INFO: task hung in cgroup_can_fork

Status: auto-obsoleted due to no activity on 2023/09/02 21:24
Subsystems: cgroups
[Documentation on labels]
Reported-by: syzbot+304cbc9725238275b855@syzkaller.appspotmail.com
First crash: 1683d, last: 1658d
Cause bisection: failed (error log, bisect log)
  
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] INFO: task hung in cgroup_can_fork 0 (1) 2021/12/22 22:13
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cgroup_can_fork (2) cgroups 1 5 675d 755d 0/29 auto-obsoleted due to no activity on 2024/12/20 05:36
linux-5.15 INFO: task hung in cgroup_can_fork (2) origin:upstream 1 syz, C error 59 13d 320d 0/3 upstream: reported C repro on 2025/09/11 03:23
linux-6.1 INFO: task hung in cgroup_can_fork 1 1 644d 644d 0/3 auto-obsoleted due to no activity on 2025/01/30 16:24
linux-6.1 INFO: task hung in cgroup_can_fork (2) origin:upstream 1 syz, C inconclusive 12 199d 308d 0/3 upstream: reported C repro on 2025/09/23 15:45
linux-5.15 INFO: task hung in cgroup_can_fork 1 1 661d 661d 0/3 auto-obsoleted due to no activity on 2025/01/13 02:23
▶ ▼ Last patch testing requests (5)
Created Duration User Patch Repo Result
2023/09/02 20:57 26m retest repro upstream OK log
2023/06/22 09:32 18m retest repro upstream report log
2023/04/12 23:11 19m retest repro upstream report log
2022/12/30 03:31 18m retest repro upstream report log
2022/09/20 19:29 14m retest repro upstream report log

Sample crash report:
INFO: task syz-executor812:3663 blocked for more than 165 seconds.
      Not tainted 5.16.0-rc5-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor812 state:D stack:27552 pid: 3663 ppid:  3654 flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 context_switch kernel/sched/core.c:4972 [inline] kernel/sched/core.c:6253
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326 kernel/sched/core.c:6326
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385 kernel/sched/core.c:6385
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock_common kernel/locking/mutex.c:680 [inline] kernel/locking/mutex.c:740
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 kernel/locking/mutex.c:740
 cgroup_css_set_fork kernel/cgroup/cgroup.c:6090 [inline]
 cgroup_css_set_fork kernel/cgroup/cgroup.c:6090 [inline] kernel/cgroup/cgroup.c:6206
 cgroup_can_fork+0x888/0xeb0 kernel/cgroup/cgroup.c:6206 kernel/cgroup/cgroup.c:6206
 copy_process+0x3636/0x75a0 kernel/fork.c:2292 kernel/fork.c:2292
 kernel_clone+0xe7/0xab0 kernel/fork.c:2582 kernel/fork.c:2582
 __do_sys_clone3+0x1ca/0x2e0 kernel/fork.c:2857 kernel/fork.c:2857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_x64 arch/x86/entry/common.c:50 [inline] arch/x86/entry/common.c:80
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fbc074509a9
RSP: 002b:00007fbc074022f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 0000000000000031 RCX: 00007fbc074509a9
RDX: 00007fbc074509a9 RSI: 0000000000000058 RDI: 0000000020000080
RBP: 00007fbc074d8408 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbc074d8400
R13: 00007fbc074d840c R14: 00007fbc074a6074 R15: 0000000280000000
 </TASK>
INFO: task syz-executor812:3664 blocked for more than 172 seconds.
      Not tainted 5.16.0-rc5-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor812 state:D stack:27552 pid: 3664 ppid:     1 flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 context_switch kernel/sched/core.c:4972 [inline] kernel/sched/core.c:6253
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326 kernel/sched/core.c:6326
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385 kernel/sched/core.c:6385
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock_common kernel/locking/mutex.c:680 [inline] kernel/locking/mutex.c:740
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 kernel/locking/mutex.c:740

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/18 22:02 upstream 9eaa88c7036e 44068e19 .config console log report syz C ci-upstream-kasan-gce INFO: task hung in cgroup_can_fork
2022/01/12 13:29 upstream daadb3bd0e8d 44d1319a .config console log report info ci-upstream-kasan-gce-root INFO: task hung in cgroup_can_fork
2021/12/22 10:16 upstream 2f47a9a4dfa3 6caa12e4 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in cgroup_can_fork
2021/12/22 09:58 upstream 2f47a9a4dfa3 6caa12e4 .config console log report info ci-upstream-kasan-gce-smack-root INFO: task hung in cgroup_can_fork
2021/12/19 22:51 upstream 3f667b5d4053 44068e19 .config console log report info ci-upstream-kasan-gce INFO: task hung in cgroup_can_fork
2021/12/18 14:21 upstream 9eaa88c7036e 44068e19 .config console log report info ci-upstream-kasan-gce INFO: task hung in cgroup_can_fork
* Struck through repros no longer work on HEAD.