_worker+0x1a0/0x1a0
[    8.406295]  kthread+0x10a/0x120
[    8.418428]  ? set_kthread_struct+0x50/0x50
[    8.431532]  ret_from_fork+0x1f/0x40
[    8.444137] ---[ end trace 1bf0173d39354506 ]---

Fixes: cf15c3e ("scsi: smartpqi: Add module param to disable managed ints")
Tested-by: Yogesh Chandra Pandey <YogeshChandra.Pandey@microchip.com>
Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mahesh Rajashekhara <mahesh.rajashekhara@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Reviewed-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Link: https://lore.kernel.org/r/20240213162200.1875970-2-don.brace@microchip.com
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

When trying to use copy_from_kernel_nofault() to read vsyscall page
through a bpf program, the following oops was reported:

  BUG: unable to handle page fault for address: ffffffffff600000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0
  Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
  RIP: 0010:copy_from_kernel_nofault+0x6f/0x110
  ......
  Call Trace:
   <TASK>
   ? copy_from_kernel_nofault+0x6f/0x110
   bpf_probe_read_kernel+0x1d/0x50
   bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d
   trace_call_bpf+0xc5/0x1c0
   perf_call_bpf_enter.isra.0+0x69/0xb0
   perf_syscall_enter+0x13e/0x200
   syscall_trace_enter+0x188/0x1c0
   do_syscall_64+0xb5/0xe0
   entry_SYSCALL_64_after_hwframe+0x6e/0x76
   </TASK>
  ......
  ---[ end trace 0000000000000000 ]---

The oops is triggered when:

1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall
page and invokes copy_from_kernel_nofault() which in turn calls
__get_user_asm().

2) Because the vsyscall page address is not readable from kernel space,
a page fault exception is triggered accordingly.

3) handle_page_fault() considers the vsyscall page address as a user
space address instead of a kernel space address. This results in the
fix-up setup by bpf not being applied and a page_fault_oops() is invoked
due to SMAP.

Considering handle_page_fault() has already considered the vsyscall page
address as a userspace address, fix the problem by disallowing vsyscall
page read for copy_from_kernel_nofault().

Originally-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: syzbot+72aa0161922eba61b50e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/CAG48ez06TZft=ATH1qh2c5mpS5BT8UakwNkzi6nvK5_djC-4Nw@mail.gmail.com
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/bpf/CABOYnLynjBoFZOf3Z4BhaZkc5hx_kHfsjiW+UWLoB=w33LvScw@mail.gmail.com
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240202103935.3154011-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Hou Tao says:

====================
Fix the read of vsyscall page through bpf

From: Hou Tao <houtao1@huawei.com>

Hi,

As reported by syzboot [1] and [2], when trying to read vsyscall page
by using bpf_probe_read_kernel() or bpf_probe_read(), oops may happen.

Thomas Gleixner had proposed a test patch [3], but it seems that no
formal patch is posted after about one month [4], so I post it instead
and add an Originally-by tag in patch #2.

Patch #1 makes is_vsyscall_vaddr() being a common helper. Patch #2 fixes
the problem by disallowing vsyscall page read for
copy_from_kernel_nofault(). Patch #3 adds one test case to ensure the
read of vsyscall page through bpf is rejected. Please see individual
patches for more details.

Comments are always welcome.

[1]: https://lore.kernel.org/bpf/CAG48ez06TZft=ATH1qh2c5mpS5BT8UakwNkzi6nvK5_djC-4Nw@mail.gmail.com/
[2]: https://lore.kernel.org/bpf/CABOYnLynjBoFZOf3Z4BhaZkc5hx_kHfsjiW+UWLoB=w33LvScw@mail.gmail.com/
[3]: https://lore.kernel.org/bpf/87r0jwquhv.ffs@tglx/
[4]: https://lore.kernel.org/bpf/e24b125c-8ff4-9031-6c53-67ff2e01f316@huaweicloud.com/

Change Log:
v3:
 * rephrase commit message for patch #1 & #2 (Sohil)
 * reword comments in copy_from_kernel_nofault_allowed() (Sohil)
 * add Rvb tag for patch #1 and Acked-by tag for patch #3 (Sohil, Yonghong)

v2: https://lore.kernel.org/bpf/20240126115423.3943360-1-houtao@huaweicloud.com/
  * move is_vsyscall_vaddr to asm/vsyscall.h instead (Sohil)
  * elaborate on the reason for disallowing of vsyscall page read in
    copy_from_kernel_nofault_allowed() (Sohil)
  * update the commit message of patch #2 to more clearly explain how
    the oops occurs. (Sohil)
  * update the commit message of patch #3 to explain the expected return
    values of various bpf helpers (Yonghong)

v1: https://lore.kernel.org/bpf/20240119073019.1528573-1-houtao@huaweicloud.com/
====================

Link: https://lore.kernel.org/r/20240202103935.3154011-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Olliver reported that his system crashes when plugging in Thunderbolt 1
device:

 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: 0000 [#1] PREEMPT SMP NOPTI
 RIP: 0010:tb_port_do_update_credits+0x1b/0x130 [thunderbolt]
 Call Trace:
  <TASK>
  ? __die+0x23/0x70
  ? page_fault_oops+0x171/0x4e0
  ? exc_page_fault+0x7f/0x180
  ? asm_exc_page_fault+0x26/0x30
  ? tb_port_do_update_credits+0x1b/0x130
  ? tb_switch_update_link_attributes+0x83/0xd0
  tb_switch_add+0x7a2/0xfe0
  tb_scan_port+0x236/0x6f0
  tb_handle_hotplug+0x6db/0x900
  process_one_work+0x171/0x340
  worker_thread+0x27b/0x3a0
  ? __pfx_worker_thread+0x10/0x10
  kthread+0xe5/0x120
  ? __pfx_kthread+0x10/0x10
  ret_from_fork+0x31/0x50
  ? __pfx_kthread+0x10/0x10
  ret_from_fork_asm+0x1b/0x30
  </TASK>

This is due the fact that some Thunderbolt 1 devices only have one lane
adapter. Fix this by checking for the lane 1 before we read its credits.

Reported-by: Olliver Schinagl <oliver@schinagl.nl>
Closes: https://lore.kernel.org/linux-usb/c24c7882-6254-4e68-8f22-f3e8f65dc84f@schinagl.nl/
Fixes: 81af295 ("thunderbolt: Add support for asymmetric link")
Cc: stable@vger.kernel.org
Cc: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

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

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>

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>

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>

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>

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>

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>

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>

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>

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>

The check_pmd_still_valid() call during collapse is currently only
protected by the mmap_lock in write mode, which was sufficient when
pt_reclaim always ran under mmap_lock in read mode.  However, since
madvise_dontneed can now execute under a per-VMA lock, this assumption is
no longer valid.  As a result, a race condition can occur between collapse
and PT_RECLAIM, potentially leading to a kernel panic.

 [   38.151897] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] SMP KASI
 [   38.153519] KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
 [   38.154605] CPU: 0 UID: 0 PID: 721 Comm: repro Not tainted 6.16.0-next-20250801-next-2025080 #1 PREEMPT(voluntary)
 [   38.155929] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org4
 [   38.157418] RIP: 0010:kasan_byte_accessible+0x15/0x30
 [   38.158125] Code: 03 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 b8 00 00 00 00 00 fc0
 [   38.160461] RSP: 0018:ffff88800feef678 EFLAGS: 00010286
 [   38.161220] RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 1ffffffff0dde60c
 [   38.162232] RDX: 0000000000000000 RSI: ffffffff85da1e18 RDI: dffffc0000000003
 [   38.163176] RBP: ffff88800feef698 R08: 0000000000000001 R09: 0000000000000000
 [   38.164195] R10: 0000000000000000 R11: ffff888016a8ba58 R12: 0000000000000018
 [   38.165189] R13: 0000000000000018 R14: ffffffff85da1e18 R15: 0000000000000000
 [   38.166100] FS:  0000000000000000(0000) GS:ffff8880e3b40000(0000) knlGS:0000000000000000
 [   38.167137] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [   38.167891] CR2: 00007f97fadfe504 CR3: 0000000007088005 CR4: 0000000000770ef0
 [   38.168812] PKRU: 55555554
 [   38.169275] Call Trace:
 [   38.169647]  <TASK>
 [   38.169975]  ? __kasan_check_byte+0x19/0x50
 [   38.170581]  lock_acquire+0xea/0x310
 [   38.171083]  ? rcu_is_watching+0x19/0xc0
 [   38.171615]  ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20
 [   38.172343]  ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30
 [   38.173130]  _raw_spin_lock+0x38/0x50
 [   38.173707]  ? __pte_offset_map_lock+0x1a2/0x3c0
 [   38.174390]  __pte_offset_map_lock+0x1a2/0x3c0
 [   38.174987]  ? __pfx___pte_offset_map_lock+0x10/0x10
 [   38.175724]  ? __pfx_pud_val+0x10/0x10
 [   38.176308]  ? __sanitizer_cov_trace_const_cmp1+0x1e/0x30
 [   38.177183]  unmap_page_range+0xb60/0x43e0
 [   38.177824]  ? __pfx_unmap_page_range+0x10/0x10
 [   38.178485]  ? mas_next_slot+0x133a/0x1a50
 [   38.179079]  unmap_single_vma.constprop.0+0x15b/0x250
 [   38.179830]  unmap_vmas+0x1fa/0x460
 [   38.180373]  ? __pfx_unmap_vmas+0x10/0x10
 [   38.180994]  ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20
 [   38.181877]  exit_mmap+0x1a2/0xb40
 [   38.182396]  ? lock_release+0x14f/0x2c0
 [   38.182929]  ? __pfx_exit_mmap+0x10/0x10
 [   38.183474]  ? __pfx___mutex_unlock_slowpath+0x10/0x10
 [   38.184188]  ? mutex_unlock+0x16/0x20
 [   38.184704]  mmput+0x132/0x370
 [   38.185208]  do_exit+0x7e7/0x28c0
 [   38.185682]  ? __this_cpu_preempt_check+0x21/0x30
 [   38.186328]  ? do_group_exit+0x1d8/0x2c0
 [   38.186873]  ? __pfx_do_exit+0x10/0x10
 [   38.187401]  ? __this_cpu_preempt_check+0x21/0x30
 [   38.188036]  ? _raw_spin_unlock_irq+0x2c/0x60
 [   38.188634]  ? lockdep_hardirqs_on+0x89/0x110
 [   38.189313]  do_group_exit+0xe4/0x2c0
 [   38.189831]  __x64_sys_exit_group+0x4d/0x60
 [   38.190413]  x64_sys_call+0x2174/0x2180
 [   38.190935]  do_syscall_64+0x6d/0x2e0
 [   38.191449]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

This patch moves the vma_start_write() call to precede
check_pmd_still_valid(), ensuring that the check is also properly
protected by the per-VMA lock.

