INFO: task syz.5.3905:23163 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3905 state:D stack:24360 pid:23163 tgid:23156 ppid:17386 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7536
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c4/0x15a0 kernel/locking/mutex.c:821
sync_bdevs+0x276/0x470 block/bdev.c:1369
ksys_sync fs/sync.c:105 [inline]
__ia32_sys_sync+0xc5/0x120 fs/sync.c:111
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6501b9e1d9
RSP: 002b:00007f64ffdd5028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f6501e26180 RCX: 00007f6501b9e1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6501e26180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6501e26218 R14: 00007f6501e26180 R15: 00007ffc5f8cd048
Showing all locks held in the system:
locks held by khungtaskd/33: 1, last CPU#1:
#0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8fd5a2a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by udevd/21672: 1, on CPU#1:
#0: ffff888028366350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:990
locks held by syz.5.3905/23163: 1, on CPU#1:
#0: ffff888028366350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x276/0x470 block/bdev.c:1369
locks held by getty/23919: 2, on CPU#0:
#0: ffff888033a240a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000588b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 33 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0x1073/0x10f0 kernel/hung_task.c:598
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 25786 Comm: dhcpcd-run-hook Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:open_last_lookups fs/namei.c:-1 [inline]
RIP: 0010:path_openat+0x3e2/0x1da0 fs/namei.c:5037
Code: 42 0f b6 04 28 84 c0 0f 85 59 07 00 00 83 cd 03 48 8b 04 24 89 28 e9 43 01 00 00 e8 e8 4e 75 ff 4c 8b 7c 24 20 e9 fa 00 00 00 <48> 8b 84 24 90 00 00 00 42 80 3c 28 00 74 08 48 89 df e8 b7 3d e8
RSP: 0018:ffffc90004ebfad8 EFLAGS: 00000202
RAX: ffffffff825348c3 RBX: ffffc90004ebfc38 RCX: 0000000000000000
RDX: ffff88807bc7be80 RSI: 0000000000000040 RDI: 0000000000000000
RBP: 0000000000030101 R08: ffff88807bc7be80 R09: 0000000000000002
R10: 0000000000002e2e R11: 0000000000000000 R12: 0000000000000040
R13: dffffc0000000000 R14: 0000000000008241 R15: ffffc90004ebfe00
FS: 00007fa9319e1c80(0000) GS:ffff888123aad000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa931c22943 CR3: 00000000612a8000 CR4: 00000000003526f0
Call Trace:
do_file_open+0x23e/0x4a0 fs/namei.c:5069
do_sys_openat2+0x115/0x200 fs/open.c:1442
do_sys_open fs/open.c:1448 [inline]
__do_sys_openat fs/open.c:1788 [inline]
__se_sys_openat fs/open.c:1783 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1783
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa931b31407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff44cc9780 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa9319e1c80 RCX: 00007fa931b31407
RDX: 0000000000000241 RSI: 000055c01c717070 RDI: ffffffffffffff9c
RBP: 000055c01c707c70 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055c01c709030
R13: 000055c01c717070 R14: 0000000000000001 R15: 0000000000000000