INFO: task syz.0.819:5214 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.819       state:D stack:27696 pid: 5214 ppid:  4974 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127
 _free_event+0x34/0xe30 kernel/events/core.c:5133
 put_event kernel/events/core.c:5258 [inline]
 perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5383
 perf_release+0x37/0x40 kernel/events/core.c:5393
 __fput+0x212/0x8c0 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc8e3c02f99
RSP: 002b:00007ffc56105db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007fc8e3e8afa0 RCX: 00007fc8e3c02f99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fc8e3c99ec4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8e3e8afac R14: 00007fc8e3e8afa0 R15: 00007fc8e3e8afa0
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3951:
 #0: ffff88814dac8098 (&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+0x594/0x1a50 drivers/tty/n_tty.c:2158

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 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+0xe1b/0xe60 kernel/hung_task.c:369
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3541 Comm: syslogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:__sanitizer_cov_trace_cmp8+0x7a/0x80 kernel/kcov.c:274
Code: c1 e0 05 4d 8d 50 28 4d 39 ca 77 1e 4a c7 44 02 08 06 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a <c3> 0f 1f 44 00 00 48 8b 04 24 65 48 8b 0d d4 6b 89 7e 65 8b 15 d5
RSP: 0018:ffffc90002dffa18 EFLAGS: 00000293
RAX: ffffffff889b214a RBX: 00000000000000ff RCX: ffff88807e033b80
RDX: 0000000000000000 RSI: 000000000000003d RDI: 00000000000000ff
RBP: ffffc90002dffb90 R08: ffffffff901ee177 R09: 1ffffffff203dc2e
R10: dffffc0000000000 R11: fffffbfff203dc2f R12: 1ffff920005bff50
R13: dffffc0000000000 R14: 000000000000003d R15: ffff88801f63a8c0
FS:  00007fe709ed5c80(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f60a229ee80 CR3: 000000002a6f3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __unix_dgram_recvmsg+0x62a/0xd50 net/unix/af_unix.c:2349
 sock_recvmsg_nosec net/socket.c:969 [inline]
 sock_recvmsg net/socket.c:987 [inline]
 sock_read_iter+0x2c2/0x380 net/socket.c:1068
 call_read_iter include/linux/fs.h:2167 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0x75e/0xd50 fs/read_write.c:485
 ksys_read+0x153/0x260 fs/read_write.c:623
 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: 0033:0x7fe70a025407
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:00007ffdcd10ddc0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fe709ed5c80 RCX: 00007fe70a025407
RDX: 00000000000000ff RSI: 00005594624ce950 RDI: 0000000000000000
RBP: 00005594624ce910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005594624ce9db
R13: 0000000000000000 R14: 00005594624ce950 R15: 0000559448e29d98
 </TASK>