rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=46e/1/0x4000000000000000 softirq=138858/138859 fqs=3 (t=10500 jiffies g=245393 q=139) rcu: rcu_preempt kthread starved for 10493 jiffies! g245393 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28872 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4322 [inline] __schedule+0x911/0x21b0 kernel/sched/core.c:5073 schedule+0xcf/0x270 kernel/sched/core.c:5152 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1892 rcu_gp_fqs_loop kernel/rcu/tree.c:2005 [inline] rcu_gp_kthread+0xd07/0x2250 kernel/rcu/tree.c:2178 kthread+0x3b1/0x4a0 kernel/kthread.c:292 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16199 Comm: syz-executor.2 Not tainted 5.12.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:queued_write_lock_slowpath+0x131/0x270 kernel/locking/qrwlock.c:76 Code: 00 00 00 00 fc ff df 49 01 c7 41 83 c6 03 41 0f b6 07 41 38 c6 7c 08 84 c0 0f 85 fe 00 00 00 8b 03 3d 00 01 00 00 74 19 f3 90 <41> 0f b6 07 41 38 c6 7c ec 84 c0 74 e8 48 89 df e8 8a 4b 5d 00 eb RSP: 0018:ffffc90017ef7970 EFLAGS: 00000206 RAX: 00000000000001ff RBX: ffffc90017b51000 RCX: ffffffff815a643a RDX: fffff52002f6a201 RSI: 0000000000000004 RDI: ffffc90017b51000 RBP: 00000000000000ff R08: 0000000000000001 R09: ffffc90017b51003 R10: fffff52002f6a200 R11: 0000000000000000 R12: 1ffff92002fdef2f R13: ffffc90017b51004 R14: 0000000000000003 R15: fffff52002f6a200 FS: 0000000001a67400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000540198 CR3: 00000000ad657000 CR4: 00000000001526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: queued_write_lock include/asm-generic/qrwlock.h:97 [inline] do_raw_write_lock+0x1ce/0x280 kernel/locking/spinlock_debug.c:207 kvm_mmu_notifier_invalidate_range_start+0x62/0x460 arch/x86/kvm/../../../virt/kvm/kvm_main.c:482 mn_hlist_invalidate_range_start mm/mmu_notifier.c:493 [inline] __mmu_notifier_invalidate_range_start+0x2ff/0x800 mm/mmu_notifier.c:548 mmu_notifier_invalidate_range_start include/linux/mmu_notifier.h:453 [inline] change_pmd_range mm/mprotect.c:247 [inline] change_pud_range mm/mprotect.c:297 [inline] change_p4d_range mm/mprotect.c:317 [inline] change_protection_range mm/mprotect.c:342 [inline] change_protection+0x1d48/0x20a0 mm/mprotect.c:365 mprotect_fixup+0x46c/0x940 mm/mprotect.c:487 do_mprotect_pkey+0x5c7/0xa50 mm/mprotect.c:626 __do_sys_mprotect mm/mprotect.c:652 [inline] __se_sys_mprotect mm/mprotect.c:649 [inline] __x64_sys_mprotect+0x74/0xb0 mm/mprotect.c:649 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466567 Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 00 00 00 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:0000000000a9fab8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 0000000000021000 RCX: 0000000000466567 RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f906c1a4000 RBP: 0000000000a9fb90 R08: 00000000ffffffff R09: 00007f906c1c3700 R10: 0000000000020022 R11: 0000000000000206 R12: 0000000000a9fca0 R13: 00007f906c1c3700 R14: 0000000000000000 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 16200 Comm: syz-executor.2 Not tainted 5.12.0-rc8-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+0x222/0x2a7 kernel/rcu/tree_stall.h:341 print_cpu_stall kernel/rcu/tree_stall.h:622 [inline] check_cpu_stall kernel/rcu/tree_stall.h:697 [inline] rcu_pending kernel/rcu/tree.c:3830 [inline] rcu_sched_clock_irq.cold+0x4f7/0x11dd kernel/rcu/tree.c:2650 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:1369 __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:632 RIP: 0010:trace_timer_expire_exit include/trace/events/timer.h:125 [inline] RIP: 0010:call_timer_fn+0x527/0x6b0 kernel/time/timer.c:1432 Code: fe e8 ed 91 10 00 45 84 ff 0f 84 8e fc ff ff e8 2f 8b 10 00 e8 19 db 9c ff e9 7f fc ff ff e8 20 8b 10 00 65 ff 05 89 85 9e 7e <48> 8b 05 c2 e3 4d 0c e8 ad d5 9f 07 31 ff 41 89 c4 89 c6 e8 b1 92 RSP: 0018:ffffc90000007d40 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000101 RCX: 0000000000000100 RDX: ffff888014fb9c40 RSI: ffffffff81636a30 RDI: 0000000000000003 RBP: ffffc90000007d78 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8163671a R11: 0000000000000000 R12: 0000000000000001 R13: 1ffff92000000fa9 R14: ffffffff87193ac0 R15: 0000000000000000 expire_timers kernel/time/timer.c:1476 [inline] __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1745 __run_timers kernel/time/timer.c:1726 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1758 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345 invoke_softirq kernel/softirq.c:221 [inline] __irq_exit_rcu kernel/softirq.c:422 [inline] irq_exit_rcu+0x134/0x200 kernel/softirq.c:434 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:632 RIP: 0010:mmu_page_add_parent_pte arch/x86/kvm/mmu/mmu.c:1624 [inline] RIP: 0010:link_shadow_page+0x102/0x200 arch/x86/kvm/mmu/mmu.c:2170 Code: 00 0f 0b e8 80 54 5b 00 48 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 eb 00 00 00 48 85 ed 4c 89 65 00 <74> 14 e8 57 54 5b 00 48 8d 53 58 48 89 ee 4c 89 f7 e8 b8 b9 ff ff RSP: 0018:ffffc9001793f7b0 EFLAGS: 00000286 RAX: dffffc0000000000 RBX: ffff88802b1ea9b0 RCX: ffffc9000d8dd000 RDX: 1ffff11014b7ec00 RSI: ffffffff8118a0d0 RDI: 0000000000000003 RBP: ffff8880a5bf6000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8118a09d R11: 0000000000000000 R12: 00100000a5b5a007 R13: 0000000000000000 R14: ffff8880939b8000 R15: 0000000000000000 __direct_map arch/x86/kvm/mmu/mmu.c:2898 [inline] direct_page_fault+0x1d04/0x2c90 arch/x86/kvm/mmu/mmu.c:3736 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:119 [inline] kvm_mmu_page_fault+0x180/0x1930 arch/x86/kvm/mmu/mmu.c:5021 handle_ept_violation+0x29c/0x6f0 arch/x86/kvm/vmx/vmx.c:5380 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6090 [inline] vmx_handle_exit+0x336/0x1900 arch/x86/kvm/vmx/vmx.c:6107 vcpu_enter_guest+0x23d6/0x47f0 arch/x86/kvm/x86.c:9231 vcpu_run arch/x86/kvm/x86.c:9297 [inline] kvm_arch_vcpu_ioctl_run+0x47d/0x19b0 arch/x86/kvm/x86.c:9525 kvm_vcpu_ioctl+0x467/0xd90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3316 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 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:00007f906c1e4188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 0000000000a9fb1f R14: 00007f906c1e4300 R15: 0000000000022000