rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10490 ticks this GP) idle=99a/1/0x4000000000000000 softirq=185131/185134 fqs=3 (t=10500 jiffies g=293261 q=81) rcu: rcu_preempt kthread starved for 10490 jiffies! g293261 f0x0 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:28800 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0x916/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1892 rcu_gp_fqs_loop kernel/rcu/tree.c:2004 [inline] rcu_gp_kthread+0xd07/0x2300 kernel/rcu/tree.c:2177 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15 Comm: migration/0 Not tainted 5.13.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Stopper: 0x0 <- 0x0 RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:434 [inline] RIP: 0010:__pv_queued_spin_lock_slowpath+0x3ba/0xb40 kernel/locking/qspinlock.c:508 Code: eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c f3 90 <41> 83 ec 01 0f 84 72 04 00 00 41 0f b6 45 00 38 d8 7f 08 84 c0 0f RSP: 0018:ffffc90000007a30 EFLAGS: 00000206 RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff19ac734 RDX: 0000000000000001 RSI: ffffffff817aec91 RDI: ffffffff8132b571 RBP: ffffffff8cd639a0 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817aec59 R11: 0000000000000080 R12: 0000000000001fda R13: fffffbfff19ac734 R14: 0000000000000001 R15: ffff8880b9c36400 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d523000 CR3: 0000000089af4000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:113 spin_lock include/linux/spinlock.h:354 [inline] mac80211_hwsim_tx_frame_no_nl.isra.0+0x68f/0x1330 drivers/net/wireless/mac80211_hwsim.c:1514 mac80211_hwsim_tx_frame+0x14f/0x1e0 drivers/net/wireless/mac80211_hwsim.c:1775 mac80211_hwsim_beacon_tx+0x4ba/0x910 drivers/net/wireless/mac80211_hwsim.c:1829 __iterate_interfaces+0x1e5/0x520 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x8d/0x170 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1852 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x609/0xe40 kernel/time/hrtimer.c:1601 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1618 __do_softirq+0x29b/0x9f6 kernel/softirq.c:559 invoke_softirq kernel/softirq.c:433 [inline] __irq_exit_rcu+0x136/0x200 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:647 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:199 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 ce 52 41 f8 48 89 ef e8 66 cb 41 f8 e8 c1 bf 61 f8 fb bf 01 00 00 00 46 c1 35 f8 65 8b 05 2f c3 e8 76 85 c0 74 02 5d c3 e8 eb 18 e7 RSP: 0018:ffffc90000d47d18 EFLAGS: 00000202 RAX: 0000000000000d1f RBX: 0000000000000000 RCX: 1ffffffff1b925e1 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001 RBP: ffff8880b9c35640 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817aec78 R11: 0000000000000001 R12: ffff8880b9c35640 R13: ffff888032401c40 R14: 0000000000000000 R15: ffff8880123d3880 finish_lock_switch kernel/sched/core.c:4093 [inline] finish_task_switch.isra.0+0x15d/0x810 kernel/sched/core.c:4210 context_switch kernel/sched/core.c:4342 [inline] __schedule+0x91e/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 smpboot_thread_fn+0x328/0x9e0 kernel/smpboot.c:161 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 NMI backtrace for cpu 1 CPU: 1 PID: 15827 Comm: syz-executor.4 Not tainted 5.13.0-rc3-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+0x141/0x1d7 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+0x25e/0x3f0 kernel/rcu/tree_stall.h:341 print_cpu_stall kernel/rcu/tree_stall.h:624 [inline] check_cpu_stall kernel/rcu/tree_stall.h:699 [inline] rcu_pending kernel/rcu/tree.c:3911 [inline] rcu_sched_clock_irq.cold+0x3f1/0x74b kernel/rcu/tree.c:2649 update_process_times+0x16d/0x200 kernel/time/timer.c:1796 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1373 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:647 RIP: 0010:mac80211_hwsim_tx_frame_no_nl.isra.0+0x72e/0x1330 drivers/net/wireless/mac80211_hwsim.c:1515 Code: 44 24 08 e8 74 86 4c fc 0f b6 44 24 08 84 c0 0f 85 a8 06 00 00 e8 b2 7f 4c fc e8 ad 7f 4c fc 48 89 d8 48 c1 e8 03 80 3c 28 00 <0f> 85 93 09 00 00 48 8b 1b 48 81 fb 60 39 d6 8c 0f 84 f7 04 00 00 RSP: 0018:ffffc90000dc0ba0 EFLAGS: 00000246 RAX: 1ffff1100e6a263c RBX: ffff8880735131e0 RCX: 0000000000000100 RDX: ffff88806916d4c0 RSI: ffffffff85285cd3 RDI: 0000000000000003 RBP: dffffc0000000000 R08: 0000000000000008 R09: 0000000000000000 R10: ffffffff85285d49 R11: 0000000000000000 R12: ffff888089cbd3c0 R13: ffff88807c393410 R14: ffff88807c3931e0 R15: 0000000000000000 mac80211_hwsim_tx_frame+0x14f/0x1e0 drivers/net/wireless/mac80211_hwsim.c:1775 mac80211_hwsim_beacon_tx+0x4ba/0x910 drivers/net/wireless/mac80211_hwsim.c:1829 __iterate_interfaces+0x1e5/0x520 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x8d/0x170 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1852 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x609/0xe40 kernel/time/hrtimer.c:1601 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1618 __do_softirq+0x29b/0x9f6 kernel/softirq.c:559 invoke_softirq kernel/softirq.c:433 [inline] __irq_exit_rcu+0x136/0x200 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:647 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:191 Code: 74 24 10 e8 8a 52 41 f8 48 89 ef e8 22 cb 41 f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 f3 c0 35 f8 65 8b 05 dc c2 e8 76 85 c0 74 0a 5b 5d c3 e8 50 bf RSP: 0018:ffffc9000237fa38 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff1b925e1 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001 RBP: ffff88802c810918 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817aec78 R11: 0000000000000000 R12: 0000000000000283 R13: ffff88802c810918 R14: ffff8880b9d35640 R15: ffff88802c810048 try_to_wake_up+0x618/0x14b0 kernel/sched/core.c:3485 wake_up_process kernel/sched/core.c:3552 [inline] wake_up_q+0x96/0x100 kernel/sched/core.c:597 futex_wake+0x3e9/0x490 kernel/futex.c:1634 do_futex+0x2a1/0x1750 kernel/futex.c:3737 __do_sys_futex kernel/futex.c:3805 [inline] __se_sys_futex kernel/futex.c:3786 [inline] __x64_sys_futex+0x1c6/0x4f0 kernel/futex.c:3786 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f584aee0218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 000000000056bf88 RCX: 00000000004665d9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000056bf8c RBP: 000000000056bf80 R08: 0000000000000016 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000056bf8c R13: 00007ffdcd73ec6f R14: 00007f584aee0300 R15: 0000000000022000