rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=ad3/1/0x4000000000000000 softirq=18589/18590 fqs=14 (t=10500 jiffies g=27273 q=272) rcu: rcu_preempt kthread starved for 10469 jiffies! g27273 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:28616 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4910 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 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+0x405/0x4f0 kernel/kthread.c:327 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: 11153 Comm: syz-executor.2 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_object_activate+0x269/0x3e0 lib/debugobjects.c:667 Code: ff ff 48 8d 7d 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 3d 01 00 00 8b 45 10 <83> f8 03 74 55 77 1e 83 e8 01 83 f8 01 77 3c c7 45 10 03 00 00 00 RSP: 0018:ffffc90000007d28 EFLAGS: 00000046 RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff815c2ea0 RDX: 1ffff1100ee5e45d RSI: 0000000000000002 RDI: ffff8880772f22e8 RBP: ffff8880772f22d8 R08: ffffffff9048d2a8 R09: 0000000000000003 R10: fffff52000000f93 R11: 0000000000000000 R12: ffff888036623968 R13: dffffc0000000000 R14: 1ffff92000000fa7 R15: ffffffff898de620 FS: 00007f49d8236700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000078ffb000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xb02/0xe50 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:9615 Code: 3c 02 00 0f 85 7a 1a 00 00 48 b8 00 00 00 00 00 00 00 80 49 89 87 80 00 00 00 e8 3c 41 65 00 e8 67 6b 6b 00 fb bf 01 00 00 00 8c ba 3d 00 31 ff 65 44 8b 3d 32 ab f0 7e 44 89 fe e8 ca 49 65 RSP: 0018:ffffc90018267b80 EFLAGS: 00000206 RAX: 00000000006f1399 RBX: 1ffff9200304cf7a RCX: 1ffffffff1fb32d6 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffc90018267ca0 R08: 0000000000000001 R09: ffffffff8fd17b5f R10: 0000000000000001 R11: 0000000000000001 R12: ffff888031764b00 R13: ffff888031764b38 R14: 0000000000000000 R15: 0000000000000000 vcpu_run arch/x86/kvm/x86.c:9700 [inline] kvm_arch_vcpu_ioctl_run+0x4fc/0x21a0 arch/x86/kvm/x86.c:9895 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: 0033:0x7f49dacc0ae9 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:00007f49d8236188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f49dadd3f60 RCX: 00007f49dacc0ae9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 00007f49dad1af25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff7ba6cd5f R14: 00007f49d8236300 R15: 0000000000022000 NMI backtrace for cpu 1 CPU: 1 PID: 11154 Comm: syz-executor.4 Not tainted 5.15.0-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+0x26ba/0x4410 arch/x86/kvm/x86.c:9593 Code: 4c 89 e7 e8 f8 56 0d 00 48 c7 c7 40 52 82 89 e8 2c 75 24 08 65 4c 89 25 4c 9e f0 7e e8 7f 6d 6b 00 fb 49 8d bc 24 e0 20 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f RSP: 0018:ffffc90018287b80 EFLAGS: 00000202 RAX: 00000000006ce9f7 RBX: 1ffff92003050f7a RCX: 1ffffffff1fb32d6 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888037cea7e0 RBP: ffffc90018287ca0 R08: 0000000000000001 R09: ffffffff8fd17b5f R10: 0000000000000001 R11: 0000000000000000 R12: ffff888037ce8700 R13: ffff888037ce8738 R14: 0000000000000000 R15: ffff888037ce8730 vcpu_run arch/x86/kvm/x86.c:9700 [inline] kvm_arch_vcpu_ioctl_run+0x4fc/0x21a0 arch/x86/kvm/x86.c:9895 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: 0033:0x7f9bb75c7ae9 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:00007f9bb4b3d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9bb76daf60 RCX: 00007f9bb75c7ae9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 00007f9bb7621f25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcd456d95f R14: 00007f9bb4b3d300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff 48 8d decl -0x73(%rax) 3: 7d 10 jge 0x15 5: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax c: fc ff df f: 48 89 fa mov %rdi,%rdx 12: 48 c1 ea 03 shr $0x3,%rdx 16: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 1a: 84 c0 test %al,%al 1c: 74 08 je 0x26 1e: 3c 03 cmp $0x3,%al 20: 0f 8e 3d 01 00 00 jle 0x163 26: 8b 45 10 mov 0x10(%rbp),%eax * 29: 83 f8 03 cmp $0x3,%eax <-- trapping instruction 2c: 74 55 je 0x83 2e: 77 1e ja 0x4e 30: 83 e8 01 sub $0x1,%eax 33: 83 f8 01 cmp $0x1,%eax 36: 77 3c ja 0x74 38: c7 45 10 03 00 00 00 movl $0x3,0x10(%rbp)