INFO: task syz-executor.0:6225 blocked for more than 143 seconds.
Not tainted 6.16.0-rc5-next-20250711-syzkaller-09053-ga62b7a37e6fc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:27240 pid:6225 tgid:6224 ppid:6172 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6847
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
bdev_release+0x1a9/0x650 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:684
__fput+0x44c/0xa70 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+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [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: 0033:0x7f56fe079b29
RSP: 002b:00007f56ff13f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f56fe18bf80 RCX: 00007f56fe079b29
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f56fe0d5326 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f56fe18bf80 R15: 00007ffc568c7838
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
1 lock held by klogd/5209:
#0: ffff8880b8739fd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by getty/5616:
#0: ffff88802feeb0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/6156:
#0: ffff888025003358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz-executor.0/6225:
#0: ffff888025003358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1128
1 lock held by syz-executor.0/6549:
#0: ffff888025003358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz-executor.0/6573:
#0: ffff888025003358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-next-20250711-syzkaller-09053-ga62b7a37e6fc #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0xfee/0x1030 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 3547 Comm: kworker/u8:8 Not tainted 6.16.0-rc5-next-20250711-syzkaller-09053-ga62b7a37e6fc #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:mark_lock+0xa0/0x190 kernel/locking/lockdep.c:4777
Code: c7 c7 31 67 ba 8d 48 c7 c6 e6 be a9 8d e8 38 ac e5 ff 90 0f 0b 90 90 90 31 c9 4c 89 fe 4c 89 f7 b8 01 00 00 00 85 69 60 74 10 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 49 89 fe 49 89 f7
RSP: 0018:ffffc9000cba71f8 EFLAGS: 00000006
RAX: 0000000000000001 RBX: 0000000000000008 RCX: ffffffff934ebb78
RDX: 0000000000000008 RSI: ffff888030ca2968 RDI: ffff888030ca1e00
RBP: 0000000000000100 R08: 0000000000000000 R09: ffffffff81add5ab
R10: dffffc0000000000 R11: fffffbfff1f47767 R12: 0000000000000002
R13: 0000000000000002 R14: ffff888030ca2968 R15: ffff888030ca2988
FS: 0000000000000000(0000) GS:ffff888125cc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559974318168 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
mark_usage kernel/locking/lockdep.c:4677 [inline]
__lock_acquire+0x6a8/0xd20 kernel/locking/lockdep.c:5194
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
lock_hrtimer_base kernel/time/hrtimer.c:171 [inline]
hrtimer_try_to_cancel+0x22b/0x420 kernel/time/hrtimer.c:1362
update_curr_dl_se+0x1ef/0x980 kernel/sched/deadline.c:1463
update_curr+0x3ba/0x8b0 kernel/sched/fair.c:1243
dequeue_entity+0x27/0x1690 kernel/sched/fair.c:5384
dequeue_entities+0x1fa/0x1510 kernel/sched/fair.c:6990
dequeue_task_fair+0x205/0x580 kernel/sched/fair.c:7089
block_task kernel/sched/core.c:2119 [inline]
try_to_block_task kernel/sched/core.c:6530 [inline]
__schedule+0x5a7/0x4d00 kernel/sched/core.c:6646
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
toggle_allocation_gate+0x159/0x240 mm/kfence/core.c:852
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245