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INFO: rcu detected stall in evict

Status: auto-obsoleted due to no activity on 2026/03/24 09:25
Subsystems: fs
[Documentation on labels]
First crash: 114d, last: 114d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
cdb6d7d7-dc6a-4860-9b37-40f384e736a8 repro INFO: rcu detected stall in evict 2026/03/08 01:41 2026/03/08 01:41 2026/03/08 01:51 31e9c887f7dc24e04b3ca70d0d54fc34141844b0

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6177/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=30473, q=2171 ncpus=1)
task:kworker/u8:19   state:R  running task     stack:22328 pid:6177  tgid:6177  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: krdsd rds_shutdown_worker
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:orc_ip arch/x86/kernel/unwind_orc.c:81 [inline]
RIP: 0010:__orc_find+0x7e/0xf0 arch/x86/kernel/unwind_orc.c:103
Code: ea 3f 48 c1 fe 02 48 01 f2 48 d1 fa 48 8d 5c 95 00 48 89 da 48 c1 ea 03 0f b6 34 0a 48 89 da 83 e2 07 83 c2 03 40 38 f2 7c 05 <40> 84 f6 75 4b 48 63 13 48 01 da 49 39 d5 73 af 4c 8d 63 fc 49 39
RSP: 0018:ffffc90004ff74a8 EFLAGS: 00000202
RAX: ffffffff9132129c RBX: ffffffff90a93bf4 RCX: dffffc0000000000
RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffffffff90a93bf4
RBP: ffffffff90a93bf4 R08: ffffffff913212d2 R09: 000000006092a7b8
R10: 0000000000000002 R11: 00000000000142da R12: ffffffff90a93bf4
R13: ffffffff8242da68 R14: ffffffff90a93bf4 R15: ffffffff90a93bf4
 orc_find arch/x86/kernel/unwind_orc.c:238 [inline]
 unwind_next_frame+0x2ec/0x20b0 arch/x86/kernel/unwind_orc.c:510
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
 __call_rcu_common.constprop.0+0xa5/0xa10 kernel/rcu/tree.c:3119
 destroy_inode+0x12c/0x1b0 fs/inode.c:401
 evict+0x599/0xad0 fs/inode.c:861
 iput_final fs/inode.c:1951 [inline]
 iput.part.0+0x621/0x1190 fs/inode.c:2003
 iput+0x35/0x40 fs/inode.c:1966
 __sock_release net/socket.c:674 [inline]
 sock_release+0x17c/0x1d0 net/socket.c:690
 rds_tcp_conn_path_shutdown+0x1f9/0x410 net/rds/tcp_connect.c:220
 rds_conn_shutdown+0x28b/0xaa0 net/rds/connection.c:399
 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>
rcu: rcu_preempt kthread starved for 655 jiffies! g30473 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:28440 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: 5899 Comm: kworker/0:5 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
RIP: 0010:in_softirq_really kernel/kcov.c:171 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data+0x24/0x90 kernel/kcov.c:246
Code: 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 87 ee f3 11 65 8b 05 98 ee f3 11 a9 00 01 ff 00 74 1d f6 c4 01 74 67 <a9> 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 6c 16 00 00 85 c0
RSP: 0018:ffffc900000068e0 EFLAGS: 00000202
RAX: 0000000080000101 RBX: 0000000000000003 RCX: ffffffff8a1e1a31
RDX: ffff88802fdb0000 RSI: 00000000ffffffff RDI: 0000000000000005
RBP: ffffc900000069f0 R08: 0000000000000005 R09: 00000000ffffffff
R10: 00000000fffffffd R11: ffff88802fdb0b30 R12: 00000000fffffffd
R13: ffff88805db228c8 R14: 1ffff92000000d2c R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555568e8a5c8 CR3: 000000000e184000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 find_match+0x231/0x15d0 net/ipv6/route.c:786
 __find_rr_leaf+0x140/0xe00 net/ipv6/route.c:868
 find_rr_leaf net/ipv6/route.c:889 [inline]
 rt6_select net/ipv6/route.c:933 [inline]
 fib6_table_lookup+0x57c/0xa30 net/ipv6/route.c:2233
 ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2269
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:120
 ip6_route_input_lookup net/ipv6/route.c:2338 [inline]
 ip6_route_input+0x662/0xc70 net/ipv6/route.c:2641
 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66
 ip6_rcv_finish+0x130/0x580 net/ipv6/ip6_input.c:77
 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:990
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
 nf_hook.constprop.0+0x424/0x750 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 ipv6_rcv+0xa4/0x650 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6137
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 netif_receive_skb_internal net/core/dev.c:6336 [inline]
 netif_receive_skb+0x137/0x760 net/core/dev.c:6395
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70
 br_handle_frame_finish+0x10e8/0x1f00 net/bridge/br_input.c:235
 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
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline]
 kernel_fpu_end arch/x86/kernel/fpu/core.c:480 [inline]
 kernel_fpu_end+0x5e/0x70 arch/x86/kernel/fpu/core.c:473
 blake2s_compress+0x77/0xe0 lib/crypto/x86/blake2s.h:42
 blake2s_update+0xef/0x300 lib/crypto/blake2s.c:119
 hmac.constprop.0+0x23f/0x420 drivers/net/wireguard/noise.c:324
 kdf.constprop.0+0x122/0x280 drivers/net/wireguard/noise.c:360
 mix_dh+0xd2/0x130 drivers/net/wireguard/noise.c:413
 wg_noise_handshake_create_response+0x36f/0x5f0 drivers/net/wireguard/noise.c:702
 wg_packet_send_handshake_response+0xe0/0x310 drivers/net/wireguard/send.c:94
 wg_receive_handshake_packet+0x247/0xbf0 drivers/net/wireguard/receive.c:154
 wg_packet_handshake_receive_worker+0x16d/0x380 drivers/net/wireguard/receive.c:213
 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: 10720 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:3a:b7:1d:e4:b5:81, vlan:0)
net_ratelimit: 7580 callbacks suppressed
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:3a:b7:1d:e4:b5:81, 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:3a:b7:1d:e4:b5:81, 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:3a:b7:1d:e4:b5:81, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/24 09:18 upstream b927546677c8 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in evict
* Struck through repros no longer work on HEAD.