Link: https://lkml.kernel.org/r/20250805035447.7958-1-21cnbao@gmail.com
Fixes: a6fde7a ("mm: use per_vma lock for MADV_DONTNEED")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Tested-by: "Lai, Yi" <yi1.lai@linux.intel.com>
Reported-by: "Lai, Yi" <yi1.lai@linux.intel.com>
Closes: https://lore.kernel.org/all/aJAFrYfyzGpbm+0m@ly-workstation/
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Tangquan Zheng <zhengtangquan@oppo.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Dev Jain <dev.jain@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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 ebs 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
Fixes: 19d7f65 ("btrfs: convert the buffer_radix to an xarray")
CC: stable@vger.kernel.org # 6.16+
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>

The existing code move the VF NIC to new namespace when NETDEV_REGISTER is
received on netvsc NIC. During deletion of the namespace,
default_device_exit_batch() >> default_device_exit_net() is called. When
netvsc NIC is moved back and registered to the default namespace, it
automatically brings VF NIC back to the default namespace. This will cause
the default_device_exit_net() >> for_each_netdev_safe loop unable to detect
the list end, and hit NULL ptr:

[  231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0
[  231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010
[  231.450246] #PF: supervisor read access in kernel mode
[  231.450579] #PF: error_code(0x0000) - not-present page
[  231.450916] PGD 17b8a8067 P4D 0
[  231.451163] Oops: Oops: 0000 [#1] SMP NOPTI
[  231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY
[  231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024
[  231.452692] Workqueue: netns cleanup_net
[  231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0
[  231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00
[  231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246
[  231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb
[  231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564
[  231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000
[  231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340
[  231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340
[  231.457161] FS:  0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000
[  231.457707] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0
[  231.458434] Call Trace:
[  231.458600]  <TASK>
[  231.458777]  ops_undo_list+0x100/0x220
[  231.459015]  cleanup_net+0x1b8/0x300
[  231.459285]  process_one_work+0x184/0x340

To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid
changing the netdev list when default_device_exit_net() is using it.

Cc: stable@vger.kernel.org
Fixes: 4c26280 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Link: https://patch.msgid.link/1754511711-11188-1-git-send-email-haiyangz@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Since EROFS handles decompression in non-atomic contexts due to
uncontrollable decompression latencies and vmap() usage, it tries
to detect atomic contexts and only kicks off a kworker on demand
in order to reduce unnecessary scheduling overhead.

However, the current approach is insufficient and can lead to
sleeping function calls in invalid contexts, causing kernel
warnings and potential system instability. See the stacktrace [1]
and previous discussion [2].

The current implementation only checks rcu_read_lock_any_held(),
which behaves inconsistently across different kernel configurations:

- When CONFIG_DEBUG_LOCK_ALLOC is enabled: correctly detects
  RCU critical sections by checking rcu_lock_map
- When CONFIG_DEBUG_LOCK_ALLOC is disabled: compiles to
  "!preemptible()", which only checks preempt_count and misses
  RCU critical sections

This patch introduces z_erofs_in_atomic() to provide comprehensive
atomic context detection:

1. Check RCU preemption depth when CONFIG_PREEMPTION is enabled,
   as RCU critical sections may not affect preempt_count but still
   require atomic handling

2. Always use async processing when CONFIG_PREEMPT_COUNT is disabled,
   as preemption state cannot be reliably determined

3. Fall back to standard preemptible() check for remaining cases

The function replaces the previous complex condition check and ensures
that z_erofs always uses (kthread_)work in atomic contexts to minimize
scheduling overhead and prevent sleeping in invalid contexts.

[1] Problem stacktrace
[ 61.266692] BUG: sleeping function called from invalid context at kernel/locking/rtmutex_api.c:510
[ 61.266702] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 107, name: irq/54-ufshcd
[ 61.266704] preempt_count: 0, expected: 0
[ 61.266705] RCU nest depth: 2, expected: 0
[ 61.266710] CPU: 0 UID: 0 PID: 107 Comm: irq/54-ufshcd Tainted: G W O 6.12.17 #1
[ 61.266714] Tainted: [W]=WARN, [O]=OOT_MODULE
[ 61.266715] Hardware name: schumacher (DT)
[ 61.266717] Call trace:
[ 61.266718] dump_backtrace+0x9c/0x100
[ 61.266727] show_stack+0x20/0x38
[ 61.266728] dump_stack_lvl+0x78/0x90
[ 61.266734] dump_stack+0x18/0x28
[ 61.266736] __might_resched+0x11c/0x180
[ 61.266743] __might_sleep+0x64/0xc8
[ 61.266745] mutex_lock+0x2c/0xc0
[ 61.266748] z_erofs_decompress_queue+0xe8/0x978
[ 61.266753] z_erofs_decompress_kickoff+0xa8/0x190
[ 61.266756] z_erofs_endio+0x168/0x288
[ 61.266758] bio_endio+0x160/0x218
[ 61.266762] blk_update_request+0x244/0x458
[ 61.266766] scsi_end_request+0x38/0x278
[ 61.266770] scsi_io_completion+0x4c/0x600
[ 61.266772] scsi_finish_command+0xc8/0xe8
[ 61.266775] scsi_complete+0x88/0x148
[ 61.266777] blk_mq_complete_request+0x3c/0x58
[ 61.266780] scsi_done_internal+0xcc/0x158
[ 61.266782] scsi_done+0x1c/0x30
[ 61.266783] ufshcd_compl_one_cqe+0x12c/0x438
[ 61.266786] __ufshcd_transfer_req_compl+0x2c/0x78
[ 61.266788] ufshcd_poll+0xf4/0x210
[ 61.266789] ufshcd_transfer_req_compl+0x50/0x88
[ 61.266791] ufshcd_intr+0x21c/0x7c8
[ 61.266792] irq_forced_thread_fn+0x44/0xd8
[ 61.266796] irq_thread+0x1a4/0x358
[ 61.266799] kthread+0x12c/0x138
[ 61.266802] ret_from_fork+0x10/0x20

[2] https://lore.kernel.org/r/58b661d0-0ebb-4b45-a10d-c5927fb791cd@paulmck-laptop

Signed-off-by: Junli Liu <liujunli@lixiang.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250805011957.911186-1-liujunli@lixiang.com
[ Gao Xiang: Use the original trace in v1. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

syzbot reported the splat below. [0]

When nsim_queue_uninit() is called from nsim_init_netdevsim(),
register_netdevice() has not been called, thus dev->dstats has
not been allocated.

Let's not call dev_dstats_rx_dropped_add() in such a case.

[0]
BUG: unable to handle page fault for address: ffff88809782c020
 PF: supervisor write access in kernel mode
 PF: error_code(0x0002) - not-present page
PGD 1b401067 P4D 1b401067 PUD 0
Oops: Oops: 0002 [#1] SMP KASAN NOPTI
CPU: 3 UID: 0 PID: 8476 Comm: syz.1.251 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #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:local_add arch/x86/include/asm/local.h:33 [inline]
RIP: 0010:u64_stats_add include/linux/u64_stats_sync.h:89 [inline]
RIP: 0010:dev_dstats_rx_dropped_add include/linux/netdevice.h:3027 [inline]
RIP: 0010:nsim_queue_free+0xba/0x120 drivers/net/netdevsim/netdev.c:714
Code: 07 77 6c 4a 8d 3c ed 20 7e f1 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 46 4a 03 1c ed 20 7e f1 8d <4c> 01 63 20 be 00 02 00 00 48 8d 3d 00 00 00 00 e8 61 2f 58 fa 48
RSP: 0018:ffffc900044af150 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: ffff88809782c000 RCX: 00000000000079c3
RDX: 1ffffffff1be2fc7 RSI: ffffffff8c15f380 RDI: ffffffff8df17e38
RBP: ffff88805f59d000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000003 R14: ffff88806ceb3d00 R15: ffffed100dfd308e
FS:  0000000000000000(0000) GS:ffff88809782c000(0063) knlGS:00000000f505db40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: ffff88809782c020 CR3: 000000006fc6a000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 nsim_queue_uninit drivers/net/netdevsim/netdev.c:993 [inline]
 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline]
 nsim_create+0xd0a/0x1260 drivers/net/netdevsim/netdev.c:1101
 __nsim_dev_port_add+0x435/0x7d0 drivers/net/netdevsim/dev.c:1438
 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1494 [inline]
 nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline]
 nsim_dev_reload_up+0x5b8/0x860 drivers/net/netdevsim/dev.c:1003
 devlink_reload+0x322/0x7c0 net/devlink/dev.c:474
 devlink_nl_reload_doit+0xe31/0x1410 net/devlink/dev.c:584
 genl_family_rcv_msg_doit+0x206/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf708e579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f505d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000172
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 0000000080000080
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
CR2: ffff88809782c020

