INFO: task hung in ip6gre_exit_batch_net

Status: auto-obsoleted due to no activity on 2024/09/16 15:09
Reported-by: syzbot+ad0624e64b8fc5e0745a@syzkaller.appspotmail.com
First crash: 828d, last: 811d
▶ ▼ Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in ip6gre_exit_batch_net (6) net 1 1 1142d 1142d 0/29 closed as invalid on 2023/09/07 14:36
upstream INFO: task hung in ip6gre_exit_batch_net (2) net 1 3 2475d 2476d 0/29 auto-closed as invalid on 2020/01/17 16:16
linux-5.15 INFO: task hung in ip6gre_exit_batch_net (2) origin:upstream 1 syz error 1 277d 277d 0/3 upstream: reported syz repro on 2025/11/24 02:32
linux-6.1 INFO: task hung in ip6gre_exit_batch_net (2) origin:lts-only 1 syz, C done 1 106d 106d 3/3 fixed on 2026/06/16 10:34
linux-4.19 INFO: task hung in ip6gre_exit_batch_net (2) 1 1 2090d 2090d 0/1 auto-closed as invalid on 2021/04/06 21:09
linux-4.19 INFO: task hung in ip6gre_exit_batch_net (3) 1 7 1688d 1855d 0/1 auto-closed as invalid on 2022/05/13 06:16
upstream INFO: task hung in ip6gre_exit_batch_net (4) net 1 syz unreliable 44 1743d 1794d 0/29 closed as invalid on 2021/12/14 20:12
upstream INFO: task hung in ip6gre_exit_batch_net net 1 6 2514d 3007d 0/29 closed as dup on 2018/06/04 15:23
linux-6.1 INFO: task hung in ip6gre_exit_batch_net 1 1 811d 811d 0/3 auto-obsoleted due to no activity on 2024/09/16 14:37
upstream INFO: task hung in ip6gre_exit_batch_net (5) net 1 1 1520d 1520d 0/29 auto-closed as invalid on 2022/09/28 06:40
linux-4.19 INFO: task hung in ip6gre_exit_batch_net 1 1 2492d 2492d 0/1 auto-closed as invalid on 2020/02/29 06:17
upstream INFO: task hung in ip6gre_exit_batch_net (3) net 1 18 1978d 2293d 0/29 auto-closed as invalid on 2021/06/27 10:57

Sample crash report:
INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted 5.15.160-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:21760 pid:    9 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 ip6gre_exit_batch_net+0xc0/0x460 net/ipv6/ip6_gre.c:1647
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:599

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/08 15:08 linux-5.15.y c61bd26ae81a 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in ip6gre_exit_batch_net
2024/05/25 21:10 linux-5.15.y c61bd26ae81a a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in ip6gre_exit_batch_net
2024/05/22 13:52 linux-5.15.y 83655231580b 4d098039 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in ip6gre_exit_batch_net
2024/05/22 11:04 linux-5.15.y 83655231580b 4d098039 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in ip6gre_exit_batch_net
* Struck through repros no longer work on HEAD.