rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=ecf/1/0x4000000000000000 softirq=53216/53216 fqs=33 (t=10500 jiffies g=84745 q=246) rcu: rcu_preempt kthread starved for 10421 jiffies! g84745 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:28952 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 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: 23686 Comm: syz-executor.3 Not tainted 5.15.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_is_held_type+0xe9/0x140 kernel/locking/lockdep.c:5670 Code: 83 e0 03 44 39 f0 41 0f 94 c5 48 c7 c7 c0 e6 8b 89 e8 bb 0d 00 00 b8 ff ff ff ff 65 0f c1 05 ee 96 cc 76 83 f8 01 75 29 9c 58 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 44 89 RSP: 0018:ffffc90000007d10 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 0000000000000004 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000010002 RDI: 0000000000000000 RBP: ffffffff8b97d3a0 R08: 0000000000000000 R09: ffff8880b9c32a8b R10: ffffed1017386551 R11: 0000000000000000 R12: ffff88807c5ac1c0 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88807c5acc30 FS: 00007fae7d2d6700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000001e1a2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x522/0x720 kernel/locking/lockdep.c:5636 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1681 [inline] __hrtimer_run_queues+0x51a/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:197 Code: fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 65 8b 05 f9 ba 8c 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 40 f0 01 00 a9 RSP: 0018:ffffc9001247f1f0 EFLAGS: 00000282 RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffffc9000fbd5000 RDX: 0000000000040000 RSI: ffffffff81ad9212 RDI: 0000000000000003 RBP: 0000000020001000 R08: 0000000020000000 R09: ffff88806b0670ff R10: ffffffff81ad9170 R11: 0000000000000000 R12: 0000000020001000 R13: ffff88801bf39108 R14: 0000000000000303 R15: 0000000000000000 __get_user_pages+0x1d8/0xf80 mm/gup.c:1125 __get_user_pages_locked mm/gup.c:1343 [inline] __gup_longterm_locked+0xb45/0xfb0 mm/gup.c:1793 get_user_pages+0x82/0xc0 mm/gup.c:1971 check_user_page_hwpoison arch/x86/kvm/../../../virt/kvm/kvm_main.c:2215 [inline] hva_to_pfn+0x9a0/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2407 __gfn_to_pfn_memslot+0x229/0x420 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2460 kvm_faultin_pfn+0x3d8/0xbc0 arch/x86/kvm/mmu/mmu.c:3957 direct_page_fault+0xd22/0x2320 arch/x86/kvm/mmu/mmu.c:3992 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:127 [inline] kvm_mmu_page_fault+0x17e/0x17f0 arch/x86/kvm/mmu/mmu.c:5287 handle_ept_violation+0x29c/0x6e0 arch/x86/kvm/vmx/vmx.c:5325 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6034 [inline] vmx_handle_exit+0x4be/0x1950 arch/x86/kvm/vmx/vmx.c:6051 vcpu_enter_guest+0x2a90/0x4410 arch/x86/kvm/x86.c:9735 vcpu_run arch/x86/kvm/x86.c:9802 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10034 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3779 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fae7fd5f8d9 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:00007fae7d2d6188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fae7fe63f60 RCX: 00007fae7fd5f8d9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007fae7fdb9cb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffde299b0af R14: 00007fae7d2d6300 R15: 0000000000022000 NMI backtrace for cpu 1 CPU: 1 PID: 23666 Comm: syz-executor.0 Not tainted 5.15.0-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:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 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:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:vcpu_enter_guest+0x28cf/0x4410 arch/x86/kvm/x86.c:9717 Code: 3c 02 00 0f 85 9a 17 00 00 48 b8 00 00 00 00 00 00 00 80 49 89 87 80 00 00 00 e8 bc eb 63 00 e8 c7 15 6a 00 fb bf 01 00 00 00 2c 6f 3d 00 31 ff 65 44 8b 3d a2 a6 f0 7e 44 89 fe e8 4a f4 63 RSP: 0018:ffffc900123cfb90 EFLAGS: 00000202 RAX: 00000000007c76c7 RBX: 1ffff92002479f7c RCX: 1ffffffff1fae8da RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffc900123cfcb0 R08: 0000000000000001 R09: ffffffff8fd02a4f R10: 0000000000000001 R11: 0000000000000001 R12: ffff888091c50bc0 R13: ffff888091c50bf8 R14: 0000000000000000 R15: 0000000000000000 vcpu_run arch/x86/kvm/x86.c:9802 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10034 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3779 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7ff8021d38d9 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:00007ff7ff74a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff8022d7f60 RCX: 00007ff8021d38d9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007ff80222dcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcff173b3f R14: 00007ff7ff74a300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess): 0: 83 e0 03 and $0x3,%eax 3: 44 39 f0 cmp %r14d,%eax 6: 41 0f 94 c5 sete %r13b a: 48 c7 c7 c0 e6 8b 89 mov $0xffffffff898be6c0,%rdi 11: e8 bb 0d 00 00 callq 0xdd1 16: b8 ff ff ff ff mov $0xffffffff,%eax 1b: 65 0f c1 05 ee 96 cc xadd %eax,%gs:0x76cc96ee(%rip) # 0x76cc9711 22: 76 23: 83 f8 01 cmp $0x1,%eax 26: 75 29 jne 0x51 28: 9c pushfq 29: 58 pop %rax * 2a: f6 c4 02 test $0x2,%ah <-- trapping instruction 2d: 75 3d jne 0x6c 2f: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 36: 00 37: 74 01 je 0x3a 39: fb sti 3a: 48 83 c4 08 add $0x8,%rsp 3e: 44 rex.R 3f: 89 .byte 0x89