syzbot


INFO: task hung in tty_release

Status: premoderation: reported on 2026/03/18 16:07
Reported-by: syzbot+8c5b201a1124b66f2d40@syzkaller.appspotmail.com
First crash: 11d, last: 11d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in tty_release serial 1 2 2814d 2814d 0/29 auto-closed as invalid on 2019/02/22 10:22
android-49 INFO: task hung in tty_release 1 21 2308d 2541d 0/3 auto-closed as invalid on 2020/04/02 02:37
linux-4.14 INFO: task hung in tty_release 1 1 2223d 2223d 0/1 auto-closed as invalid on 2020/06/26 02:50
upstream INFO: task hung in tty_release (2) serial 1 2 785d 842d 0/29 auto-obsoleted due to no activity on 2024/05/03 17:55

Sample crash report:
INFO: task syz.4.508:1975 blocked for more than 133 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.508       state:D stack:0     pid:1975  tgid:1975  ppid:1402   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8017
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 tty_lock+0x70/0xa0 drivers/tty/tty_mutex.c:18
 tty_release+0x80/0x1230 drivers/tty/tty_io.c:1736
 __fput+0x1fb/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e8/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x9e3/0x2650 kernel/exit.c:953
 do_group_exit+0x229/0x2f0 kernel/exit.c:1095
 get_signal+0x1398/0x14e0 kernel/signal.c:2933
 arch_do_signal_or_restart+0xbc/0x760 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 ret_from_fork+0x3a/0xa0 arch/x86/kernel/process.c:162
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
RIP: 0033:0x7f92ba39c799
RSP: 002b:00007f92bb173fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: 0000000000000000 RBX: 00007f92ba615fa0 RCX: 00007f92ba39c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f92ba432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92ba616038 R14: 00007f92ba615fa0 R15: 00007ffd066ff958
 </TASK>
INFO: task syz.1.597:2280 blocked for more than 139 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.597       state:D stack:0     pid:2280  tgid:2280  ppid:293    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/18 16:06 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in tty_release
* Struck through repros no longer work on HEAD.