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INFO: rcu detected stall in sys_epoll_create1

Status: auto-obsoleted due to no activity on 2025/03/29 13:46
Subsystems: mm
[Documentation on labels]
First crash: 241d, last: 241d

Sample crash report:
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6544/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=11421, q=660 ncpus=2)
task:udevd           state:R  running task     stack:26752 pid:6544  tgid:6544  ppid:5203   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:page_ext_data include/linux/page_ext.h:86 [inline]
RIP: 0010:get_page_owner mm/page_owner.c:143 [inline]
RIP: 0010:__update_page_owner_free_handle mm/page_owner.c:269 [inline]
RIP: 0010:__reset_page_owner+0x136/0x430 mm/page_owner.c:298
Code: 1f 0f 87 a1 01 00 00 e8 78 47 90 ff 44 89 e7 8b 5c 24 24 89 de e8 2a 49 90 ff 44 39 e3 0f 84 a5 01 00 00 4c 8b 35 8a 8c 97 0c <4d> 01 fe 83 7c 24 0c 00 74 41 e8 4b 47 90 ff 4c 89 ff be 08 00 00
RSP: 0018:ffffc90019d87ba0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88805b27bc00
RDX: ffff88805b27bc00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff820f2c86 R09: 000000000000000c
R10: dffffc0000000000 R11: fffffbfff2032f87 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000008 R15: ffff88801d995640
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2657
 discard_slab mm/slub.c:2688 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3157
 put_cpu_partial+0x17c/0x250 mm/slub.c:3232
 __slab_free+0x290/0x380 mm/slub.c:4483
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 ep_alloc fs/eventpoll.c:1151 [inline]
 do_epoll_create+0x79/0x350 fs/eventpoll.c:2222
 __do_sys_epoll_create1 fs/eventpoll.c:2253 [inline]
 __se_sys_epoll_create1 fs/eventpoll.c:2251 [inline]
 __x64_sys_epoll_create1+0x37/0x40 fs/eventpoll.c:2251
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec9db23e27
RSP: 002b:00007ffcc59878d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000123
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fec9db23e27
RDX: 0000000000000008 RSI: 00007ffcc5987948 RDI: 0000000000080000
RBP: 0000558351e4c4c0 R08: 0000000000000007 R09: a0a618b1ec70e81f
R10: 0000000000080800 R11: 0000000000000206 R12: 0000558351e48df0
R13: 00007ffcc5987948 R14: 0000000000000000 R15: 0000558351e26910
 </TASK>
rcu: rcu_preempt kthread starved for 1932 jiffies! g11421 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:25976 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc3-syzkaller-00174-ga024e377efed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:clear_page_erms+0xb/0x20 arch/x86/lib/clear_page_64.S:50
Code: 48 8d 7f 40 75 d9 90 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa b9 00 10 00 00 31 c0 <f3> aa c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90
RSP: 0018:ffffc900001e6770 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000001000
RDX: ffff8880a1200000 RSI: 0000000000000001 RDI: ffff8880a1200000
RBP: 0000000000000004 R08: ffffea0002848037 R09: 0000000000000000
R10: ffffed1014240000 R11: fffff94000509007 R12: 0000000000000001
R13: 0000000000000001 R14: ffffea0002848000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b0a5d6abb8 CR3: 0000000060158000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 clear_page arch/x86/include/asm/page_64.h:54 [inline]
 clear_highpage_kasan_tagged include/linux/highmem.h:242 [inline]
 kernel_init_pages mm/page_alloc.c:1040 [inline]
 post_alloc_hook+0xf8/0x230 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
 alloc_slab_page+0x6a/0x110 mm/slub.c:2423
 allocate_slab+0x5a/0x2b0 mm/slub.c:2589
 new_slab mm/slub.c:2642 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830
 __slab_alloc+0x58/0xa0 mm/slub.c:3920
 __slab_alloc_node mm/slub.c:3995 [inline]
 slab_alloc_node mm/slub.c:4156 [inline]
 kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4175
 skb_clone+0x20c/0x390 net/core/skbuff.c:2084
 deliver_clone net/bridge/br_forward.c:125 [inline]
 br_flood+0x3dc/0x660 net/bridge/br_forward.c:245
 br_handle_frame_finish+0x18ba/0x1fe0 net/bridge/br_input.c:215
 br_nf_hook_thresh+0x472/0x590
 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0
 NF_HOOK include/linux/netfilter.h:314 [inline]
 br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:277 [inline]
 br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424
 __netif_receive_skb_core+0x14eb/0x4690 net/core/dev.c:5566
 __netif_receive_skb_one_core net/core/dev.c:5670 [inline]
 __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785
 process_backlog+0x662/0x15b0 net/core/dev.c:6117
 __napi_poll+0xcb/0x490 net/core/dev.c:6883
 napi_poll net/core/dev.c:6952 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7074
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
net_ratelimit: 23118 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:1b, 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:1b, 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: 27707 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:1b, 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:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/29 13:42 net a024e377efed d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_epoll_create1
* Struck through repros no longer work on HEAD.