INFO: task udevd:5168 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:23080 pid:5168 tgid:5168 ppid:1 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
bdev_open+0xe0/0xcc0 block/bdev.c:945
blkdev_open+0x46c/0x610 block/fops.c:701
do_dentry_open+0x9b1/0x1350 fs/open.c:965
vfs_open+0x3b/0x350 fs/open.c:1097
do_open fs/namei.c:3975 [inline]
path_openat+0x2ef1/0x3840 fs/namei.c:4134
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f417a66d407
RSP: 002b:00007ffdff3bb9e0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f417a57f880 RCX: 00007f417a66d407
RDX: 00000000000a0800 RSI: 0000559415ee5a30 RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00005593dee19100 R14: 0000000000000000 R15: 00007ffdff3bbc70
INFO: task syz.4.868:8602 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.868 state:D stack:28232 pid:8602 tgid:8601 ppid:5806 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2b1/0x6e0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:536 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:547
bdev_release+0x1af/0x660 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:709
__fput+0x45b/0xa80 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde0663f6c9
RSP: 002b:00007fde048a6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fde06895fa0 RCX: 00007fde0663f6c9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fde066c1f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fde06896038 R14: 00007fde06895fa0 R15: 00007ffc0a3093c8
Showing all locks held in the system:
3 locks held by kworker/1:0/31:
#0: ffff888019eda938 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888019eda938 ((wq_completion)pm){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc90000a5fba0 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc90000a5fba0 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff888027a65188 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#2: ffff888027a65188 (&dev->mutex){....}-{4:4}, at: usb_remote_wakeup+0x23/0x100 drivers/usb/core/hub.c:3885
1 lock held by khungtaskd/38:
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by udevd/5168:
#0: ffff88802478c4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
2 locks held by getty/5563:
#0: ffff88823bf2e8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/7849:
#0: ffff88802478c4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:945
1 lock held by syz.4.868/8602:
#0: ffff88802478c4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1af/0x660 block/bdev.c:1128
1 lock held by syz.3.1973/11371:
#0: ffff88803600c858 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x2e/0x450 fs/splice.c:1289
1 lock held by syz.0.1984/11391:
4 locks held by syz.1.1985/11394:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11394 Comm: syz.1.1985 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x6c/0x80 kernel/kcov.c:235
Code: f0 15 00 00 83 fa 02 75 21 48 8b 91 f8 15 00 00 48 8b 32 48 8d 7e 01 8b 89 f4 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cf 6e 05 09 cc 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90
RSP: 0018:ffffc9000e367508 EFLAGS: 00000287
RAX: ffffffff81fba010 RBX: ffff88813fffb740 RCX: 0000000000080000
RDX: ffffc9001ea21000 RSI: 0000000000029598 RDI: 0000000000029599
RBP: 1ffffd40002fb180 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff940002fb189 R12: ffff888019ebcf48
R13: ffffea00017d8c00 R14: ffffc9000e367578 R15: 1ffff92001c6ceaf
FS: 00007fad2a7966c0(0000) GS:ffff888126df9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f91fff8 CR3: 000000005983c000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
lruvec_memcg include/linux/memcontrol.h:851 [inline]
folio_matches_lruvec include/linux/memcontrol.h:1544 [inline]
folio_lruvec_relock_irqsave+0x100/0x510 include/linux/memcontrol.h:1566
folio_batch_move_lru+0x19d/0x330 mm/swap.c:171
__folio_batch_add_and_move+0x447/0xa90 mm/swap.c:196
shmem_alloc_and_add_folio mm/shmem.c:1969 [inline]
shmem_get_folio_gfp+0xb56/0x1a70 mm/shmem.c:2533
shmem_fault+0x170/0x380 mm/shmem.c:2734
__do_fault+0x138/0x390 mm/memory.c:5280
do_read_fault mm/memory.c:5698 [inline]
do_fault mm/memory.c:5832 [inline]
do_pte_missing mm/memory.c:4361 [inline]
handle_pte_fault mm/memory.c:6177 [inline]
__handle_mm_fault mm/memory.c:6318 [inline]
handle_mm_fault+0x23c6/0x3400 mm/memory.c:6487
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x1685/0x2860 mm/gup.c:1428
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860
__mm_populate+0x24c/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3471 [inline]
vm_mmap_pgoff+0x38a/0x4d0 mm/util.c:586
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad2c52f6c9
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:00007fad2a796038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fad2c785fa0 RCX: 00007fad2c52f6c9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007fad2c5b1f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad2c786038 R14: 00007fad2c785fa0 R15: 00007fff3f8001b8
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun