rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10421 ticks this GP) idle=c2a/1/0x4000000000000000 softirq=22609/22613 fqs=0 (t=10500 jiffies g=31125 q=323) rcu: rcu_preempt kthread starved for 10500 jiffies! g31125 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28752 pid: 13 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x148/0x250 kernel/time/timer.c:1878 rcu_gp_fqs_loop kernel/rcu/tree.c:1940 [inline] rcu_gp_kthread+0xbbe/0x1d70 kernel/rcu/tree.c:2113 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 NMI backtrace for cpu 1 CPU: 1 PID: 14441 Comm: syz-executor.0 Not tainted 5.11.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x1f4/0x230 kernel/rcu/tree_stall.h:337 print_cpu_stall kernel/rcu/tree_stall.h:569 [inline] check_cpu_stall kernel/rcu/tree_stall.h:643 [inline] rcu_pending kernel/rcu/tree.c:3751 [inline] rcu_sched_clock_irq.cold+0x48e/0xedf kernel/rcu/tree.c:2580 update_process_times+0x16d/0x200 kernel/time/timer.c:1782 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1369 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1102 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline] sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628 RIP: 0010:check_kcov_mode+0x1c/0x40 kernel/kcov.c:163 Code: fa c7 42 00 e9 18 fe ff ff cc cc cc cc cc 65 8b 05 89 36 8f 7e 89 c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 <8b> 96 cc 14 00 00 85 d2 74 0b 8b 86 a8 14 00 00 39 f8 0f 94 c0 c3 RSP: 0018:ffffc90000db0a30 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000100 RSI: ffff8880285b9bc0 RDI: 0000000000000003 RBP: ffff888029ca0bc0 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff884d0915 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff888054f58c80 R14: 1ffff920001b617f R15: ffff888013ff7f00 write_comp_data kernel/kcov.c:218 [inline] __sanitizer_cov_trace_const_cmp4+0x1c/0x70 kernel/kcov.c:284 __rhashtable_lookup+0x155/0x780 include/linux/rhashtable.h:594 rhltable_lookup include/linux/rhashtable.h:688 [inline] sta_info_hash_lookup net/mac80211/sta_info.c:162 [inline] sta_info_get_bss+0x144/0x3f0 net/mac80211/sta_info.c:199 __ieee80211_rx_handle_packet net/mac80211/rx.c:4625 [inline] ieee80211_rx_list+0x1057/0x2430 net/mac80211/rx.c:4746 ieee80211_rx_napi+0xf7/0x3d0 net/mac80211/rx.c:4769 ieee80211_rx include/net/mac80211.h:4508 [inline] ieee80211_tasklet_handler+0xd4/0x130 net/mac80211/main.c:235 tasklet_action_common.constprop.0+0x1d7/0x2d0 kernel/softirq.c:555 __do_softirq+0x2bc/0xa29 kernel/softirq.c:343 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:226 [inline] __irq_exit_rcu kernel/softirq.c:420 [inline] irq_exit_rcu+0x134/0x200 kernel/softirq.c:432 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628 RIP: 0010:lock_acquire+0x1d2/0x720 kernel/locking/lockdep.c:5410 Code: 48 c7 c7 a0 aa 4b 89 48 83 c4 20 e8 88 08 a1 07 b8 ff ff ff ff 65 0f c1 05 7b 3c a9 7e 83 f8 01 0f 85 da 03 00 00 ff 34 24 9d <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc90001a4fa18 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 1ffff92000349f45 RCX: 0000000000000001 RDX: 1ffff110050b74a8 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ed317b7 R10: fffffbfff1da62f6 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88805545c000 R14: 0000000000000000 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] task_lock include/linux/sched/task.h:166 [inline] mm_update_next_owner+0x21a/0x7a0 kernel/exit.c:413 exit_mm kernel/exit.c:500 [inline] do_exit+0xb62/0x2ae0 kernel/exit.c:812 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x427/0x20f0 kernel/signal.c:2773 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x46107a Code: Unable to access opcode bytes at RIP 0x461050. RSP: 002b:00007fd7df67ac48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e4 RAX: 0000000000000000 RBX: 00000000004d19e3 RCX: 000000000046107a RDX: 00000000005140e0 RSI: 00007fd7df67ac50 RDI: 0000000000000001 RBP: 000000000119bf80 R08: 0000000000000009 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffddb13081f R14: 00007fd7df67b9c0 R15: 000000000119bf8c