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INFO: rcu detected stall in key_garbage_collector (3)

Status: auto-obsoleted due to no activity on 2026/05/02 01:09
Subsystems: mm
[Documentation on labels]
First crash: 196d, last: 122d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
c0996294-963f-4e2c-adc4-513fd94082e2 repro INFO: rcu detected stall in key_garbage_collector (3) 2026/03/08 01:11 2026/03/08 01:11 2026/03/08 01:21 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in key_garbage_collector mm kasan 1 1 679d 679d 0/29 auto-obsoleted due to no activity on 2024/10/21 15:53
upstream INFO: rcu detected stall in key_garbage_collector (2) mm 1 2 338d 344d 0/29 auto-obsoleted due to no activity on 2025/09/28 00:40

Sample crash report:
bridge0: received packet on veth0_to_bridge 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): P18107/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=111597, q=688 ncpus=2)
task:kworker/1:2     state:R  running task     stack:25328 pid:18107 tgid:18107 ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events key_garbage_collector
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7194
 irqentry_exit+0x17b/0x670 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x39/0x70 kernel/kcov.c:217
Code: 65 48 8b 15 a1 74 dd 11 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 e9 91 f4 72 09 8b 82 6c 16 00 00 85 c0 74 f1 <8b> 82 48 16 00 00 83 f8 02 75 e6 48 8b 8a 50 16 00 00 8b 92 4c 16
RSP: 0018:ffffc9001208f7d0 EFLAGS: 00000246
RAX: 0000000080000000 RBX: ffffea000103ba40 RCX: ffffffff827dd9b8
RDX: ffff88802af04980 RSI: ffffffff827dd4e0 RDI: ffffea000103ba40
RBP: ffffea000103ba40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffea000103ba40
R13: 000001114e21bee1 R14: 0000000000000000 R15: ffffea000103ba40
 lookup_page_ext+0x10/0x100 mm/page_ext.c:250
 page_ext_get+0x58/0x1a0 mm/page_ext.c:528
 __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:1433 [inline]
 __free_frozen_pages+0x822/0x1130 mm/page_alloc.c:2973
 discard_slab mm/slub.c:3346 [inline]
 __put_partials+0x127/0x160 mm/slub.c:3886
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:406
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 assoc_array_gc+0xed/0x15d0 lib/assoc_array.c:1472
 keyring_gc+0x1b5/0x2e0 security/keys/keyring.c:1743
 key_garbage_collector+0x7cd/0xa50 security/keys/gc.c:358
 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3421
 kthread+0x3b3/0x730 kernel/kthread.c:463
 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
net_ratelimit: 22641 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 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 (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/01 01:08 upstream ad9a728a3388 35764559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in key_garbage_collector
2025/11/19 12:08 upstream 8b690556d8fe 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in key_garbage_collector
2025/11/18 13:25 upstream e7c375b18160 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in key_garbage_collector
* Struck through repros no longer work on HEAD.