INFO: task udevd:4981 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:26568 pid:4981 tgid:4981 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
bdev_open+0x41a/0xe40 block/bdev.c:953
blkdev_open+0x34e/0x4f0 block/fops.c:697
do_dentry_open+0x6d8/0x1660 fs/open.c:947
vfs_open+0x82/0x3f0 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x208c/0x31a0 fs/namei.c:4858
do_file_open+0x20e/0x430 fs/namei.c:4887
do_sys_openat2+0x10d/0x1e0 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0x860 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9aebdc5407
RSP: 002b:00007ffda910e6a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9aeb799880 RCX: 00007f9aebdc5407
RDX: 00000000000a0800 RSI: 00005625bb012240 RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00005625a0f6f100 R14: 0000000000000000 R15: 00007ffda910e930
INFO: task syz.0.17:5866 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:26776 pid:5866 tgid:5866 ppid:5764 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
bdev_release+0x15a/0x6d0 block/bdev.c:1136
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x3ff/0xb50 fs/file_table.c:510
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x107/0x4f0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x706/0x860 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff724b9ce59
RSP: 002b:00007fffffee5f18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ff724e17da0 RCX: 00007ff724b9ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007ff724e17da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007ff724e17cb0 R11: 0000000000000246 R12: 0000000000025e00
R13: 00007ff724e15fac R14: 0000000000025b22 R15: 00007fffffee6020
INFO: task syz.0.17:5867 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:27832 pid:5867 tgid:5866 ppid:5764 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
bdev_release+0x15a/0x6d0 block/bdev.c:1136
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x3ff/0xb50 fs/file_table.c:510
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x107/0x4f0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x706/0x860 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff724b9ce59
RSP: 002b:00007ff725b36028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007ff724e15fa0 RCX: 00007ff724b9ce59
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 00007ff724c32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff724e16038 R14: 00007ff724e15fa0 R15: 00007fffffee5db8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e7e5620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/35:
#0: ffff8880b853b2a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:652
#1: ffffc90000ab7d08 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffffffff8e67c6f0 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x12/0x20 kernel/jump_label.c:222
#3: ffffffff8e9295c0 (jump_label_mutex){+.+.}-{4:4}, at: jump_label_lock kernel/jump_label.c:27 [inline]
#3: ffffffff8e9295c0 (jump_label_mutex){+.+.}-{4:4}, at: static_key_disable_cpuslocked+0x110/0x1c0 kernel/jump_label.c:238
1 lock held by udevd/4981:
#0: ffff888027b8b350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953
2 locks held by getty/5369:
#0: ffff888037f770a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5650:
#0: ffff888027b8b350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953
1 lock held by syz.0.17/5866:
#0: ffff888027b8b350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1136
1 lock held by syz.0.17/5867:
#0: ffff888027b8b350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1136
3 locks held by syz.1.176/6263:
#0: ffff888027b16a60 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x155/0xd30 drivers/block/nbd.c:1656
#1: ffff888027b2b840 (&q->q_usage_counter(io)#50){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:206
#2: ffff888027b2b878 (&q->q_usage_counter(queue)#34){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:206
1 lock held by syz.1.176/6264:
#0: ffff888027b16a60 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x155/0xd30 drivers/block/nbd.c:1656
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6262 Comm: syz.1.176 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:write_comp_data+0x40/0x90 kernel/kcov.c:246
Code: 02 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 c3 cc cc cc cc 8b 87 d4 16 00 00 85 c0 74 f1 8b 87 b0 16 00 00 <83> f8 03 75 e6 48 8b 87 b8 16 00 00 8b bf b4 16 00 00 48 8b 30 48
RSP: 0018:ffffc9000514fe50 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff92000a29fce RCX: ffffffff81f78520
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802916ca00
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007ffd3f6e85f0
R13: 0000000000000000 R14: 0000000000000000 R15: 00000000000000e6
FS: 000055558fce2500(0000) GS:ffff88812446a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f39111ea540 CR3: 0000000059cc5000 CR4: 00000000003526f0
Call Trace:
clockid_to_kclock kernel/time/posix-timers.c:1530 [inline]
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1372 [inline]
__se_sys_clock_nanosleep kernel/time/posix-timers.c:1368 [inline]
__x64_sys_clock_nanosleep+0x100/0x480 kernel/time/posix-timers.c:1368
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0x860 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f391115d68e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffd3f6e8598 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055558fce2500 RCX: 00007f391115d68e
RDX: 00007ffd3f6e85f0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f3911417da0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000004b0ad
R13: 00007f391141609c R14: 000000000004add4 R15: 00007ffd3f6e8720