INFO: task syz.6.668:8391 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.668 state:D stack:25672 pid:8391 tgid:8390 ppid:6032 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
sync_bdevs+0x1ac/0x340 block/bdev.c:1288
ksys_sync+0xb9/0x150 fs/sync.c:105
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
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: 0033:0x7eff0c98e929
RSP: 002b:00007eff0d74a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007eff0cbb5fa0 RCX: 00007eff0c98e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007eff0cbb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007eff0cbb5fa0 R15: 00007ffd36905038
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/u8:3/49:
4 locks held by kworker/u8:4/63:
2 locks held by getty/5609:
#0: ffff888030ded0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by kworker/u9:8/5864:
#0: ffff888025103148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888025103148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003027bc0 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003027bc0 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
1 lock held by udevd/6638:
#0: ffff88802510b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz.6.668/8391:
#0: ffff88802510b358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340 block/bdev.c:1288
1 lock held by syz-executor/8793:
#0: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller #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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
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: 8793 Comm: syz-executor Not tainted 6.16.0-rc6-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:kasan_check_range+0x1d3/0x2c0 mm/kasan/generic.c:189
Code: 4d 01 f3 49 8d 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 12 41 80 3b 00 0f 85 b8 00 00 00 49 ff c3 49 ff cc 75 ee <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 29 a4 ec fe cc 45 84 ff 75 63 41
RSP: 0018:ffffc9000be472f0 EFLAGS: 00000256
RAX: ffffffff8b6b6a01 RBX: 0000000000000000 RCX: ffffffff8b6b6aa6
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8b8b8920
RBP: ffffffff8b8b8921 R08: ffffffff8b8b8920 R09: 1ffffffff1717124
R10: dffffc0000000000 R11: fffffbfff1717125 R12: 0000000000000001
R13: ffffc9000be47620 R14: fffffbfff1717125 R15: 1ffffffff1717124
FS: 0000555579ae0500(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7f2a781ab8 CR3: 0000000042579000 CR4: 0000000000350ef0
Call Trace:
__asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
vsnprintf+0x386/0xf00 lib/vsprintf.c:2826
sprintf+0xd9/0x120 lib/vsprintf.c:3037
print_time kernel/printk/printk.c:1381 [inline]
info_print_prefix+0x155/0x310 kernel/printk/printk.c:1407
record_print_text+0x154/0x430 kernel/printk/printk.c:1456
printk_get_next_message+0x26d/0x7b0 kernel/printk/printk.c:3024
console_emit_next_record kernel/printk/printk.c:3092 [inline]
console_flush_all+0x4ca/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
bch2_print_maybe_redirect fs/bcachefs/super.c:137 [inline]
__bch2_print+0x176/0x220 fs/bcachefs/super.c:156
bch2_fs_free+0x526/0x5a0 fs/bcachefs/super.c:732
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
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:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f305838fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd85b72908 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3058410925 RCX: 00007f305838fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd85b729c0
RBP: 00007ffd85b729c0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd85b73a50
R13: 00007f3058410925 R14: 000000000005af3a R15: 00007ffd85b73a90