INFO: task hung in tty_set_termios

Status: upstream: reported on 2026/10/27 23:39
Reported-by: syzbot+8cebba3a598b18ffbbc5@syzkaller.appspotmail.com
First crash: 1d16h, last: 1d16h
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in tty_set_termios (2) 1 3 1604d 1714d 0/1 auto-obsoleted due to no activity on 2022/10/05 22:41
upstream INFO: task hung in tty_set_termios (3) serial 1 1 1026d 1026d 0/29 auto-obsoleted due to no activity on 2024/04/06 00:03
upstream INFO: task hung in tty_set_termios serial 1 1 3135d 3133d 8/29 fixed on 2018/07/09 18:05
upstream INFO: task hung in tty_set_termios (4) serial 1 1 746d 746d 0/29 auto-obsoleted due to no activity on 2025/01/10 22:39
android-49 INFO: task hung in tty_set_termios 1 1 3048d 3048d 0/3 auto-closed as invalid on 2019/02/22 14:59
upstream INFO: task hung in tty_set_termios (5) serial 1 3 330d 396d 0/29 auto-obsoleted due to no activity on 2026/03/03 08:18
linux-4.19 INFO: task hung in tty_set_termios 1 1 2170d 2170d 0/1 auto-closed as invalid on 2021/03/18 18:50
upstream INFO: task hung in tty_set_termios (2) serial 1 2 1859d 1897d 0/29 auto-closed as invalid on 2021/12/25 14:45

Sample crash report:
INFO: task syz.3.4195:22257 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.4195      state:D stack:25328 pid:22257 ppid:15254  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 rwsem_down_write_slowpath+0xc99/0x1160 kernel/locking/rwsem.c:1189
 tty_set_termios+0x146/0x17e0 drivers/tty/tty_ioctl.c:355
 set_termios+0x4fe/0x680 drivers/tty/tty_ioctl.c:537
 tty_mode_ioctl+0x51e/0x6a0 drivers/tty/tty_ioctl.c:-1
 tty_ioctl+0x878/0xba0 drivers/tty/tty_io.c:2785
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2ed5b9f559
RSP: 002b:00007f2ed6aa2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2ed5e25fa0 RCX: 00007f2ed5b9f559
RDX: 0000200000000240 RSI: 00000000402c542b RDI: 0000000000000005
RBP: 00007f2ed5c36b20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2ed5e26038 R14: 00007f2ed5e25fa0 R15: 00007ffec71723b8
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/27 23:39 linux-6.1.y 79807e970724 96923c60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in tty_set_termios
* Struck through repros no longer work on HEAD.