rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (640 ticks this GP) idle=716c/1/0x4000000000000000 softirq=6726/6726 fqs=0 rcu: (t=10502 jiffies g=6113 q=402 ncpus=2) rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g6113 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=21560 rcu: rcu_preempt kthread starved for 10502 jiffies! g6113 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27904 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xedb/0x5af0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6778 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207 Code: fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 65 48 8b 14 25 c0 bc 03 00 <65> 8b 05 c4 2b 7c 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 RSP: 0018:ffffc90000007e10 EFLAGS: 00000046 RAX: 0000000000010203 RBX: ffff8880b982ba40 RCX: ffffffff81764017 RDX: ffff888016660000 RSI: ffff8880b982ba40 RDI: ffff8880284b7340 RBP: ffff8880284b7340 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: ffff8880b982b940 R13: 0000000000000000 R14: ffff8880284b7340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5b336df2d0 CR3: 000000000cd77000 CR4: 0000000000350ef0 Call Trace: debug_hrtimer_activate kernel/time/hrtimer.c:422 [inline] debug_activate kernel/time/hrtimer.c:477 [inline] enqueue_hrtimer+0x14/0x310 kernel/time/hrtimer.c:1087 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0xa12/0xc20 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:unwind_next_frame+0x15c/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: 95 4d 00 4d 85 e4 0f 85 d9 02 00 00 e8 6d 99 4d 00 4c 8d 7b 35 48 b8 00 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 0f b6 04 02 <4c> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 df 0b 00 00 48 b8 00 00 RSP: 0018:ffffc900000e76f0 EFLAGS: 00000213 RAX: 0000000000000000 RBX: ffffc900000e7770 RCX: 1ffffffff25010bc RDX: 1ffff9200001cef4 RSI: ffffffff8139f783 RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: 0000000000000000 R13: ffffffff8174f8a0 R14: ffffc900000e7830 R15: ffffc900000e77a5 arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 kvfree_call_rcu+0x70/0xbe0 kernel/rcu/tree.c:3400 neigh_destroy+0x435/0x670 net/core/neighbour.c:911 neigh_release include/net/neighbour.h:445 [inline] neigh_cleanup_and_release+0x1fe/0x290 net/core/neighbour.c:103 neigh_periodic_work+0x6a7/0xc40 net/core/neighbour.c:998 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.189 msecs CPU: 1 PID: 5136 Comm: kworker/1:3 Not tainted 6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:queued_write_lock_slowpath+0x179/0x330 kernel/locking/qrwlock.c:85 Code: 03 3d 00 01 00 00 74 37 48 b8 00 00 00 00 00 fc ff df 48 89 d9 48 89 da 48 c1 e9 03 83 e2 07 48 01 c1 83 c2 03 f3 90 0f b6 01 <38> c2 7c 08 84 c0 0f 85 5b 01 00 00 8b 03 3d 00 01 00 00 75 e6 48 RSP: 0018:ffffc900045ff560 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffffffff8ec890c0 RCX: fffffbfff1d91218 RDX: 0000000000000003 RSI: 0000000000000004 RDI: ffffffff8ec890c0 RBP: 1ffff920008bfeae R08: 0000000000000001 R09: fffffbfff1d91218 R10: ffffffff8ec890c3 R11: 0000000000000005 R12: ffffffff8ec890c4 R13: 0000000000000003 R14: fffffbfff1d91218 R15: ffffc900045ff5a0 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a99b6fb6d0 CR3: 000000007ecea000 CR4: 0000000000350ef0 Call Trace: queued_write_lock include/asm-generic/qrwlock.h:101 [inline] do_raw_write_lock+0x1d2/0x3b0 kernel/locking/spinlock_debug.c:210 ___neigh_create+0x9c2/0x2a20 net/core/neighbour.c:675 ip6_finish_output2+0x10e9/0x1830 net/ipv6/ip6_output.c:128 __ip6_finish_output net/ipv6/ip6_output.c:211 [inline] ip6_finish_output+0x3c7/0xf80 net/ipv6/ip6_output.c:222 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x1e2/0x530 net/ipv6/ip6_output.c:243 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xa13/0x18f0 net/ipv6/ndisc.c:509 ndisc_send_rs+0x133/0x6a0 net/ipv6/ndisc.c:719 addrconf_dad_completed+0x486/0x1030 net/ipv6/addrconf.c:4303 addrconf_dad_work+0x7f6/0x14b0 net/ipv6/addrconf.c:4211 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242