Fixes: 2a68a22 ("netdevsim: account dropped packet length in stats on queue free")
Reported-by: syzbot+8aa80c6232008f7b957d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/688bb9ca.a00a0220.26d0e1.0050.GAE@google.com/
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250812162130.4129322-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Shuang reported sch_ets test-case [1] crashing in ets_class_qlen_notify()
after recent changes from Lion [2]. The problem is: in ets_qdisc_change()
we purge unused DWRR queues; the value of 'q->nbands' is the new one, and
the cleanup should be done with the old one. The problem is here since my
first attempts to fix ets_qdisc_change(), but it surfaced again after the
recent qdisc len accounting fixes. Fix it purging idle DWRR queues before
assigning a new value of 'q->nbands', so that all purge operations find a
consistent configuration:

 - old 'q->nbands' because it's needed by ets_class_find()
 - old 'q->nstrict' because it's needed by ets_class_is_strict()

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0000 [#1] SMP NOPTI
 CPU: 62 UID: 0 PID: 39457 Comm: tc Kdump: loaded Not tainted 6.12.0-116.el10.x86_64 #1 PREEMPT(voluntary)
 Hardware name: Dell Inc. PowerEdge R640/06DKY5, BIOS 2.12.2 07/09/2021
 RIP: 0010:__list_del_entry_valid_or_report+0x4/0x80
 Code: ff 4c 39 c7 0f 84 39 19 8e ff b8 01 00 00 00 c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 17 48 8b 4f 08 48 85 d2 0f 84 56 19 8e ff 48 85 c9 0f 84 ab
 RSP: 0018:ffffba186009f400 EFLAGS: 00010202
 RAX: 00000000000000d6 RBX: 0000000000000000 RCX: 0000000000000004
 RDX: ffff9f0fa29b69c0 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: ffffffffc12c2400 R08: 0000000000000008 R09: 0000000000000004
 R10: ffffffffffffffff R11: 0000000000000004 R12: 0000000000000000
 R13: ffff9f0f8cfe0000 R14: 0000000000100005 R15: 0000000000000000
 FS:  00007f2154f37480(0000) GS:ffff9f269c1c0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000001530be001 CR4: 00000000007726f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  <TASK>
  ets_class_qlen_notify+0x65/0x90 [sch_ets]
  qdisc_tree_reduce_backlog+0x74/0x110
  ets_qdisc_change+0x630/0xa40 [sch_ets]
  __tc_modify_qdisc.constprop.0+0x216/0x7f0
  tc_modify_qdisc+0x7c/0x120
  rtnetlink_rcv_msg+0x145/0x3f0
  netlink_rcv_skb+0x53/0x100
  netlink_unicast+0x245/0x390
  netlink_sendmsg+0x21b/0x470
  ____sys_sendmsg+0x39d/0x3d0
  ___sys_sendmsg+0x9a/0xe0
  __sys_sendmsg+0x7a/0xd0
  do_syscall_64+0x7d/0x160
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7f2155114084
 Code: 89 02 b8 ff ff ff ff eb bb 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 80 3d 25 f0 0c 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 89 54 24 1c 48 89
 RSP: 002b:00007fff1fd7a988 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000560ec063e5e0 RCX: 00007f2155114084
 RDX: 0000000000000000 RSI: 00007fff1fd7a9f0 RDI: 0000000000000003
 RBP: 00007fff1fd7aa60 R08: 0000000000000010 R09: 000000000000003f
 R10: 0000560ee9b3a010 R11: 0000000000000202 R12: 00007fff1fd7aae0
 R13: 000000006891ccde R14: 0000560ec063e5e0 R15: 00007fff1fd7aad0
  </TASK>

 [1] https://lore.kernel.org/netdev/e08c7f4a6882f260011909a868311c6e9b54f3e4.1639153474.git.dcaratti@redhat.com/
 [2] https://lore.kernel.org/netdev/d912cbd7-193b-4269-9857-525bee8bbb6a@gmail.com/

Cc: stable@vger.kernel.org
Fixes: 103406b ("net/sched: Always pass notifications when child class becomes empty")
Fixes: c062f2a ("net/sched: sch_ets: don't remove idle classes from the round-robin list")
Fixes: dcc68b4 ("net: sch_ets: Add a new Qdisc")
Reported-by: Li Shuang <shuali@redhat.com>
Closes: https://issues.redhat.com/browse/RHEL-108026
Reviewed-by: Petr Machata <petrm@nvidia.com>
Co-developed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Link: https://patch.msgid.link/7928ff6d17db47a2ae7cc205c44777b1f1950545.1755016081.git.dcaratti@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

…dfl()

[ Upstream commit f39489f ]

When getting an LLC CPU mask in the default CPU selection policy,
scx_select_cpu_dfl(), a pointer to the sched_domain is dereferenced
using rcu_read_lock() without holding rcu_read_lock(). Such an unprotected
dereference often causes the following warning and can cause an invalid
memory access in the worst case.

Therefore, protect dereference of a sched_domain pointer using a pair
of rcu_read_lock() and unlock().

[   20.996135] =============================
[   20.996345] WARNING: suspicious RCU usage
[   20.996563] 6.11.0-virtme torvalds#17 Tainted: G        W
[   20.996576] -----------------------------
[   20.996576] kernel/sched/ext.c:3323 suspicious rcu_dereference_check() usage!
[   20.996576]
[   20.996576] other info that might help us debug this:
[   20.996576]
[   20.996576]
[   20.996576] rcu_scheduler_active = 2, debug_locks = 1
[   20.996576] 4 locks held by kworker/8:1/140:
[   20.996576]  #0: ffff8b18c00dd348 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x4a0/0x590
[   20.996576]  #1: ffffb3da01f67e58 ((work_completion)(&dev->power.work)){+.+.}-{0:0}, at: process_one_work+0x1ba/0x590
[   20.996576]  #2: ffffffffa316f9f0 (&rcu_state.gp_wq){..-.}-{2:2}, at: swake_up_one+0x15/0x60
[   20.996576]  #3: ffff8b1880398a60 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0x59/0x7d0
[   20.996576]
[   20.996576] stack backtrace:
[   20.996576] CPU: 8 UID: 0 PID: 140 Comm: kworker/8:1 Tainted: G        W          6.11.0-virtme torvalds#17
[   20.996576] Tainted: [W]=WARN
[   20.996576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
[   20.996576] Workqueue: pm pm_runtime_work
[   20.996576] Sched_ext: simple (disabling+all), task: runnable_at=-6ms
[   20.996576] Call Trace:
[   20.996576]  <IRQ>
[   20.996576]  dump_stack_lvl+0x6f/0xb0
[   20.996576]  lockdep_rcu_suspicious.cold+0x4e/0x96
[   20.996576]  scx_select_cpu_dfl+0x234/0x260
[   20.996576]  select_task_rq_scx+0xfb/0x190
[   20.996576]  select_task_rq+0x47/0x110
[   20.996576]  try_to_wake_up+0x110/0x7d0
[   20.996576]  swake_up_one+0x39/0x60
[   20.996576]  rcu_core+0xb08/0xe50
[   20.996576]  ? srso_alias_return_thunk+0x5/0xfbef5
[   20.996576]  ? mark_held_locks+0x40/0x70
[   20.996576]  handle_softirqs+0xd3/0x410
[   20.996576]  irq_exit_rcu+0x78/0xa0
[   20.996576]  sysvec_apic_timer_interrupt+0x73/0x80
[   20.996576]  </IRQ>
[   20.996576]  <TASK>
[   20.996576]  asm_sysvec_apic_timer_interrupt+0x1a/0x20
[   20.996576] RIP: 0010:_raw_spin_unlock_irqrestore+0x36/0x70
[   20.996576] Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 11 b4 36 ff 48 89 df e8 99 0d 37 ff f7 c5 00 02 00 00 75 17 9c 58 f6 c4 02 75 2b <65> ff 0d 5b 55 3c 5e 74 16 5b 5d e9 95 8e 28 00 e8 a5 ee 44 ff 9c
[   20.996576] RSP: 0018:ffffb3da01f67d20 EFLAGS: 00000246
[   20.996576] RAX: 0000000000000002 RBX: ffffffffa4640220 RCX: 0000000000000040
[   20.996576] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa1c7b27b
[   20.996576] RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000
[   20.996576] R10: 0000000000000001 R11: 000000000000021c R12: 0000000000000246
[   20.996576] R13: ffff8b1881363958 R14: 0000000000000000 R15: ffff8b1881363800
[   20.996576]  ? _raw_spin_unlock_irqrestore+0x4b/0x70
[   20.996576]  serial_port_runtime_resume+0xd4/0x1a0
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  __rpm_callback+0x44/0x170
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  rpm_callback+0x55/0x60
[   20.996576]  ? __pfx_serial_port_runtime_resume+0x10/0x10
[   20.996576]  rpm_resume+0x582/0x7b0
[   20.996576]  pm_runtime_work+0x7c/0xb0
[   20.996576]  process_one_work+0x1fb/0x590
[   20.996576]  worker_thread+0x18e/0x350
[   20.996576]  ? __pfx_worker_thread+0x10/0x10
[   20.996576]  kthread+0xe2/0x110
[   20.996576]  ? __pfx_kthread+0x10/0x10
[   20.996576]  ret_from_fork+0x34/0x50
[   20.996576]  ? __pfx_kthread+0x10/0x10
[   20.996576]  ret_from_fork_asm+0x1a/0x30
[   20.996576]  </TASK>
[   21.056592] sched_ext: BPF scheduler "simple" disabled (unregistered from user space)

Signed-off-by: Changwoo Min <changwoo@igalia.com>
Acked-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit cd38a8f)
Signed-off-by: John Stultz <jstultz@google.com>

btrfs_subpage_set_writeback() calls folio_start_writeback() the first time
a folio is written back, and it also clears the PAGECACHE_TAG_TOWRITE tag
even if there are still dirty blocks in the folio. This can break ordering
guarantees, such as those required by btrfs_wait_ordered_extents().

