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INFO: rcu detected stall in macvlan_process_broadcast (2)

Status: auto-obsoleted due to no activity on 2026/06/14 04:33
Subsystems: net
Labels: prio:normal
[Documentation on labels]
First crash: 102d, last: 102d
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
d95ef1d9-4984-4343-9f7a-9c7df0fd78ba assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ INFO: rcu detected stall in macvlan_process_broadcast (2) 2026/06/02 17:17 2026/06/02 17:17 2026/06/02 18:30 62fe15281f5011cd203d8845b8767b10e7443aa5

			
		
1636011d-879a-4670-be76-a7f500d01fc9 assessment-security 💥 INFO: rcu detected stall in macvlan_process_broadcast (2) 2026/05/26 02:36 2026/05/26 02:36 2026/05/26 03:54 c69befb30ac10e158cc9d1557b508ee3f0eca1de
agent reached max iterations limit (250)
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in macvlan_process_broadcast net 1 1 199d 199d 0/29 auto-obsoleted due to no activity on 2026/03/09 13:11

Sample crash report:
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10495/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=65745, q=863 ncpus=1)
task:kworker/u10:23  state:R  running task     stack:26888 pid:10495 tgid:10495 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound macvlan_process_broadcast
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7238
 irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:stack_access_ok+0xdf/0x1d0 arch/x86/kernel/unwind_orc.c:414
Code: c1 ea 03 80 3c 02 00 0f 85 dc 00 00 00 48 8b 73 28 48 89 da 48 89 ef e8 3f 6e f3 ff 85 c0 74 11 31 c0 48 83 c4 08 5b 5d 41 5c <41> 5d e9 9a dd d8 09 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1
RSP: 0018:ffffc90004ac7610 EFLAGS: 00000282
RAX: ffffc90004ac8001 RBX: 0000000000000001 RCX: ffffffff917731f4
RDX: ffffc90004ac7701 RSI: ffffc90004ac7778 RDI: ffffc90004ac76f0
RBP: ffffc90004ac7728 R08: ffffffff917731f8 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000000aeb9 R12: ffffc90004ac7730
R13: ffffc90004ac0000 R14: ffffc90004ac7780 R15: ffffc90004ac7714
 deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
 unwind_next_frame+0xb0b/0x1ea0 arch/x86/kernel/unwind_orc.c:600
 __unwind_start+0x3d1/0x7f0 arch/x86/kernel/unwind_orc.c:773
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x124/0x6a0 mm/slub.c:6295
 kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1151
 __kfree_skb net/core/skbuff.c:1218 [inline]
 consume_skb net/core/skbuff.c:1450 [inline]
 consume_skb+0xd1/0x110 net/core/skbuff.c:1444
 macvlan_process_broadcast+0x2b2/0x690 drivers/net/macvlan.c:345
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
net_ratelimit: 10036 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:f2:6e:bc:5b:30:bc, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:f2:6e:bc:5b:30:bc, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 10507 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:f2:6e:bc:5b:30:bc, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/16 04:27 upstream f338e7738378 ee8d34d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in macvlan_process_broadcast
* Struck through repros no longer work on HEAD.