INFO: task hung in udp_tunnel_nic_device_sync_work (2)

Status: closed as invalid on 2026/02/18 04:33
Subsystems: net
[Documentation on labels]
First crash: 292d, last: 292d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in udp_tunnel_nic_device_sync_work net 1 syz error 7 405d 432d 0/29 closed as invalid on 2025/09/10 00:16
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/01/04 02:19 18m retest repro upstream report log

Sample crash report:
INFO: task kworker/u4:5:119 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:5    state:D stack:19592 pid:119   tgid:119   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
 udp_tunnel_nic_device_sync_work+0x29/0xa10 net/ipv4/udp_tunnel_nic.c:736
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
INFO: task kworker/u4:13:1816 blocked for more than 153 seconds.

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/21 01:25 upstream d8ba32c5a460 d1b870e1 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root INFO: task hung in udp_tunnel_nic_device_sync_work
* Struck through repros no longer work on HEAD.