That ordering breakage leads to a real failure. For example, running
generic/464 on a zoned setup will hit the following ASSERT. This happens
because the broken ordering fails to flush existing dirty pages before the
file size is truncated.

  assertion failed: !list_empty(&ordered->list) :: 0, in fs/btrfs/zoned.c:1899
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/zoned.c:1899!
  Oops: invalid opcode: 0000 [#1] SMP NOPTI
  CPU: 2 UID: 0 PID: 1906169 Comm: kworker/u130:2 Kdump: loaded Not tainted 6.16.0-rc6-BTRFS-ZNS+ torvalds#554 PREEMPT(voluntary)
  Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021
  Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  RIP: 0010:btrfs_finish_ordered_zoned.cold+0x50/0x52 [btrfs]
  RSP: 0018:ffffc9002efdbd60 EFLAGS: 00010246
  RAX: 000000000000004c RBX: ffff88811923c4e0 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffffffff827e38b1 RDI: 00000000ffffffff
  RBP: ffff88810005d000 R08: 00000000ffffdfff R09: ffffffff831051c8
  R10: ffffffff83055220 R11: 0000000000000000 R12: ffff8881c2458c00
  R13: ffff88811923c540 R14: ffff88811923c5e8 R15: ffff8881c1bd9680
  FS:  0000000000000000(0000) GS:ffff88a04acd0000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f907c7a918c CR3: 0000000004024000 CR4: 0000000000350ef0
  Call Trace:
   <TASK>
   ? srso_return_thunk+0x5/0x5f
   btrfs_finish_ordered_io+0x4a/0x60 [btrfs]
   btrfs_work_helper+0xf9/0x490 [btrfs]
   process_one_work+0x204/0x590
   ? srso_return_thunk+0x5/0x5f
   worker_thread+0x1d6/0x3d0
   ? __pfx_worker_thread+0x10/0x10
   kthread+0x118/0x230
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x205/0x260
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>

Consider process A calling writepages() with WB_SYNC_NONE. In zoned mode or
for compressed writes, it locks several folios for delalloc and starts
writing them out. Let's call the last locked folio folio X. Suppose the
write range only partially covers folio X, leaving some pages dirty.
Process A calls btrfs_subpage_set_writeback() when building a bio. This
function call clears the TOWRITE tag of folio X, whose size = 8K and
the block size = 4K. It is following state.

   0     4K    8K
   |/////|/////|  (flag: DIRTY, tag: DIRTY)
   <-----> Process A will write this range.

Now suppose process B concurrently calls writepages() with WB_SYNC_ALL. It
calls tag_pages_for_writeback() to tag dirty folios with
PAGECACHE_TAG_TOWRITE. Since folio X is still dirty, it gets tagged. Then,
B collects tagged folios using filemap_get_folios_tag() and must wait for
folio X to be written before returning from writepages().

   0     4K    8K
   |/////|/////|  (flag: DIRTY, tag: DIRTY|TOWRITE)

However, between tagging and collecting, process A may call
btrfs_subpage_set_writeback() and clear folio X's TOWRITE tag.
   0     4K    8K
   |     |/////|  (flag: DIRTY|WRITEBACK, tag: DIRTY)

As a result, process B won't see folio X in its batch, and returns without
waiting for it. This breaks the WB_SYNC_ALL ordering requirement.

Fix this by using btrfs_subpage_set_writeback_keepwrite(), which retains
the TOWRITE tag. We now manually clear the tag only after the folio becomes
clean, via the xas operation.

Fixes: 3470da3 ("btrfs: subpage: introduce helpers for writeback status")
CC: stable@vger.kernel.org # 6.12+
Reviewed-by: Qu Wenruo <wqu@suse.com>
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>

An use-after-free issue occurred when __mark_inode_dirty() get the
bdi_writeback that was in the progress of switching.

CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1
......
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __mark_inode_dirty+0x124/0x418
lr : __mark_inode_dirty+0x118/0x418
sp : ffffffc08c9dbbc0
........
Call trace:
 __mark_inode_dirty+0x124/0x418
 generic_update_time+0x4c/0x60
 file_modified+0xcc/0xd0
 ext4_buffered_write_iter+0x58/0x124
 ext4_file_write_iter+0x54/0x704
 vfs_write+0x1c0/0x308
 ksys_write+0x74/0x10c
 __arm64_sys_write+0x1c/0x28
 invoke_syscall+0x48/0x114
 el0_svc_common.constprop.0+0xc0/0xe0
 do_el0_svc+0x1c/0x28
 el0_svc+0x40/0xe4
 el0t_64_sync_handler+0x120/0x12c
 el0t_64_sync+0x194/0x198

Root cause is:

systemd-random-seed                         kworker
----------------------------------------------------------------------
___mark_inode_dirty                     inode_switch_wbs_work_fn

  spin_lock(&inode->i_lock);
  inode_attach_wb
  locked_inode_to_wb_and_lock_list
     get inode->i_wb
     spin_unlock(&inode->i_lock);
     spin_lock(&wb->list_lock)
  spin_lock(&inode->i_lock)
  inode_io_list_move_locked
  spin_unlock(&wb->list_lock)
  spin_unlock(&inode->i_lock)
                                    spin_lock(&old_wb->list_lock)
                                      inode_do_switch_wbs
                                        spin_lock(&inode->i_lock)
                                        inode->i_wb = new_wb
                                        spin_unlock(&inode->i_lock)
                                    spin_unlock(&old_wb->list_lock)
                                    wb_put_many(old_wb, nr_switched)
                                      cgwb_release
                                      old wb released
  wb_wakeup_delayed() accesses wb,
  then trigger the use-after-free
  issue

Fix this race condition by holding inode spinlock until
wb_wakeup_delayed() finished.

Signed-off-by: Jiufei Xue <jiufei.xue@samsung.com>
Link: https://lore.kernel.org/20250728100715.3863241-1-jiufei.xue@samsung.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

…dlock

When a user creates a dualpi2 qdisc it automatically sets a timer. This
timer will run constantly and update the qdisc's probability field.
The issue is that the timer acquires the qdisc root lock and runs in
hardirq. The qdisc root lock is also acquired in dev.c whenever a packet
arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq,
it may interrupt the packet processing running in softirq. If that happens
and it runs on the same CPU, it will acquire the same lock and cause a
deadlock. The following splat shows up when running a kernel compiled with
lock debugging:

[  +0.000224] WARNING: inconsistent lock state
[  +0.000224] 6.16.0+ torvalds#10 Not tainted
[  +0.000169] --------------------------------
[  +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
[  +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes:
[  +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140
[  +0.000000] {IN-HARDIRQ-W} state was registered at:
[  +0.000000]   lock_acquire.part.0+0xb6/0x220
[  +0.000000]   _raw_spin_lock+0x31/0x80
[  +0.000000]   dualpi2_timer+0x6f/0x270
[  +0.000000]   __hrtimer_run_queues+0x1c5/0x360
[  +0.000000]   hrtimer_interrupt+0x115/0x260
[  +0.000000]   __sysvec_apic_timer_interrupt+0x6d/0x1a0
[  +0.000000]   sysvec_apic_timer_interrupt+0x6e/0x80
[  +0.000000]   asm_sysvec_apic_timer_interrupt+0x1a/0x20
[  +0.000000]   pv_native_safe_halt+0xf/0x20
[  +0.000000]   default_idle+0x9/0x10
[  +0.000000]   default_idle_call+0x7e/0x1e0
[  +0.000000]   do_idle+0x1e8/0x250
[  +0.000000]   cpu_startup_entry+0x29/0x30
[  +0.000000]   rest_init+0x151/0x160
[  +0.000000]   start_kernel+0x6f3/0x700
[  +0.000000]   x86_64_start_reservations+0x24/0x30
[  +0.000000]   x86_64_start_kernel+0xc8/0xd0
[  +0.000000]   common_startup_64+0x13e/0x148
[  +0.000000] irq event stamp: 6884
[  +0.000000] hardirqs last  enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270
[  +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270
[  +0.000000] softirqs last  enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270
[  +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140
[  +0.000000]
              other info that might help us debug this:
[  +0.000000]  Possible unsafe locking scenario:

[  +0.000000]        CPU0
[  +0.000000]        ----
[  +0.000000]   lock(&sch->root_lock_key);
[  +0.000000]   <Interrupt>
[  +0.000000]     lock(&sch->root_lock_key);
[  +0.000000]
               *** DEADLOCK ***

[  +0.000000] 4 locks held by ping/156:
[  +0.000000]  #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40
[  +0.000000]  #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190
[  +0.000000]  #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950
[  +0.000000]  #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140

I am able to reproduce it consistently when running the following:

tc qdisc add dev lo handle 1: root dualpi2
ping -f 127.0.0.1

To fix it, make the timer run in softirq.

Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc")
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

BPF CI testing report a UAF issue:

  [   16.446633] BUG: kernel NULL pointer dereference, address: 000000000000003  0
  [   16.447134] #PF: supervisor read access in kernel mod  e
  [   16.447516] #PF: error_code(0x0000) - not-present pag  e
  [   16.447878] PGD 0 P4D   0
  [   16.448063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPT  I
  [   16.448409] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Tainted: G           OE      6.13.0-rc3-g89e8a75fda73-dirty #4  2
  [   16.449124] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODUL  E
  [   16.449502] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/201  4
  [   16.450201] Workqueue: smc_hs_wq smc_listen_wor  k
  [   16.450531] RIP: 0010:smc_listen_work+0xc02/0x159  0
  [   16.452158] RSP: 0018:ffffb5ab40053d98 EFLAGS: 0001024  6
  [   16.452526] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000030  0
  [   16.452994] RDX: 0000000000000280 RSI: 00003513840053f0 RDI: 000000000000000  0
  [   16.453492] RBP: ffffa097808e3800 R08: ffffa09782dba1e0 R09: 000000000000000  5
  [   16.453987] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa0978274640  0
  [   16.454497] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa09782d4092  0
  [   16.454996] FS:  0000000000000000(0000) GS:ffffa097bbc00000(0000) knlGS:000000000000000  0
  [   16.455557] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003  3
  [   16.455961] CR2: 0000000000000030 CR3: 0000000102788004 CR4: 0000000000770ef  0
  [   16.456459] PKRU: 5555555  4
  [   16.456654] Call Trace  :
  [   16.456832]  <TASK  >
  [   16.456989]  ? __die+0x23/0x7  0
  [   16.457215]  ? page_fault_oops+0x180/0x4c  0
  [   16.457508]  ? __lock_acquire+0x3e6/0x249  0
  [   16.457801]  ? exc_page_fault+0x68/0x20  0
  [   16.458080]  ? asm_exc_page_fault+0x26/0x3  0
  [   16.458389]  ? smc_listen_work+0xc02/0x159  0
  [   16.458689]  ? smc_listen_work+0xc02/0x159  0
  [   16.458987]  ? lock_is_held_type+0x8f/0x10  0
  [   16.459284]  process_one_work+0x1ea/0x6d  0
  [   16.459570]  worker_thread+0x1c3/0x38  0
  [   16.459839]  ? __pfx_worker_thread+0x10/0x1  0
  [   16.460144]  kthread+0xe0/0x11  0
  [   16.460372]  ? __pfx_kthread+0x10/0x1  0
  [   16.460640]  ret_from_fork+0x31/0x5  0
  [   16.460896]  ? __pfx_kthread+0x10/0x1  0
  [   16.461166]  ret_from_fork_asm+0x1a/0x3  0
  [   16.461453]  </TASK  >
  [   16.461616] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE)  ]
  [   16.462134] CR2: 000000000000003  0
  [   16.462380] ---[ end trace 0000000000000000 ]---
  [   16.462710] RIP: 0010:smc_listen_work+0xc02/0x1590

The direct cause of this issue is that after smc_listen_out_connected(),
newclcsock->sk may be NULL since it will releases the smcsk. Therefore,
if the application closes the socket immediately after accept,
newclcsock->sk can be NULL. A possible execution order could be as
follows:

smc_listen_work                                 | userspace
-----------------------------------------------------------------
lock_sock(sk)                                   |
smc_listen_out_connected()                      |
| \- smc_listen_out                             |
|    | \- release_sock                          |
     | |- sk->sk_data_ready()                   |
                                                | fd = accept();
                                                | close(fd);
                                                |  \- socket->sk = NULL;
/* newclcsock->sk is NULL now */
SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk))

Since smc_listen_out_connected() will not fail, simply swapping the order
of the code can easily fix this issue.

Fixes: 3b2dec2 ("net/smc: restructure client and server code in af_smc")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/20250818054618.41615-1-alibuda@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Receiving HSR frame with insufficient space to hold HSR tag in the skb
can result in a crash (kernel BUG):

[   45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1
[   45.392559] ------------[ cut here ]------------
[   45.392912] kernel BUG at net/core/skbuff.c:211!
[   45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[   45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 torvalds#12 PREEMPT(undef)
[   45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   45.395273] RIP: 0010:skb_panic+0x15b/0x1d0

<snip registers, remove unreliable trace>

[   45.402911] Call Trace:
[   45.403105]  <IRQ>
[   45.404470]  skb_push+0xcd/0xf0
[   45.404726]  br_dev_queue_push_xmit+0x7c/0x6c0
[   45.406513]  br_forward_finish+0x128/0x260
[   45.408483]  __br_forward+0x42d/0x590
[   45.409464]  maybe_deliver+0x2eb/0x420
[   45.409763]  br_flood+0x174/0x4a0
[   45.410030]  br_handle_frame_finish+0xc7c/0x1bc0
[   45.411618]  br_handle_frame+0xac3/0x1230
[   45.413674]  __netif_receive_skb_core.constprop.0+0x808/0x3df0
[   45.422966]  __netif_receive_skb_one_core+0xb4/0x1f0
[   45.424478]  __netif_receive_skb+0x22/0x170
[   45.424806]  process_backlog+0x242/0x6d0
[   45.425116]  __napi_poll+0xbb/0x630
[   45.425394]  net_rx_action+0x4d1/0xcc0
[   45.427613]  handle_softirqs+0x1a4/0x580
[   45.427926]  do_softirq+0x74/0x90
[   45.428196]  </IRQ>

This issue was found by syzkaller.

The panic happens in br_dev_queue_push_xmit() once it receives a
corrupted skb with ETH header already pushed in linear data. When it
attempts the skb_push() call, there's not enough headroom and
skb_push() panics.

The corrupted skb is put on the queue by HSR layer, which makes a
sequence of unintended transformations when it receives a specific
corrupted HSR frame (with incomplete TAG).

Fix it by dropping and consuming frames that are not long enough to
contain both ethernet and hsr headers.

Alternative fix would be to check for enough headroom before skb_push()
in br_dev_queue_push_xmit().

In the reproducer, this is injected via AF_PACKET, but I don't easily
see why it couldn't be sent over the wire from adjacent network.

Further Details:

In the reproducer, the following network interface chain is set up:

┌────────────────┐   ┌────────────────┐
│ veth0_to_hsr   ├───┤  hsr_slave0    ┼───┐
└────────────────┘   └────────────────┘   │
                                          │ ┌──────┐
                                          ├─┤ hsr0 ├───┐
                                          │ └──────┘   │
┌────────────────┐   ┌────────────────┐   │            │┌────────┐
│ veth1_to_hsr   ┼───┤  hsr_slave1    ├───┘            └┤        │
└────────────────┘   └────────────────┘                ┌┼ bridge │
                                                       ││        │
                                                       │└────────┘
                                                       │
                                        ┌───────┐      │
                                        │  ...  ├──────┘
                                        └───────┘

To trigger the events leading up to crash, reproducer sends a corrupted
HSR frame with incomplete TAG, via AF_PACKET socket on 'veth0_to_hsr'.

The first HSR-layer function to process this frame is
hsr_handle_frame(). It and then checks if the
protocol is ETH_P_PRP or ETH_P_HSR. If it is, it calls
skb_set_network_header(skb, ETH_HLEN + HSR_HLEN), without checking that
the skb is long enough. For the crashing frame it is not, and hence the
skb->network_header and skb->mac_len fields are set incorrectly,
pointing after the end of the linear buffer.

I will call this a BUG#1 and it is what is addressed by this patch. In
the crashing scenario before the fix, the skb continues to go down the
hsr path as follows.

hsr_handle_frame() then calls this sequence
hsr_forward_skb()
  fill_frame_info()
    hsr->proto_ops->fill_frame_info()
      hsr_fill_frame_info()

hsr_fill_frame_info() contains a check that intends to check whether the
skb actually contains the HSR header. But the check relies on the
skb->mac_len field which was erroneously setup due to BUG#1, so the
check passes and the execution continues  back in the hsr_forward_skb():

hsr_forward_skb()
  hsr_forward_do()
    hsr->proto_ops->get_untagged_frame()
      hsr_get_untagged_frame()
        create_stripped_skb_hsr()

In create_stripped_skb_hsr(), a copy of the skb is created and is
further corrupted by operation that attempts to strip the HSR tag in a
call to __pskb_copy().

The skb enters create_stripped_skb_hsr() with ethernet header pushed in
linear buffer. The skb_pull(skb_in, HSR_HLEN) thus pulls 6 bytes of
ethernet header into the headroom, creating skb_in with a headroom of
size 8. The subsequent __pskb_copy() then creates an skb with headroom
of just 2 and skb->len of just 12, this is how it looks after the copy:

gdb) p skb->len
$10 = 12
(gdb) p skb->data
$11 = (unsigned char *) 0xffff888041e45382 "\252\252\252\252\252!\210\373",
(gdb) p skb->head
$12 = (unsigned char *) 0xffff888041e45380 ""

It seems create_stripped_skb_hsr() assumes that ETH header is pulled
in the headroom when it's entered, because it just pulls HSR header on
top. But that is not the case in our code-path and we end up with the
corrupted skb instead. I will call this BUG#2

*I got confused here because it seems that under no conditions can
create_stripped_skb_hsr() work well, the assumption it makes is not true
during the processing of hsr frames - since the skb_push() in
hsr_handle_frame to skb_pull in hsr_deliver_master(). I wonder whether I
missed something here.*

Next, the execution arrives in hsr_deliver_master(). It calls
skb_pull(ETH_HLEN), which just returns NULL - the SKB does not have
enough space for the pull (as it only has 12 bytes in total at this
point).

