INFO: task udevd:5877 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:21288 pid:5877 tgid:5877 ppid:5198 task_flags:0x400140 flags:0x00080802
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
io_schedule+0x80/0xd0 kernel/sched/core.c:7789
folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323
folio_put_wait_locked mm/filemap.c:1487 [inline]
do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4078
read_mapping_folio include/linux/pagemap.h:1017 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:722
adfspart_check_POWERTEC+0x8c/0xf30 block/partitions/acorn.c:454
check_partition block/partitions/core.c:141 [inline]
blk_add_partitions block/partitions/core.c:589 [inline]
bdev_disk_changed+0x75f/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:765
bdev_open+0x31e/0xd30 block/bdev.c:974
blkdev_open+0x457/0x600 block/fops.c:698
do_dentry_open+0x7ce/0x1420 fs/open.c:962
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x340e/0x3dd0 fs/namei.c:4787
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4c5f2a7407
RSP: 002b:00007ffdea686060 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f4c5f9f2880 RCX: 00007f4c5f2a7407
RDX: 00000000000a0800 RSI: 0000555ca63de1f0 RDI: ffffffffffffff9c
RBP: 0000555ca63c3910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000555ca63ea860
R13: 0000555ca63d1190 R14: 0000000000000000 R15: 0000555ca63ea860
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:3/50:
2 locks held by getty/5587:
#0: ffff888031bb10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by udevd/5877:
#0: ffff888025c00358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5180 Comm: syslogd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:unwind_next_frame+0x4a5/0x23d0 arch/x86/kernel/unwind_orc.c:520
Code: e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6d 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 80 18 00 00 41 0f b6 44 24 01 <83> e0 07 0f 84 6d 15 00 00 83 f8 01 4c 8b 7c 24 50 48 bd 00 00 00
RSP: 0018:ffffc900034673b8 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff8f99cb7c RCX: ffffffff8f99cb80
RDX: ffffffff90151f3c RSI: ffffffff90151f0c RDI: ffffffff8bc08300
RBP: dffffc0000000000 R08: 0000000000000009 R09: ffffffff8df41a20
R10: ffffc900034674e8 R11: fffff5200068cea9 R12: ffffffff90151f40
R13: ffffffff90151f41 R14: ffffc900034674e8 R15: ffffffff8f99cb7c
FS: 00007f92e02b9c80(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000000c6 CR3: 0000000032468000 CR4: 00000000003526f0
Call Trace:
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6668 [inline]
kfree+0x1c0/0x660 mm/slub.c:6876
skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1107
skb_release_all net/core/skbuff.c:1182 [inline]
__kfree_skb net/core/skbuff.c:1196 [inline]
consume_skb+0x9e/0xf0 net/core/skbuff.c:1428
__unix_dgram_recvmsg+0x9f9/0xd60 net/unix/af_unix.c:2658
sock_recvmsg_nosec net/socket.c:1078 [inline]
sock_recvmsg+0x22c/0x270 net/socket.c:1100
sock_read_iter+0x231/0x2f0 net/socket.c:1170
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x55a/0xa30 fs/read_write.c:572
ksys_read+0x145/0x250 fs/read_write.c:715
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f92e0409407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fffc4c97c30 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f92e02b9c80 RCX: 00007f92e0409407
RDX: 00000000000000ff RSI: 0000558ea6c95950 RDI: 0000000000000000
RBP: 0000558ea6c95910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000558ea6c95999
R13: 0000000000000000 R14: 0000558ea6c95950 R15: 0000558e8af00d98