INFO: task udevd:5227 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23432 pid:5227 tgid:5227 ppid:1 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
bdev_open+0xe0/0xd30 block/bdev.c:945
blkdev_open+0x3a8/0x510 block/fops.c:691
do_dentry_open+0x953/0x13f0 fs/open.c:965
vfs_open+0x3b/0x340 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1461
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: 0033:0x7efc39aa7407
RSP: 002b:00007ffc647dc0f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007efc3a1f6880 RCX: 00007efc39aa7407
RDX: 00000000000a0800 RSI: 00005619d7514b50 RDI: ffffffffffffff9c
RBP: 00000000000000dc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00005619d3ac4100 R14: 0000000000000000 R15: 00007ffc647dc380
INFO: task syz.4.693:9260 blocked for more than 146 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.693 state:D stack:25128 pid:9260 tgid:9259 ppid:5856 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
bdev_release+0x1a9/0x650 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:699
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
get_signal+0x11ed/0x1340 kernel/signal.c:2807
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
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/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff92eb8ebe9
RSP: 002b:00007ff92f9ee038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007ff92edb5fa0 RCX: 00007ff92eb8ebe9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007ff92ec11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff92edb6038 R14: 00007ff92edb5fa0 R15: 00007ffc613e7288
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by udevd/5227:
#0: ffff888024e7f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by getty/5620:
#0: ffff88814da520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5925:
#0: ffff888024e7f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz.4.693/9260:
#0: ffff888024e7f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1128
=============================================
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 07/12/2025
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:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:_static_cpu_has arch/x86/include/asm/cpufeature.h:101 [inline]
RIP: 0010:addr_has_metadata mm/kasan/kasan.h:334 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:177 [inline]
RIP: 0010:kasan_check_range+0x30/0x2c0 mm/kasan/generic.c:189
Code: 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f 82 82 02 00 00 49 b9 00 00 00 00 00 80 ff ff 11 cc cc cc f3 0f 1e fa 49 b9 00 00 00 00 00 00 00 ff f3 0f 1e
RSP: 0018:ffffc900001277e8 EFLAGS: 00000202
RAX: ffffffff85522801 RBX: 0000000000000040 RCX: ffffffff85522858
RDX: 0000000000000001 RSI: 0000000000000040 RDI: ffffc90000127860
RBP: 0000000000000000 R08: ffffc900001278a0 R09: ffff800000000000
R10: dffffc0000000000 R11: ffffed100c327412 R12: 1ffff92000024f08
R13: ffffc900001278c0 R14: ffffc90000127860 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555951d35c8 CR3: 0000000011701000 CR4: 0000000000350ef0
Call Trace:
__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
_get_random_bytes+0xa8/0x210 drivers/char/random.c:398
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:790 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x69e/0xb80 drivers/net/netdevsim/dev.c:866
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245