INFO: task syz.1.1552:16364 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.1.1552 state:D stack:27640 pid:16364 tgid:16363 ppid:5810 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
bdev_open+0x41a/0xe40 block/bdev.c:961
blkdev_open+0x34e/0x4f0 block/fops.c:697
do_dentry_open+0x6d8/0x1660 fs/open.c:949
vfs_open+0x82/0x3f0 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x208c/0x31a0 fs/namei.c:4830
do_file_open+0x20e/0x430 fs/namei.c:4859
do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f95cbd5cfce
RSP: 002b:00007f95ccc82b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f95ccc836c0 RCX: 00007f95cbd5cfce
RDX: 0000000000000000 RSI: 00007f95ccc82c00 RDI: ffffffffffffff9c
RBP: 00007f95ccc82c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f95cc016038 R14: 00007f95cc015fa0 R15: 00007fff299ebad8
INFO: task syz.1.1552:16365 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1552 state:D stack:28792 pid:16365 tgid:16363 ppid:5810 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
bdev_open+0x41a/0xe40 block/bdev.c:961
blkdev_open+0x34e/0x4f0 block/fops.c:697
do_dentry_open+0x6d8/0x1660 fs/open.c:949
vfs_open+0x82/0x3f0 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x208c/0x31a0 fs/namei.c:4830
do_file_open+0x20e/0x430 fs/namei.c:4859
do_sys_openat2+0x10d/0x1e0 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x12d/0x210 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f95cbd5cfce
RSP: 002b:00007f95ccc61b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f95ccc626c0 RCX: 00007f95cbd5cfce
RDX: 0000000000022001 RSI: 00007f95ccc61c00 RDI: ffffffffffffff9c
RBP: 00007f95ccc61c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f95cc016128 R14: 00007f95cc016090 R15: 00007fff299ebad8
Showing all locks held in the system:
2 locks held by ksoftirqd/0/15:
#0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
#0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2c11/0x6120 kernel/sched/core.c:6902
1 lock held by khungtaskd/31:
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/0:2/55:
#0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
#0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2c11/0x6120 kernel/sched/core.c:6902
2 locks held by getty/5565:
#0: ffff888034b400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by udevd/5792:
#0: ffff888028453358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by udevd/5795:
#0: ffff888028456358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by syz.1.1552/16364:
#0: ffff888028456358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by syz.1.1552/16365:
#0: ffff888028456358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
2 locks held by syz.5.2019/19448:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:161 [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:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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: 5176 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:write_comp_data+0x2b/0x90 kernel/kcov.c:272
Code: 8b 05 59 04 05 12 49 89 f8 49 89 f1 49 89 d2 65 48 8b 3d 30 04 05 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 cc cc cc cc 8b 87 94 16 00 00 85 c0 74 f1 8b 87 70 16 00 00 83
RSP: 0018:ffffc900032777a8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffffff8c4c4c89 RCX: ffffffff8b8c25dd
RDX: 0000000000000043 RSI: 0000000000000009 RDI: ffff88807ace0000
RBP: ffffc90003277850 R08: 0000000000000005 R09: 0000000000000009
R10: 0000000000000043 R11: 0000000000000000 R12: 0000000000000073
R13: ffffc900032778e0 R14: ffffffff8c4c4c88 R15: 0000000000000043
FS: 00007fec5987b880(0000) GS:ffff888124445000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f99953e82f8 CR3: 0000000026c7c000 CR4: 00000000003526f0
Call Trace:
format_decode+0x2fd/0xcd0 lib/vsprintf.c:2712
vsnprintf+0x1c0/0x1240 lib/vsprintf.c:2890
add_uevent_var+0x183/0x3a0 lib/kobject_uevent.c:679
dev_uevent+0x133/0x8a0 drivers/base/core.c:2682
uevent_show+0x1ca/0x3a0 drivers/base/core.c:2756
dev_attr_show+0x52/0xa0 drivers/base/core.c:2421
sysfs_kf_seq_show+0x217/0x3a0 fs/sysfs/file.c:65
seq_read_iter+0x32f/0x1270 fs/seq_file.c:231
kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:297
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x825/0xb30 fs/read_write.c:574
ksys_read+0x12a/0x250 fs/read_write.c:717
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec590a7407
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:00007ffcd78d3440 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fec5987b880 RCX: 00007fec590a7407
RDX: 0000000000001000 RSI: 0000559490ec69c0 RDI: 000000000000000c
RBP: 00007fec591efff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007fec591efea0 R14: 0000000000000000 R15: 0000559490c706f0