INFO: task hung in flush_to_ldisc
Status: upstream: reported C repro on 2019/12/06 09:35
First crash: 243d, last: 172d

Cause bisection: the bug happens on the oldest tested release
Crash: INFO: task hung in tty_ldisc_hangup (log)
Repro: C syz .config

Fix bisection: fixed by (bisect log):

commit e8c75a30a23c6ba63f4ef6895cbf41fd42f21aa2
Author: Jiri Slaby <>
Date: Fri Feb 28 11:54:06 2020 +0000

  vt: selection, push sel_lock up

similar bugs (3):
Kernel Title Repro Bisected Count Last Reported Patched Status
linux-4.19 INFO: task hung in flush_to_ldisc (2) 1 20d 20d 0/1 upstream: reported on 2020/07/14 17:44
linux-4.19 INFO: task hung in flush_to_ldisc 10 169d 232d 0/1 auto-closed as invalid on 2020/06/15 14:09
linux-4.14 INFO: task hung in flush_to_ldisc 8 162d 232d 0/1 auto-closed as invalid on 2020/06/23 11:01

Sample crash report:

Crashes (15):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro Maintainers
ci-upstream-kasan-gce-root 2019/12/15 19:14 upstream 07c4b9e9 eef6e580 .config log report syz C,,
ci-upstream-kasan-gce-smack-root 2020/02/14 07:39 upstream b19e8c68 5d7b90f1 .config log report,,
ci-upstream-kasan-gce-smack-root 2020/02/12 21:02 upstream f2850dd5 84f4fc8a .config log report,,
ci-upstream-kasan-gce-smack-root 2020/02/12 15:37 upstream 359c92c0 84f4fc8a .config log report,,
ci-upstream-kasan-gce-smack-root 2020/02/09 22:59 upstream d1ea35f4 35f5e45e .config log report,,
ci-upstream-kasan-gce-root 2020/01/29 09:06 upstream c677124e c8e81ce4 .config log report,,
ci-upstream-kasan-gce-root 2020/01/23 15:32 upstream 131701c6 3334d684 .config log report,,
ci-upstream-kasan-gce-root 2020/01/22 11:37 upstream d96d875e 8eda0b95 .config log report,,
ci-upstream-kasan-gce-selinux-root 2019/12/22 13:13 upstream b8e382a1 8b967267 .config log report,,
ci-upstream-kasan-gce-root 2019/12/18 09:46 upstream 2187f215 f2fe0772 .config log report,,
ci-upstream-kasan-gce-root 2019/12/16 17:39 upstream 510c9788 b80769fc .config log report,,
ci-upstream-kasan-gce-selinux-root 2019/12/16 02:43 upstream 07c4b9e9 eef6e580 .config log report,,
ci-upstream-kasan-gce-selinux-root 2019/12/13 20:47 upstream 37d4e84f 5b2ca5da .config log report,,
ci-upstream-kasan-gce-selinux-root 2019/12/05 03:36 upstream 63de3747 b2088328 .config log report,,
ci-upstream-linux-next-kasan-gce-root 2019/12/17 03:55 linux-next fca4fe89 d13d7958 .config log report,,