*The skb_pull() here further suggests that ethernet header is meant
to be pushed through the whole hsr processing and
create_stripped_skb_hsr() should pull it before doing the HSR header
pull.*

hsr_deliver_master() then puts the corrupted skb on the queue, it is
then picked up from there by bridge frame handling layer and finally
lands in br_dev_queue_push_xmit where it panics.

Cc: stable@kernel.org
Fixes: 48b491a ("net: hsr: fix mac_len checks")
Reported-by: syzbot+a81f2759d022496b40ab@syzkaller.appspotmail.com
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250819082842.94378-1-acsjakub@amazon.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The mm/debug_vm_pagetable test allocates manually page table entries for
the tests it runs, using also its manually allocated mm_struct.  That in
itself is ok, but when it exits, at destroy_args() it fails to clear those
entries with the *_clear functions.

The problem is that leaves stale entries.  If another process allocates an
mm_struct with a pgd at the same address, it may end up running into the
stale entry.  This is happening in practice on a debug kernel with
CONFIG_DEBUG_VM_PGTABLE=y, for example this is the output with some extra
debugging I added (it prints a warning trace if pgtables_bytes goes
negative, in addition to the warning at check_mm() function):

[    2.539353] debug_vm_pgtable: [get_random_vaddr         ]: random_vaddr is 0x7ea247140000
[    2.539366] kmem_cache info
[    2.539374] kmem_cachep 0x000000002ce82385 - freelist 0x0000000000000000 - offset 0x508
[    2.539447] debug_vm_pgtable: [init_args                ]: args->mm is 0x000000002267cc9e
(...)
[    2.552800] WARNING: CPU: 5 PID: 116 at include/linux/mm.h:2841 free_pud_range+0x8bc/0x8d0
[    2.552816] Modules linked in:
[    2.552843] CPU: 5 UID: 0 PID: 116 Comm: modprobe Not tainted 6.12.0-105.debug_vm2.el10.ppc64le+debug #1 VOLUNTARY
[    2.552859] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW910.00 (VL910_062) hv:phyp pSeries
[    2.552872] NIP:  c0000000007eef3c LR: c0000000007eef30 CTR: c0000000003d8c90
[    2.552885] REGS: c0000000622e73b0 TRAP: 0700   Not tainted  (6.12.0-105.debug_vm2.el10.ppc64le+debug)
[    2.552899] MSR:  800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 24002822  XER: 0000000a
[    2.552954] CFAR: c0000000008f03f0 IRQMASK: 0
[    2.552954] GPR00: c0000000007eef30 c0000000622e7650 c000000002b1ac00 0000000000000001
[    2.552954] GPR04: 0000000000000008 0000000000000000 c0000000007eef30 ffffffffffffffff
[    2.552954] GPR08: 00000000ffff00f5 0000000000000001 0000000000000048 0000000000004000
[    2.552954] GPR12: 00000003fa440000 c000000017ffa300 c0000000051d9f80 ffffffffffffffdb
[    2.552954] GPR16: 0000000000000000 0000000000000008 000000000000000a 60000000000000e0
[    2.552954] GPR20: 4080000000000000 c0000000113af038 00007fffcf130000 0000700000000000
[    2.552954] GPR24: c000000062a6a000 0000000000000001 8000000062a68000 0000000000000001
[    2.552954] GPR28: 000000000000000a c000000062ebc600 0000000000002000 c000000062ebc760
[    2.553170] NIP [c0000000007eef3c] free_pud_range+0x8bc/0x8d0
[    2.553185] LR [c0000000007eef30] free_pud_range+0x8b0/0x8d0
[    2.553199] Call Trace:
[    2.553207] [c0000000622e7650] [c0000000007eef30] free_pud_range+0x8b0/0x8d0 (unreliable)
[    2.553229] [c0000000622e7750] [c0000000007f40b4] free_pgd_range+0x284/0x3b0
[    2.553248] [c0000000622e7800] [c0000000007f4630] free_pgtables+0x450/0x570
[    2.553274] [c0000000622e78e0] [c0000000008161c0] exit_mmap+0x250/0x650
[    2.553292] [c0000000622e7a30] [c0000000001b95b8] __mmput+0x98/0x290
[    2.558344] [c0000000622e7a80] [c0000000001d1018] exit_mm+0x118/0x1b0
[    2.558361] [c0000000622e7ac0] [c0000000001d141c] do_exit+0x2ec/0x870
[    2.558376] [c0000000622e7b60] [c0000000001d1ca8] do_group_exit+0x88/0x150
[    2.558391] [c0000000622e7bb0] [c0000000001d1db8] sys_exit_group+0x48/0x50
[    2.558407] [c0000000622e7be0] [c00000000003d810] system_call_exception+0x1e0/0x4c0
[    2.558423] [c0000000622e7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
(...)
[    2.558892] ---[ end trace 0000000000000000 ]---
[    2.559022] BUG: Bad rss-counter state mm:000000002267cc9e type:MM_ANONPAGES val:1
[    2.559037] BUG: non-zero pgtables_bytes on freeing mm: -6144

Here the modprobe process ended up with an allocated mm_struct from the
mm_struct slab that was used before by the debug_vm_pgtable test.  That is
not a problem, since the mm_struct is initialized again etc., however, if
it ends up using the same pgd table, it bumps into the old stale entry
when clearing/freeing the page table entries, so it tries to free an entry
already gone (that one which was allocated by the debug_vm_pgtable test),
which also explains the negative pgtables_bytes since it's accounting for
not allocated entries in the current process.

As far as I looked pgd_{alloc,free} etc.  does not clear entries, and
clearing of the entries is explicitly done in the free_pgtables->
free_pgd_range->free_p4d_range->free_pud_range->free_pmd_range->
free_pte_range path.  However, the debug_vm_pgtable test does not call
free_pgtables, since it allocates mm_struct and entries manually for its
test and eg.  not goes through page faults.  So it also should clear
manually the entries before exit at destroy_args().

This problem was noticed on a reboot X number of times test being done on
a powerpc host, with a debug kernel with CONFIG_DEBUG_VM_PGTABLE enabled. 
Depends on the system, but on a 100 times reboot loop the problem could
manifest once or twice, if a process ends up getting the right mm->pgd
entry with the stale entries used by mm/debug_vm_pagetable.  After using
this patch, I couldn't reproduce/experience the problems anymore.  I was
able to reproduce the problem as well on latest upstream kernel (6.16).

I also modified destroy_args() to use mmput() instead of mmdrop(), there
is no reason to hold mm_users reference and not release the mm_struct
entirely, and in the output above with my debugging prints I already had
patched it to use mmput, it did not fix the problem, but helped in the
debugging as well.

Link: https://lkml.kernel.org/r/20250731214051.4115182-1-herton@redhat.com
Fixes: 3c9b84f ("mm/debug_vm_pgtable: introduce struct pgtable_debug_args")
Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service
routine to a threaded IRQ handler") introduced an IRQ lock inversion
issue. Fix this lock inversion by changing the spin_lock_irq() calls into
spin_lock_irqsave() calls in code that can be called either from
interrupt context or from thread context. This patch fixes the following
lockdep complaint:

WARNING: possible irq lock inversion dependency detected
6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G        W  OE
--------------------------------------------------------
kworker/u28:0/12 just changed the state of lock:
ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110
but this lock took another, HARDIRQ-unsafe lock in the past:
 (shost->host_lock){+.+.}-{2:2}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(shost->host_lock);
                               local_irq_disable();
                               lock(&hba->clk_gating.lock);
                               lock(shost->host_lock);
  <Interrupt>
    lock(&hba->clk_gating.lock);

 *** DEADLOCK ***

4 locks held by kworker/u28:0/12:
 #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
 #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
 #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120
 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104

the shortest dependencies between 2nd lock and 1st lock:
 -> (shost->host_lock){+.+.}-{2:2} {
    HARDIRQ-ON-W at:
                      lock_acquire+0x134/0x2b4
                      _raw_spin_lock+0x48/0x64
                      ufshcd_sl_intr+0x4c/0xa08
                      ufshcd_threaded_intr+0x70/0x12c
                      irq_thread_fn+0x48/0xa8
                      irq_thread+0x130/0x1ec
                      kthread+0x110/0x134
                      ret_from_fork+0x10/0x20
    SOFTIRQ-ON-W at:
                      lock_acquire+0x134/0x2b4
                      _raw_spin_lock+0x48/0x64
                      ufshcd_sl_intr+0x4c/0xa08
                      ufshcd_threaded_intr+0x70/0x12c
                      irq_thread_fn+0x48/0xa8
                      irq_thread+0x130/0x1ec
                      kthread+0x110/0x134
                      ret_from_fork+0x10/0x20
    INITIAL USE at:
                     lock_acquire+0x134/0x2b4
                     _raw_spin_lock+0x48/0x64
                     ufshcd_sl_intr+0x4c/0xa08
                     ufshcd_threaded_intr+0x70/0x12c
                     irq_thread_fn+0x48/0xa8
                     irq_thread+0x130/0x1ec
                     kthread+0x110/0x134
                     ret_from_fork+0x10/0x20
  }
  ... key      at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10
  ... acquired at:
   _raw_spin_lock_irqsave+0x5c/0x80
   __ufshcd_release+0x78/0x118
   ufshcd_send_uic_cmd+0xe4/0x118
   ufshcd_dme_set_attr+0x88/0x1c8
   ufs_google_phy_initialization+0x68/0x418 [ufs]
   ufs_google_link_startup_notify+0x78/0x27c [ufs]
   ufshcd_link_startup+0x84/0x720
   ufshcd_init+0xf3c/0x1330
   ufshcd_pltfrm_init+0x728/0x7d8
   ufs_google_probe+0x30/0x84 [ufs]
   platform_probe+0xa0/0xe0
   really_probe+0x114/0x454
   __driver_probe_device+0xa4/0x160
   driver_probe_device+0x44/0x23c
   __driver_attach_async_helper+0x60/0xd4
   async_run_entry_fn+0x4c/0x17c
   process_one_work+0x26c/0x65c
   worker_thread+0x33c/0x498
   kthread+0x110/0x134
   ret_from_fork+0x10/0x20

