INFO: task kworker/0:1:13 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D stack:23880 pid:   13 ppid:     2 flags:0x00004000
Workqueue: events_long flush_old_commits
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27
 reiserfs_sync_fs fs/reiserfs/super.c:76 [inline]
 flush_old_commits+0x1de/0x2f0 fs/reiserfs/super.c:111
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/0:1/13:
 #0: ffff888016871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90000d27d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff88807c3740e0 (&type->s_umount_key#51){.+.+}-{3:3}, at: flush_old_commits+0xc8/0x2f0 fs/reiserfs/super.c:97
 #3: ffff88801f0e7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3961:
 #0: ffff88802c2f4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
4 locks held by syz.0.15/5099:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7582 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0x5e/0xe0 kernel/kcov.c:329
Code: 41 54 53 48 8b 0c cd 80 d5 0e 8a 48 8b 54 24 20 65 4c 8b 05 c4 a6 8a 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 <65> 44 8b 1d b2 a6 8a 7e 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01
RSP: 0018:ffffc9000c8cf878 EFLAGS: 00000202
RAX: 000000000000001f RBX: 00007fff8197d0bc RCX: 0000000000000005
RDX: ffffffff88535a0d RSI: ffffffff8d2ecec0 RDI: 0000000000000080
RBP: ffffc9000c8cfb10 R08: ffff888021120000 R09: 000000000000001e
R10: 0000000000000034 R11: 0000000000000000 R12: 0000000000000080
R13: dffffc0000000000 R14: ffff88802a681800 R15: 00007fff8197d0c0
FS:  0000555559631500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff8197bed8 CR3: 0000000072009000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_ip_getsockopt net/ipv4/ip_sockglue.c:1548 [inline]
 ip_getsockopt+0x27d/0x1590 net/ipv4/ip_sockglue.c:1780
 tcp_getsockopt+0x1e3/0x2390 net/ipv4/tcp.c:4313
 __sys_getsockopt+0x1b0/0x230 net/socket.c:2247
 __do_sys_getsockopt net/socket.c:2262 [inline]
 __se_sys_getsockopt net/socket.c:2259 [inline]
 __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2259
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcbf1d2363a
Code: ff c3 66 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b8 0f 1f 44 00 00 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7
RSP: 002b:00007fff8197d098 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007fcbf1e7a2e0 RCX: 00007fcbf1d2363a
RDX: 0000000000000080 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007fff8197d0bc R09: 00007fff8197d4c7
R10: 00007fff8197d0c0 R11: 0000000000000246 R12: 00007fff8197d0c0
R13: 00007fff8197d0bc R14: 0000000000000000 R15: 0000000000000000
 </TASK>