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INFO: rcu detected stall in sys_epoll_create1 (2)

Status: auto-obsoleted due to no activity on 2025/08/29 18:50
Subsystems: mm
[Documentation on labels]
First crash: 131d, last: 131d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_epoll_create1 mm 1 1 284d 284d 0/29 auto-obsoleted due to no activity on 2025/03/29 13:46

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:ce:79:70:3a:0d:f5, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7814/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=20773, q=1897 ncpus=2)
task:syz.3.490       state:R  running task     stack:27136 pid:7814  tgid:7804  ppid:5834   task_flags:0x400040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7104
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x5/0x3e0 kernel/locking/lockdep.c:5879
Code: 03 48 8b 3c 24 e9 08 fa ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48 8b
RSP: 0018:ffffc9001a89f748 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff90405201 RCX: 12c556d74096b700
RDX: ffffc9001a89f801 RSI: ffffffff81724865 RDI: ffffffff8e13ccc0
RBP: dffffc0000000000 R08: ffffc9001a89fea0 R09: 0000000000000000
R10: ffffc9001a89f878 R11: fffff52003513f11 R12: ffffc9001a89feb0
R13: ffffc9001a898000 R14: ffffc9001a89f828 R15: ffffffff81724865
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1254 [inline]
 __free_frozen_pages+0xc6e/0xe50 mm/page_alloc.c:2717
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203
 alloc_empty_file+0x55/0x1d0 fs/file_table.c:234
 alloc_file fs/file_table.c:351 [inline]
 alloc_file_pseudo+0x13d/0x210 fs/file_table.c:380
 __anon_inode_getfile fs/anon_inodes.c:153 [inline]
 anon_inode_getfile+0xc5/0x1a0 fs/anon_inodes.c:191
 do_epoll_create+0x27b/0x340 fs/eventpoll.c:2251
 __do_sys_epoll_create1 fs/eventpoll.c:2270 [inline]
 __se_sys_epoll_create1 fs/eventpoll.c:2268 [inline]
 __x64_sys_epoll_create1+0x37/0x40 fs/eventpoll.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffb6c58e969
RSP: 002b:00007ffb6d345038 EFLAGS: 00000246 ORIG_RAX: 0000000000000123
RAX: ffffffffffffffda RBX: 00007ffb6c7b6160 RCX: 00007ffb6c58e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffb6c610ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ffb6c7b6160 R15: 00007ffc6024b0b8
 </TASK>
rcu: rcu_preempt kthread starved for 248 jiffies! g20773 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27128 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5392 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
 __schedule_loop kernel/sched/core.c:6859 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6874
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3403 Comm: kworker/R-bat_e Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bat_events batadv_tt_purge
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313
Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 e9 08 68 a6 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 a0 9b 92 65 8b 0d e8 a0
RSP: 0018:ffffc90000a07660 EFLAGS: 00000246
RAX: ffffffff8a197a23 RBX: 000000000000000d RCX: ffff888031011e00
RDX: 0000000000000100 RSI: 000000000000000d RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffc90000a079a0 R09: ffffc90000a079b0
R10: ffffc90000a07800 R11: fffff52000140f02 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff88802fe92cc8 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125d66000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8198ae56c0 CR3: 000000000df36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rt6_score_route+0x2c/0x380 net/ipv6/route.c:754
 find_match+0x1b0/0xc90 net/ipv6/route.c:786
 __find_rr_leaf+0x23a/0x6d0 net/ipv6/route.c:869
 find_rr_leaf net/ipv6/route.c:890 [inline]
 rt6_select net/ipv6/route.c:934 [inline]
 fib6_table_lookup+0x39f/0xa80 net/ipv6/route.c:2232
 ip6_pol_route+0x222/0x1180 net/ipv6/route.c:2268
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x52f/0x6f0 net/ipv6/fib6_rules.c:120
 ip6_route_input_lookup net/ipv6/route.c:2337 [inline]
 ip6_route_input+0x6ce/0xa50 net/ipv6/route.c:2640
 ip6_rcv_finish+0x141/0x2d0 net/ipv6/ip6_input.c:77
 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:993
 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:272 [inline]
 NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
 __netif_receive_skb_one_core net/core/dev.c:5977 [inline]
 __netif_receive_skb+0xd3/0x380 net/core/dev.c:6090
 netif_receive_skb_internal net/core/dev.c:6176 [inline]
 netif_receive_skb+0x1cb/0x790 net/core/dev.c:6235
 NF_HOOK+0x9d/0x390 include/linux/netfilter.h:318
 br_handle_frame_finish+0x14d1/0x19b0 net/bridge/br_input.c:-1
 br_nf_hook_thresh+0x3c3/0x4a0 net/bridge/br_netfilter_hooks.c:-1
 br_nf_pre_routing_finish_ipv6+0x948/0xd00 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:317 [inline]
 br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:283 [inline]
 br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:434
 __netif_receive_skb_core+0x10e1/0x4180 net/core/dev.c:5863
 __netif_receive_skb_one_core net/core/dev.c:5975 [inline]
 __netif_receive_skb+0x72/0x380 net/core/dev.c:6090
 process_backlog+0x60e/0x14f0 net/core/dev.c:6442
 __napi_poll+0xc7/0x480 net/core/dev.c:7414
 napi_poll net/core/dev.c:7478 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7605
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 do_softirq+0xec/0x180 kernel/softirq.c:480
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 batadv_tt_local_purge+0x2a7/0x340 net/batman-adv/translation-table.c:1315
 batadv_tt_purge+0x35/0x9e0 net/batman-adv/translation-table.c:3509
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 rescuer_thread+0x53c/0xdd0 kernel/workqueue.c:3498
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
net_ratelimit: 14109 callbacks suppressed
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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, vlan:0)
net_ratelimit: 16925 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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:ce:79:70:3a:0d:f5, 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
2025/05/31 18:49 net-next 90b83efa6701 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in sys_epoll_create1
* Struck through repros no longer work on HEAD.