-> (&hba->clk_gating.lock){-...}-{2:2} {
   IN-HARDIRQ-W at:
                    lock_acquire+0x134/0x2b4
                    _raw_spin_lock_irqsave+0x5c/0x80
                    ufshcd_release_scsi_cmd+0x60/0x110
                    ufshcd_compl_one_cqe+0x2c0/0x3f4
                    ufshcd_mcq_poll_cqe_lock+0xb0/0x104
                    ufs_google_mcq_intr+0x80/0xa0 [ufs]
                    __handle_irq_event_percpu+0x104/0x32c
                    handle_irq_event+0x40/0x9c
                    handle_fasteoi_irq+0x170/0x2e8
                    generic_handle_domain_irq+0x58/0x80
                    gic_handle_irq+0x48/0x104
                    call_on_irq_stack+0x3c/0x50
                    do_interrupt_handler+0x7c/0xd8
                    el1_interrupt+0x34/0x58
                    el1h_64_irq_handler+0x18/0x24
                    el1h_64_irq+0x68/0x6c
                    _raw_spin_unlock_irqrestore+0x3c/0x6c
                    debug_object_assert_init+0x16c/0x21c
                    __mod_timer+0x4c/0x48c
                    schedule_timeout+0xd4/0x16c
                    io_schedule_timeout+0x48/0x70
                    do_wait_for_common+0x100/0x194
                    wait_for_completion_io_timeout+0x48/0x6c
                    blk_execute_rq+0x124/0x17c
                    scsi_execute_cmd+0x18c/0x3f8
                    scsi_probe_and_add_lun+0x204/0xd74
                    __scsi_add_device+0xbc/0x120
                    ufshcd_async_scan+0x80/0x3c0
                    async_run_entry_fn+0x4c/0x17c
                    process_one_work+0x26c/0x65c
                    worker_thread+0x33c/0x498
                    kthread+0x110/0x134
                    ret_from_fork+0x10/0x20
   INITIAL USE at:
                   lock_acquire+0x134/0x2b4
                   _raw_spin_lock_irqsave+0x5c/0x80
                   ufshcd_hold+0x34/0x14c
                   ufshcd_send_uic_cmd+0x28/0x118
                   ufshcd_dme_set_attr+0x88/0x1c8
                   ufs_google_phy_initialization+0x68/0x418 [ufs]
                   ufs_google_link_startup_notify+0x78/0x27c [ufs]
                   ufshcd_link_startup+0x84/0x720
                   ufshcd_init+0xf3c/0x1330
                   ufshcd_pltfrm_init+0x728/0x7d8
                   ufs_google_probe+0x30/0x84 [ufs]
                   platform_probe+0xa0/0xe0
                   really_probe+0x114/0x454
                   __driver_probe_device+0xa4/0x160
                   driver_probe_device+0x44/0x23c
                   __driver_attach_async_helper+0x60/0xd4
                   async_run_entry_fn+0x4c/0x17c
                   process_one_work+0x26c/0x65c
                   worker_thread+0x33c/0x498
                   kthread+0x110/0x134
                   ret_from_fork+0x10/0x20
 }
 ... key      at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10
 ... acquired at:
   mark_lock+0x1c4/0x224
   __lock_acquire+0x438/0x2e1c
   lock_acquire+0x134/0x2b4
   _raw_spin_lock_irqsave+0x5c/0x80
   ufshcd_release_scsi_cmd+0x60/0x110
   ufshcd_compl_one_cqe+0x2c0/0x3f4
   ufshcd_mcq_poll_cqe_lock+0xb0/0x104
   ufs_google_mcq_intr+0x80/0xa0 [ufs]
   __handle_irq_event_percpu+0x104/0x32c
   handle_irq_event+0x40/0x9c
   handle_fasteoi_irq+0x170/0x2e8
   generic_handle_domain_irq+0x58/0x80
   gic_handle_irq+0x48/0x104
   call_on_irq_stack+0x3c/0x50
   do_interrupt_handler+0x7c/0xd8
   el1_interrupt+0x34/0x58
   el1h_64_irq_handler+0x18/0x24
   el1h_64_irq+0x68/0x6c
   _raw_spin_unlock_irqrestore+0x3c/0x6c
   debug_object_assert_init+0x16c/0x21c
   __mod_timer+0x4c/0x48c
   schedule_timeout+0xd4/0x16c
   io_schedule_timeout+0x48/0x70
   do_wait_for_common+0x100/0x194
   wait_for_completion_io_timeout+0x48/0x6c
   blk_execute_rq+0x124/0x17c
   scsi_execute_cmd+0x18c/0x3f8
   scsi_probe_and_add_lun+0x204/0xd74
   __scsi_add_device+0xbc/0x120
   ufshcd_async_scan+0x80/0x3c0
   async_run_entry_fn+0x4c/0x17c
   process_one_work+0x26c/0x65c
   worker_thread+0x33c/0x498
   kthread+0x110/0x134
   ret_from_fork+0x10/0x20

stack backtrace:
CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G        W  OE      6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: async async_run_entry_fn
Call trace:
 dump_backtrace+0xfc/0x17c
 show_stack+0x18/0x28
 dump_stack_lvl+0x40/0xa0
 dump_stack+0x18/0x24
 print_irq_inversion_bug+0x2fc/0x304
 mark_lock_irq+0x388/0x4fc
 mark_lock+0x1c4/0x224
 __lock_acquire+0x438/0x2e1c
 lock_acquire+0x134/0x2b4
 _raw_spin_lock_irqsave+0x5c/0x80
 ufshcd_release_scsi_cmd+0x60/0x110
 ufshcd_compl_one_cqe+0x2c0/0x3f4
 ufshcd_mcq_poll_cqe_lock+0xb0/0x104
 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a]
 __handle_irq_event_percpu+0x104/0x32c
 handle_irq_event+0x40/0x9c
 handle_fasteoi_irq+0x170/0x2e8
 generic_handle_domain_irq+0x58/0x80
 gic_handle_irq+0x48/0x104
 call_on_irq_stack+0x3c/0x50
 do_interrupt_handler+0x7c/0xd8
 el1_interrupt+0x34/0x58
 el1h_64_irq_handler+0x18/0x24
 el1h_64_irq+0x68/0x6c
 _raw_spin_unlock_irqrestore+0x3c/0x6c
 debug_object_assert_init+0x16c/0x21c
 __mod_timer+0x4c/0x48c
 schedule_timeout+0xd4/0x16c
 io_schedule_timeout+0x48/0x70
 do_wait_for_common+0x100/0x194
 wait_for_completion_io_timeout+0x48/0x6c
 blk_execute_rq+0x124/0x17c
 scsi_execute_cmd+0x18c/0x3f8
 scsi_probe_and_add_lun+0x204/0xd74
 __scsi_add_device+0xbc/0x120
 ufshcd_async_scan+0x80/0x3c0
 async_run_entry_fn+0x4c/0x17c
 process_one_work+0x26c/0x65c
 worker_thread+0x33c/0x498
 kthread+0x110/0x134
 ret_from_fork+0x10/0x20

Cc: Neil Armstrong <neil.armstrong@linaro.org>
Cc: André Draszik <andre.draszik@linaro.org>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

These iterations require the read lock, otherwise RCU
lockdep will splat:

=============================
WARNING: suspicious RCU usage
6.17.0-rc3-00014-g31419c045d64 torvalds#6 Tainted: G           O
-----------------------------
drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
5 locks held by rtcwake/547:
 #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a
 #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b
 #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b
 #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b
 #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98

stack backtrace:
CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G           O        6.17.0-rc3-00014-g31419c045d64 torvalds#6 VOLUNTARY
Tainted: [O]=OOT_MODULE
Stack:
 223721b3a80 6089eac6 00000001 00000001
 ffffff00 6089eac6 00000535 6086e528
 721b3ac0 6003c294 00000000 60031fc0
Call Trace:
 [<600407ed>] show_stack+0x10e/0x127
 [<6003c294>] dump_stack_lvl+0x77/0xc6
 [<6003c2fd>] dump_stack+0x1a/0x20
 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e
 [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e
 [<603d980f>] device_suspend+0x528/0x541
 [<603da24b>] dpm_suspend+0x1a2/0x267
 [<603da837>] dpm_suspend_start+0x5d/0x72
 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736
 [...]

Add the fourth argument to the iteration to annotate
this and avoid the splat.

Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents")
Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

syzbot reported the splat below. [0]

When atmtcp_v_open() or atmtcp_v_close() is called via connect()
or close(), atmtcp_send_control() is called to send an in-kernel
special message.

The message has ATMTCP_HDR_MAGIC in atmtcp_control.hdr.length.
Also, a pointer of struct atm_vcc is set to atmtcp_control.vcc.

The notable thing is struct atmtcp_control is uAPI but has a
space for an in-kernel pointer.

  struct atmtcp_control {
  	struct atmtcp_hdr hdr;	/* must be first */
  ...
  	atm_kptr_t vcc;		/* both directions */
  ...
  } __ATM_API_ALIGN;

  typedef struct { unsigned char _[8]; } __ATM_API_ALIGN atm_kptr_t;

The special message is processed in atmtcp_recv_control() called
from atmtcp_c_send().

atmtcp_c_send() is vcc->dev->ops->send() and called from 2 paths:

  1. .ndo_start_xmit() (vcc->send() == atm_send_aal0())
  2. vcc_sendmsg()

The problem is sendmsg() does not validate the message length and
userspace can abuse atmtcp_recv_control() to overwrite any kptr
by atmtcp_control.

Let's add a new ->pre_send() hook to validate messages from sendmsg().

[0]:
Oops: general protection fault, probably for non-canonical address 0xdffffc00200000ab: 0000 [#1] SMP KASAN PTI
KASAN: probably user-memory-access in range [0x0000000100000558-0x000000010000055f]
CPU: 0 UID: 0 PID: 5865 Comm: syz-executor331 Not tainted 6.17.0-rc1-syzkaller-00215-gbab3ce404553 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:atmtcp_recv_control drivers/atm/atmtcp.c:93 [inline]
RIP: 0010:atmtcp_c_send+0x1da/0x950 drivers/atm/atmtcp.c:297
Code: 4d 8d 75 1a 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 15 06 00 00 41 0f b7 1e 4d 8d b7 60 05 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 13 06 00 00 66 41 89 1e 4d 8d 75 1c 4c
RSP: 0018:ffffc90003f5f810 EFLAGS: 00010203
RAX: 00000000200000ab RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88802a510000 RSI: 00000000ffffffff RDI: ffff888030a6068c
RBP: ffff88802699fb40 R08: ffff888030a606eb R09: 1ffff1100614c0dd
R10: dffffc0000000000 R11: ffffffff8718fc40 R12: dffffc0000000000
R13: ffff888030a60680 R14: 000000010000055f R15: 00000000ffffffff
FS:  00007f8d7e9236c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000045ad50 CR3: 0000000075bde000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 vcc_sendmsg+0xa10/0xc60 net/atm/common.c:645
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d7e96a4a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8d7e923198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8d7e9f4308 RCX: 00007f8d7e96a4a9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000005
RBP: 00007f8d7e9f4300 R08: 65732f636f72702f R09: 65732f636f72702f
R10: 65732f636f72702f R11: 0000000000000246 R12: 00007f8d7e9c10ac
R13: 00007f8d7e9231a0 R14: 0000200000000200 R15: 0000200000000250
 </TASK>
Modules linked in:

Fixes: 1da177e ("Linux-2.6.12-rc2")
Reported-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/68a6767c.050a0220.3d78fd.0011.GAE@google.com/
Tested-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250821021901.2814721-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

If preparing a write bio fails then blk_zone_wplug_bio_work() calls
bio_endio() with zwplug->lock held. If a device mapper driver is stacked
on top of the zoned block device then this results in nested locking of
zwplug->lock. The resulting lockdep complaint is a false positive
because this is nested locking and not recursive locking. Suppress this
false positive by calling blk_zone_wplug_bio_io_error() without holding
zwplug->lock. This is safe because no code in
blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This
patch suppresses the following lockdep complaint:

WARNING: possible recursive locking detected
--------------------------------------------
kworker/3:0H/46 is trying to acquire lock:
ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0

but task is already holding lock:
ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&zwplug->lock);
  lock(&zwplug->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by kworker/3:0H/46:
 #0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
 #1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
 #2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c

stack backtrace:
CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G        W  OE      6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: sdd_zwplugs blk_zone_wplug_bio_work
Call trace:
 dump_backtrace+0xfc/0x17c
 show_stack+0x18/0x28
 dump_stack_lvl+0x40/0xa0
 dump_stack+0x18/0x24
 print_deadlock_bug+0x38c/0x398
 __lock_acquire+0x13e8/0x2e1c
 lock_acquire+0x134/0x2b4
 _raw_spin_lock_irqsave+0x5c/0x80
 blk_zone_write_plug_bio_endio+0x64/0x1f0
 bio_endio+0x9c/0x240
 __dm_io_complete+0x214/0x260
 clone_endio+0xe8/0x214
 bio_endio+0x218/0x240
 blk_zone_wplug_bio_work+0x204/0x48c
 process_one_work+0x26c/0x65c
 worker_thread+0x33c/0x498
 kthread+0x110/0x134
 ret_from_fork+0x10/0x20

Cc: stable@vger.kernel.org
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Fixes: dd291d7 ("block: Introduce zone write plugging")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250825182720.1697203-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

 into HEAD

KVM/riscv fixes for 6.17, take #1

- Fix pte settings within kvm_riscv_gstage_ioremap()
- Fix comments in kvm_riscv_check_vcpu_requests()
- Fix stack overrun when setting vlenb via ONE_REG

commit c652887 ("KVM: arm64: vgic-v3: Allow userspace to write
GICD_TYPER2.nASSGIcap") makes the allocation of vPEs depend on nASSGIcap
for GICv4.1 hosts. While the vGIC v4 initialization and teardown is
handled correctly, it erroneously attempts to establish a vLPI mapping
to a VM that has no vPEs allocated:

  Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a8
   Mem abort info:
     ESR = 0x0000000096000044
     EC = 0x25: DABT (current EL), IL = 32 bits
     SET = 0, FnV = 0
     EA = 0, S1PTW = 0
     FSC = 0x04: level 0 translation fault
   Data abort info:
     ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
     CM = 0, WnR = 1, TnD = 0, TagAccess = 0
     GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
   user pgtable: 4k pages, 48-bit VAs, pgdp=00000073a453b000
   [00000000000000a8] pgd=0000000000000000, p4d=0000000000000000
   Internal error: Oops: 0000000096000044 [#1] SMP
   pstate: 23400009 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
   pc : its_irq_set_vcpu_affinity+0x58c/0x95c
   lr : its_irq_set_vcpu_affinity+0x1e0/0x95c
   sp : ffff8001029bb9e0
   pmr_save: 00000060
   x29: ffff8001029bba20 x28: ffff0001ca5e28c0 x27: 0000000000000000
   x26: 0000000000000000 x25: ffff00019eee9f80 x24: ffff0001992b3f00
   x23: ffff8001029bbab8 x22: ffff00001159fb80 x21: 00000000000024a7
   x20: 00000000000024a7 x19: ffff00019eee9fb4 x18: 0000000000000494
   x17: 000000000000000e x16: 0000000000000494 x15: 0000000000000002
   x14: ffff0001a7f34600 x13: ffffccaad1203000 x12: 0000000000000018
   x11: ffff000011991000 x10: 0000000000000000 x9 : 00000000000000a2
   x8 : 00000000000020a8 x7 : 0000000000000000 x6 : 000000000000003f
   x5 : 0000000000000040 x4 : 0000000000000000 x3 : 0000000000000004
   x2 : 0000000000000000 x1 : ffff8001029bbab8 x0 : 00000000000000a8
   Call trace:
    its_irq_set_vcpu_affinity+0x58c/0x95c
    irq_set_vcpu_affinity+0x74/0xc8
    its_map_vlpi+0x4c/0x94
    kvm_vgic_v4_set_forwarding+0x134/0x298
    kvm_arch_irq_bypass_add_producer+0x28/0x34
    irq_bypass_register_producer+0xf8/0x1d8
    vfio_msi_set_vector_signal+0x2c8/0x308
    vfio_pci_set_msi_trigger+0x198/0x2d4
    vfio_pci_set_irqs_ioctl+0xf0/0x104
    vfio_pci_core_ioctl+0x6ac/0xc5c
    vfio_device_fops_unl_ioctl+0x128/0x370
    __arm64_sys_ioctl+0x98/0xd0
    el0_svc_common+0xd8/0x1d8
    do_el0_svc+0x28/0x34
    el0_svc+0x40/0xb8
    el0t_64_sync_handler+0x70/0xbc
    el0t_64_sync+0x1a8/0x1ac
   Code: 321f0129 f940094a 8b08014 d1400900 (39000009)
   ---[ end trace 0000000000000000 ]---

Fix it by moving the GICv4.1 special-casing to
vgic_supports_direct_msis(), returning false if the user explicitly
disabled nASSGIcap for the VM.

Fixes: c652887 ("KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap")
Suggested-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Link: https://lore.kernel.org/r/20250729210644.830364-1-rananta@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if:

 1) a phandle in the "cpus" property does not correspond to a valid OF
    node
 2  a CPU logical id does not exist for a given OF cpu_node

#1 is a firmware bug and should be reported as such but does not warrant a
   WARN_ON() backtrace.

#2 is not necessarily an error condition (eg a kernel can be booted with
   nr_cpus=X limiting the number of cores artificially) and therefore there
   is no reason to clutter the kernel log with WARN_ON() output when the
   condition is hit.

Rework the IRS affinity parsing code to remove undue WARN_ON()s thus
making it less noisy.

Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250814094138.1611017-1-lpieralisi@kernel.org