INFO: rcu detected stall in ovs_dp_masks_rebalance (5)

Status: auto-obsoleted due to no activity on 2026/10/27 20:32
Subsystems: mm
Labels: prio:normal
[Documentation on labels]
First crash: 102d, last: 102d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
b1a55f37 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: rcu detected stall in ovs_dp_masks_rebalance (5) 2026/07/31 02:17 2026/07/31 02:17 2026/07/31 05:21 aaffb173
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ovs_dp_masks_rebalance mm 1 1 696d 696d 0/29 auto-obsoleted due to no activity on 2025/03/12 22:11
upstream INFO: rcu detected stall in ovs_dp_masks_rebalance (3) mm 1 2 453d 471d 0/29 auto-obsoleted due to no activity on 2025/11/11 01:29
upstream INFO: rcu detected stall in ovs_dp_masks_rebalance (2) mm 1 1 580d 580d 0/29 auto-obsoleted due to no activity on 2025/07/06 08:30
upstream INFO: rcu detected stall in ovs_dp_masks_rebalance (4) prio:high mm 1 10 230d 353d 0/29 auto-obsoleted due to no activity on 2026/06/21 23:58

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P22287/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=143505, q=2015 ncpus=2)
task:kworker/0:1     state:R  running task     stack:28088 pid:22287 tgid:22287 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events ovs_dp_masks_rebalance
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7234
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7556
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x205/0xa00 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 3b 75 7e 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 c6 47 3d 0f 0f 82 ac 02 00 00 8b 35 6e 7b 3d 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 74 7e 12 0f 85 ec 02 00 00 48 83 c4
RSP: 0018:ffffc9000f857950 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e182932 RDI: ffffffff8c400a80
RBP: ffffffff8ebe7f80 R08: 00000000711d834f R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:840 [inline]
 page_ext_get+0x36/0x1a0 mm/page_ext.c:531
 __reset_page_owner+0x2b/0x190 mm/page_owner.c:306
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4584 [inline]
 slab_alloc_node mm/slub.c:4917 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x2bf/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 ovs_flow_masks_rebalance+0xde/0xa00 net/openvswitch/flow_table.c:1112
 ovs_dp_masks_rebalance+0x64/0xf0 net/openvswitch/datapath.c:2597
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/29 20:25 upstream fc02acf6ac0c 2377cd3d .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in ovs_dp_masks_rebalance
* Struck through repros no longer work on HEAD.