INFO: task hung in ip_tunnel_delete_nets

Status: upstream: reported on 2026/06/07 20:57
Reported-by: syzbot+ac95389c06ff9d8eb474@syzkaller.appspotmail.com
First crash: 49d, last: 49d
▶ ▼ Similar bugs (12)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in ip_tunnel_delete_nets 1 1 1179d 1179d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:02
linux-6.1 INFO: task hung in ip_tunnel_delete_nets (2) 1 9 732d 795d 0/3 auto-obsoleted due to no activity on 2024/11/01 23:50
upstream INFO: task hung in ip_tunnel_delete_nets (3) net 1 1 2147d 2147d 0/29 auto-closed as invalid on 2020/12/07 06:22
linux-4.19 INFO: task hung in ip_tunnel_delete_nets 1 1 1700d 1700d 0/1 auto-closed as invalid on 2022/03/29 13:03
upstream INFO: task hung in ip_tunnel_delete_nets (2) net 1 2 2260d 2272d 0/29 auto-closed as invalid on 2020/08/16 16:51
upstream INFO: task hung in ip_tunnel_delete_nets net 1 2 2476d 2480d 0/29 closed as invalid on 2019/10/23 07:54
upstream INFO: task hung in ip_tunnel_delete_nets (6) net 1 2 888d 928d 0/29 auto-obsoleted due to no activity on 2024/05/19 21:58
upstream INFO: task hung in ip_tunnel_delete_nets (4) net 1 2 1489d 1489d 0/29 auto-closed as invalid on 2022/09/26 14:02
linux-4.19 INFO: task hung in ip_tunnel_delete_nets (2) 1 1 1315d 1315d 0/1 auto-obsoleted due to no activity on 2023/04/18 11:45
linux-6.1 INFO: task hung in ip_tunnel_delete_nets (3) 1 1 214d 214d 0/3 auto-obsoleted due to no activity on 2026/04/04 00:00
linux-6.1 INFO: task hung in ip_tunnel_delete_nets (4) 1 1 60d 60d 0/3 upstream: reported on 2026/05/27 21:28
upstream INFO: task hung in ip_tunnel_delete_nets (5) net 1 15 1053d 1358d 0/29 auto-obsoleted due to no activity on 2023/12/06 23:00

Sample crash report:
INFO: task kworker/u4:8:3458 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:8    state:D stack:21736 pid:3458  ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747
 ip_tunnel_delete_nets+0xd4/0x370 net/ipv4/ip_tunnel.c:1152

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/07 20:57 linux-6.6.y 924b4a879cbb cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: task hung in ip_tunnel_delete_nets
* Struck through repros no longer work on HEAD.