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INFO: rcu detected stall in listmount

Status: auto-obsoleted due to no activity on 2026/03/25 19:41
Subsystems: mm
[Documentation on labels]
First crash: 159d, last: 116d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
949ee827-8159-4828-a221-f0d705469a0c repro 💥 INFO: rcu detected stall in listmount 2026/03/10 12:27 2026/03/10 12:27 2026/03/10 12:28 5c03941b7fba0fd3b0326afc981322c89fe9ba52+ failed to run ["git" "revert" "--no-edit" "9362d34acf91a706c543d919ade3e651b9bd2d6f"]: exit status 128

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P27978/1:b..l P27986/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=199997, q=628 ncpus=1)
task:syz.7.4403      state:R  running task     stack:26120 pid:27986 tgid:27980 ppid:22468  task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: e9 cd 24 5d 00 be 03 00 00 00 5b e9 c2 18 ec 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 68 e7 f3 11 65 8b 05 79 e7 f3 11 a9 00 01 ff 00 74 1d
RSP: 0018:ffffc90003367558 EFLAGS: 00000283
RAX: 0000000000000002 RBX: ffff88801d602628 RCX: ffffffff8231cd03
RDX: ffff888032890000 RSI: ffffffff8231cd12 RDI: 0000000000000007
RBP: 000000000000000b R08: 0000000000000007 R09: 0000000000000010
R10: 000000000000000b R11: ffff888032890b30 R12: ffff88801d602600
R13: dffffc0000000000 R14: 00000000000002e0 R15: 000000000000000a
 sized_strscpy include/linux/fortify-string.h:329 [inline]
 __update_page_owner_handle+0x2e2/0x550 mm/page_owner.c:265
 __set_page_owner+0x126/0x560 mm/page_owner.c:342
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline]
 alloc_pages_noprof+0x131/0x390 mm/mempolicy.c:2577
 vm_area_alloc_pages mm/vmalloc.c:3649 [inline]
 __vmalloc_area_node mm/vmalloc.c:3863 [inline]
 __vmalloc_node_range_noprof+0xe6c/0x16b0 mm/vmalloc.c:4051
 __kvmalloc_node_noprof+0x42c/0xa40 mm/slub.c:7164
 kvmalloc_array_node_noprof include/linux/slab.h:1122 [inline]
 prepare_klistmount fs/namespace.c:5899 [inline]
 __do_sys_listmount+0x27f/0xf40 fs/namespace.c:5939
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4461d8f7c9
RSP: 002b:00007f4462cbf038 EFLAGS: 00000246 ORIG_RAX: 00000000000001ca
RAX: ffffffffffffffda RBX: 00007f4461fe6180 RCX: 00007f4461d8f7c9
RDX: 00000000000f4240 RSI: 0000000000000000 RDI: 0000200000000100
RBP: 00007f4461e13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4461fe6218 R14: 00007f4461fe6180 R15: 00007fff851bc6b8
 </TASK>
task:syz.6.4402      state:R  running task     stack:24568 pid:27978 tgid:27977 ppid:21355  task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 madvise_cold_or_pageout_pte_range+0x70e/0x2100 mm/madvise.c:560
 walk_pmd_range mm/pagewalk.c:130 [inline]
 walk_pud_range mm/pagewalk.c:224 [inline]
 walk_p4d_range mm/pagewalk.c:262 [inline]
 walk_pgd_range+0xc10/0x1f80 mm/pagewalk.c:303
 __walk_page_range+0x163/0x820 mm/pagewalk.c:410
 walk_page_range_vma_unsafe+0x23f/0x9e0 mm/pagewalk.c:714
 walk_page_range_vma+0x63/0x90 mm/pagewalk.c:724
 madvise_pageout_page_range mm/madvise.c:622 [inline]
 madvise_pageout+0x257/0x540 mm/madvise.c:647
 madvise_vma_behavior+0x912/0x29e0 mm/madvise.c:1366
 madvise_walk_vmas+0x31f/0xac0 mm/madvise.c:1721
 madvise_do_behavior+0x1e2/0x530 mm/madvise.c:1937
 do_madvise+0x176/0x240 mm/madvise.c:2030
 __do_sys_madvise mm/madvise.c:2039 [inline]
 __se_sys_madvise mm/madvise.c:2037 [inline]
 __x64_sys_madvise+0xa9/0x110 mm/madvise.c:2037
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa66b78f7c9
RSP: 002b:00007fa66c659038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fa66b9e5fa0 RCX: 00007fa66b78f7c9
RDX: 0000000000000015 RSI: ffffffffffff0001 RDI: 0000000000000000
RBP: 00007fa66b813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa66b9e6038 R14: 00007fa66b9e5fa0 R15: 00007fff2580b4d8
 </TASK>
rcu: rcu_preempt kthread starved for 751 jiffies! g199997 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27736 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Tainted: G     U       L      syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__nr_to_section+0x2/0xe0 include/linux/mmzone.h:1955
Code: b4 db f3 ff eb 9b 48 89 df e8 aa db f3 ff eb cd 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 54 <55> 53 48 89 fb 48 89 dd 48 c1 ed 07 e8 2d f9 8a ff e9 94 00 00 00
RSP: 0018:ffffc90000006ad8 EFLAGS: 00000203
RAX: 1ffffffff1bad8ac RBX: 00000000000859ff RCX: ffffffff8231ce05
RDX: dffffc0000000000 RSI: ffffffff823364e0 RDI: 0000000000000010
RBP: 00000000000859ff R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff88801d6e29b0 R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005588092f1088 CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __pfn_to_section include/linux/mmzone.h:2100 [inline]
 lookup_page_ext+0x46/0x100 mm/page_ext.c:251
 page_ext_iter_begin include/linux/page_ext.h:132 [inline]
 __update_page_owner_handle+0xd9/0x550 mm/page_owner.c:256
 __set_page_owner+0x126/0x560 mm/page_owner.c:342
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab mm/slub.c:3248 [inline]
 new_slab+0x2c3/0x430 mm/slub.c:3302
 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656
 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779
 __slab_alloc_node mm/slub.c:4855 [inline]
 slab_alloc_node mm/slub.c:5251 [inline]
 kmem_cache_alloc_node_noprof+0x44a/0x800 mm/slub.c:5315
 __alloc_skb+0x156/0x410 net/core/skbuff.c:679
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nlmsg_new include/net/netlink.h:1055 [inline]
 fdb_notify+0xa4/0x1a0 net/bridge/br_fdb.c:188
 br_fdb_update+0x323/0x7c0 net/bridge/br_fdb.c:1036
 br_handle_frame_finish+0xdf1/0x1f00 net/bridge/br_input.c:144
 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1167
 br_nf_pre_routing_finish_ipv6+0x76a/0xfc0 net/bridge/br_netfilter_ipv6.c:154
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184
 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0xb28/0x14e0 net/bridge/br_input.c:442
 __netif_receive_skb_core.constprop.0+0x6b3/0x35b0 net/core/dev.c:6024
 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6135
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 process_backlog+0x4a2/0x1650 net/core/dev.c:6602
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 do_softirq kernel/softirq.c:523 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:510
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 neigh_periodic_work+0x6da/0xc10 net/core/neighbour.c:1039
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
net_ratelimit: 6306 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, vlan:0)
net_ratelimit: 6454 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, 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 veth0_to_bridge with own address as source address (addr:96:b0:e1:bc:32:cb, vlan:0)

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/25 19:35 upstream ccd1cdca5cd4 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in listmount
2025/11/13 02:52 upstream 24172e0d7990 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in listmount
* Struck through repros no longer work on HEAD.