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INFO: task hung in commit_echoes (7)

Status: auto-obsoleted due to no activity on 2026/01/24 16:28
Subsystems: serial
[Documentation on labels]
First crash: 107d, last: 107d
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in commit_echoes serial 1 1 2782d 2778d 8/29 fixed on 2018/07/09 18:05
android-49 INFO: task hung in commit_echoes 1 C 44 2775d 2497d 0/3 public: reported C repro on 2019/04/11 08:44
upstream INFO: task hung in commit_echoes (6) serial 1 1 263d 263d 0/29 auto-obsoleted due to no activity on 2025/08/21 17:16
upstream INFO: task hung in commit_echoes (2) serial 1 3 1965d 2002d 0/29 auto-closed as invalid on 2020/12/23 20:14
upstream INFO: task hung in commit_echoes (4) serial 1 1 998d 998d 0/29 auto-obsoleted due to no activity on 2023/07/19 08:09
upstream INFO: task hung in commit_echoes (5) serial 1 2 372d 385d 0/29 auto-obsoleted due to no activity on 2025/05/04 22:28
linux-4.19 INFO: task hung in commit_echoes 1 1 2234d 2234d 0/1 auto-closed as invalid on 2020/04/28 11:37
upstream INFO: task hung in commit_echoes (3) serial 1 3 1285d 1380d 0/29 auto-obsoleted due to no activity on 2022/11/03 18:56

Sample crash report:
INFO: task syz.4.1662:13255 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1662      state:D stack:28744 pid:13255 tgid:13250 ppid:5817   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
 commit_echoes+0x4c/0x210 drivers/tty/n_tty.c:740
 n_tty_receive_char+0x3d7/0x600 drivers/tty/n_tty.c:1421
 n_tty_receive_buf_standard+0x6aa/0x3140 drivers/tty/n_tty.c:1590
 __receive_buf drivers/tty/n_tty.c:1624 [inline]
 n_tty_receive_buf_common+0x8eb/0x1980 drivers/tty/n_tty.c:1723

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/26 16:28 upstream 72761a7e3122 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in commit_echoes
* Struck through repros no longer work on HEAD.