INFO: task hung in ovs_dp_masks_rebalance (8)

Status: upstream: reported on 2026/09/02 07:43
Subsystems: openvswitch
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+75ce0a9129024fa8cbf6@syzkaller.appspotmail.com
First crash: 406d, last: 6h20m
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
ab05d802 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: task hung in ovs_dp_masks_rebalance (8) 2026/05/15 14:10 2026/05/15 14:10 2026/05/15 16:16 efdaf0f9
140366a1 repro ❓ INFO: task hung in ovs_dp_masks_rebalance (8) 2026/03/07 14:03 2026/03/07 14:03 2026/03/07 14:13 31e9c887
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Title Replies (including bot) Last reply
[syzbot] [openvswitch?] INFO: task hung in ovs_dp_masks_rebalance (8) 0 (1) 2026/09/02 07:43
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in ovs_dp_masks_rebalance (7) openvswitch 1 5 581d 592d 0/29 auto-obsoleted due to no activity on 2025/04/28 19:38
upstream INFO: task hung in ovs_dp_masks_rebalance (3) openvswitch 1 1 1379d 1379d 0/29 auto-obsoleted due to no activity on 2023/04/22 10:20
upstream INFO: task hung in ovs_dp_masks_rebalance (2) openvswitch 1 68 1537d 1824d 0/29 auto-obsoleted due to no activity on 2022/10/15 22:59
upstream INFO: task hung in ovs_dp_masks_rebalance openvswitch 1 771 2189d 2232d 15/29 fixed on 2020/09/16 22:51
linux-6.1 INFO: task hung in ovs_dp_masks_rebalance 1 1 301d 301d 0/3 auto-obsoleted due to no activity on 2026/02/13 02:42
upstream INFO: task hung in ovs_dp_masks_rebalance (4) openvswitch 1 2 1146d 1166d 0/29 auto-obsoleted due to no activity on 2023/10/11 14:44
linux-6.1 INFO: task hung in ovs_dp_masks_rebalance (2) 1 4 63d 141d 0/3 upstream: reported on 2026/04/14 04:54
upstream INFO: task hung in ovs_dp_masks_rebalance (5) openvswitch 1 23 801d 833d 0/29 auto-obsoleted due to no activity on 2024/08/11 13:50
upstream INFO: task hung in ovs_dp_masks_rebalance (6) openvswitch 1 19 658d 712d 0/29 auto-obsoleted due to no activity on 2025/01/01 16:32

Sample crash report:
INFO: task kworker/0:0:9 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0     state:D stack:22128 pid:9     tgid:9     ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events ovs_dp_masks_rebalance
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7419
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821
 ovs_lock net/openvswitch/datapath.c:108 [inline]
 ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2602
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/u8:1:13 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:1    state:D stack:22376 pid:13    tgid:13    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7419
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821
 rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4770
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/u8:2:27 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:23808 pid:27    tgid:27    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7419
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821
 ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 ops_undo_list+0x28e/0x8d0 net/core/net_namespace.c:249
 cleanup_net+0x572/0x810 net/core/net_namespace.c:706
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task kworker/1:1:31 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1     state:D stack:22232 pid:31    tgid:31    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events ovs_dp_masks_rebalance
Call Trace:

Crashes (36):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/31 00:02 upstream a23cbb05744b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/30 16:38 upstream 08dbfad3f504 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/07/16 04:54 upstream 58717b2a1365 27a8bd60 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/07/12 07:28 upstream cab9e339cfbc d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/04/25 05:26 upstream 27d128c1cff6 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/04/08 00:40 upstream 3036cd0d3328 2c961e87 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in ovs_dp_masks_rebalance
2026/03/18 21:07 upstream a989fde763f4 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/02/22 20:51 upstream 32a92f8c8932 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/02/15 16:04 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in ovs_dp_masks_rebalance
2026/02/15 12:23 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in ovs_dp_masks_rebalance
2026/01/22 12:42 upstream a66191c590b3 2367ed1e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2025/12/28 19:00 upstream d26143bb38e2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2025/12/21 11:54 upstream 9094662f6707 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in ovs_dp_masks_rebalance
2025/12/20 03:50 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in ovs_dp_masks_rebalance
2025/09/16 02:03 upstream 46a51f4f5eda e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in ovs_dp_masks_rebalance
2025/07/23 05:06 upstream 89be9a83ccf1 e1dd4f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in ovs_dp_masks_rebalance
2026/06/20 21:53 upstream 1a3746ccbb0a 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in ovs_dp_masks_rebalance
2026/01/24 12:48 upstream c133687c2eae 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: task hung in ovs_dp_masks_rebalance
2026/08/30 21:17 net 2188569e7e1b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/30 08:33 net 2188569e7e1b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/10 00:03 net dd057113ac7b 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/04/21 23:59 net 478ed6b7d257 0b6ab7ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/09/02 01:58 net-next c8ea08ba34f2 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/29 09:11 net-next 1b78070aaef6 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/29 07:32 net-next 1b78070aaef6 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/28 10:30 net-next 1b78070aaef6 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/08/28 08:13 net-next 1b78070aaef6 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/07/01 14:01 net-next 1c664ec4b9ea 00a5cf1c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/06/28 01:44 net-next 805185b7c7a1 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/06/18 08:39 net-next b85966adbf5d b62b3ded .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/06/04 02:14 net-next a87533a80831 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/05/19 01:42 net-next 5a3a819389ad 9f74d399 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/05/12 20:47 net-next 73d587ae684d d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/05/09 16:51 net-next 8b2feced65cd 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2026/05/04 08:57 net-next 98878ed91b68 a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
2025/10/17 08:44 net-next 7e0d4c111369 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in ovs_dp_masks_rebalance
* Struck through repros no longer work on HEAD.