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INFO: rcu detected stall in io_wq_worker

Status: auto-obsoleted due to no activity on 2025/01/25 21:34
Subsystems: mm
[Documentation on labels]
First crash: 349d, last: 349d

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P32737/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=137881, q=580984 ncpus=2)
task:iou-wrk-32732   state:R  running task     stack:24664 pid:32737 tgid:32731 ppid:25090  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7012
 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:kasan_mem_to_shadow include/linux/kasan.h:61 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x3a/0x290 mm/kasan/generic.c:189
Code: f6 0f 84 a0 01 00 00 4c 8d 04 37 49 39 f8 0f 82 56 02 00 00 48 89 fd 48 c1 ed 2f 81 fd fe ff 01 00 0f 86 43 02 00 00 48 89 fb <48> c1 eb 03 49 ba 00 00 00 00 00 fc ff df 4e 8d 1c 13 49 ff c8 4d
RSP: 0018:ffffc9000d93f150 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff901d0328 RCX: ffffffff81706d70
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d0328
RBP: 000000000001ffff R08: ffffffff901d0330 R09: 1ffff1100390e91f
R10: dffffc0000000000 R11: ffffed100390e920 R12: 1ffff92001b27e3c
R13: ffffffff820b6797 R14: 1ffffd400018ba41 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:570 [inline]
 cpu_online include/linux/cpumask.h:1117 [inline]
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0xb0/0xa30 kernel/locking/lockdep.c:5836
 rcu_lock_release include/linux/rcupdate.h:347 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 page_ext_put+0xa3/0xc0 mm/page_ext.c:550
 page_table_check_free include/linux/page_table_check.h:41 [inline]
 free_pages_prepare mm/page_alloc.c:1109 [inline]
 free_unref_page+0xd0f/0xf20 mm/page_alloc.c:2638
 discard_slab mm/slub.c:2677 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3145
 put_cpu_partial+0x17c/0x250 mm/slub.c:3220
 __slab_free+0x2ea/0x3d0 mm/slub.c:4449
 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_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141
 alloc_empty_file+0x9e/0x1d0 fs/file_table.c:209
 path_openat+0x107/0x3590 fs/namei.c:3919
 do_filp_open+0x235/0x490 fs/namei.c:3960
 io_openat2+0x44e/0x690 io_uring/openclose.c:140
 io_issue_sqe+0x3cf/0x1570 io_uring/io_uring.c:1739
 io_wq_submit_work+0x7ba/0xbd0 io_uring/io_uring.c:1848
 io_worker_handle_work+0x85a/0x11c0 io_uring/io-wq.c:601
 io_wq_worker+0x4bc/0xed0 io_uring/io-wq.c:655
 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: rcu_preempt kthread starved for 6765 jiffies! g137881 f0x2 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:23568 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-rc4-syzkaller-00289-gea1fda89f5b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_acquire+0x72a/0x2050 kernel/locking/lockdep.c:5152
Code: 0f b6 cb 0f 44 c8 89 4c 24 54 48 8b 44 24 38 0f b6 04 10 84 c0 0f 85 74 13 00 00 41 8b 6d 00 41 89 ec ff cd 0f 88 a2 00 00 00 <89> eb 83 fd 31 73 79 48 8d 04 9b 48 8d 5c c6 20 48 89 d8 48 c1 e8
RSP: 0018:ffffc900001562d0 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: ffff88801ceb64e0 RDI: 0000000000000014
RBP: 0000000000000003 R08: ffffffff942ca8ef R09: 1ffffffff285951d
R10: dffffc0000000000 R11: fffffbfff285951e R12: 0000000000000004
R13: ffff88801ceb64d8 R14: 1ffff110039d6cb4 R15: ffff88801ceb65a0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005620e4bdfd88 CR3: 000000000e734000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 backlog_lock_irq_save net/core/dev.c:233 [inline]
 enqueue_to_backlog+0x17c/0xc80 net/core/dev.c:4874
 netif_rx_internal+0x17a/0x630 net/core/dev.c:5195
 __netif_rx+0x78/0xc0 net/core/dev.c:5215
 loopback_xmit+0x454/0x6b0 drivers/net/loopback.c:89
 __netdev_start_xmit include/linux/netdevice.h:4928 [inline]
 netdev_start_xmit include/linux/netdevice.h:4937 [inline]
 xmit_one net/core/dev.c:3588 [inline]
 dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3604
 __dev_queue_xmit+0x1b11/0x3ed0 net/core/dev.c:4428
 dev_queue_xmit include/linux/netdevice.h:3094 [inline]
 neigh_hh_output include/net/neighbour.h:526 [inline]
 neigh_output include/net/neighbour.h:540 [inline]
 ip6_finish_output2+0xfc9/0x1730 net/ipv6/ip6_output.c:141
 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:226
 synproxy_send_tcp_ipv6+0x568/0x7c0 net/netfilter/nf_synproxy_core.c:851
 synproxy_send_client_synack_ipv6+0x7d0/0xc30 net/netfilter/nf_synproxy_core.c:897
 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline]
 nft_synproxy_do_eval+0x739/0xa60 net/netfilter/nft_synproxy.c:145
 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
 nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288
 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5666 [inline]
 __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5779
 process_backlog+0x662/0x15b0 net/core/dev.c:6111
 __napi_poll+0xcb/0x490 net/core/dev.c:6775
 napi_poll net/core/dev.c:6844 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:6966
 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927
 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>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/27 21:24 upstream ea1fda89f5b2 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in io_wq_worker
* Struck through repros no longer work on HEAD.