rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=491469, q=2122 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 8370 (4295176706-4295168336), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 8370 jiffies! g491469 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:25232 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 5272 Comm: syz-executor Not tainted 6.10.0-rc6-syzkaller-00069-g795c58e4c7fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:queued_write_lock_slowpath+0x164/0x44a kernel/locking/qrwlock.c:85 Code: 41 81 0f 00 01 00 00 48 8b 5c 24 08 43 0f b6 04 2e 84 c0 0f 85 94 00 00 00 41 8b 07 3d 00 01 00 00 74 27 f3 90 43 0f b6 04 2e <84> c0 74 eb 44 89 f9 80 e1 07 80 c1 03 38 c1 7c de 4c 89 ff e8 73 RSP: 0000:ffffc900000074c0 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 1ffff92000000ea2 RCX: ffffffff8b90f6c9 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8f6f9980 RBP: ffffc90000007570 R08: ffffffff8f6f9983 R09: 1ffffffff1edf330 R10: dffffc0000000000 R11: fffffbfff1edf331 R12: ffffc90000007510 R13: dffffc0000000000 R14: 1ffffffff1edf330 R15: ffffffff8f6f9980 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f0f022bc CR3: 000000006d9e2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: queued_write_lock include/asm-generic/qrwlock.h:101 [inline] do_raw_write_lock+0x395/0x4f0 kernel/locking/spinlock_debug.c:211 ___neigh_create+0xe7e/0x2470 net/core/neighbour.c:682 ip6_finish_output2+0x1629/0x1670 net/ipv6/ip6_output.c:128 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509 addrconf_rs_timer+0x36e/0x660 net/ipv6/addrconf.c:4039 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:write_comp_data kernel/kcov.c:236 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0xa4/0x120 kernel/kcov.c:341 Code: 8b 00 00 00 4c 8b 4c 24 20 65 4c 8b 1c 25 c0 d4 03 00 31 d2 eb 08 48 ff c2 49 39 d2 74 71 4c 8b 74 d6 10 65 8b 05 54 a7 6d 7e 00 01 ff 00 74 11 a9 00 01 00 00 74 de 41 83 bb 1c 16 00 00 00 RSP: 0000:ffffc9000350f400 EFLAGS: 00000206 RAX: 0000000080000001 RBX: 0000000000000000 RCX: ffff888069dd5a00 RDX: 0000000000000002 RSI: ffffffff8e1a1380 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000005 R09: ffffffff8140f7ae R10: 0000000000000008 R11: ffff888069dd5a00 R12: ffffffff90265dc4 R13: dffffc0000000000 R14: 0000000000000004 R15: 1ffff920006a1ea0 unwind_next_frame+0x7be/0x2a00 arch/x86/kernel/unwind_orc.c:515 arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x75/0x3f0 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2588 vfree+0x186/0x2e0 mm/vmalloc.c:3355 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x24a/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa27/0x27e0 kernel/exit.c:874 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7432579 Code: Unable to access opcode bytes at 0xf743254f. RSP: 002b:00000000f7584640 EFLAGS: 00000206 ORIG_RAX: 0000000000000066 RAX: 0000000000000000 RBX: 000000000000000f RCX: 00000000f7584678 RDX: 00000000f75846f4 RSI: 00000000f758474c RDI: 00000000f741dff4 RBP: 00000000f74237f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000