rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=1ad/1/0x4000000000000000 softirq=113169/113169 fqs=8 (t=10502 jiffies g=176361 q=855) rcu: rcu_preempt kthread starved for 10485 jiffies! g176361 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:28888 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: 8728 Comm: syz-executor.0 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197 Code: 01 f0 4d 89 03 e9 63 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 69 9e 8c 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900000077f8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000170 RCX: 00000000000003e8 RDX: 0000000000000000 RSI: ffff888152640280 RDI: 0000000000000003 RBP: ffff8881520c8000 R08: 0000000000000170 R09: ffff8881520c845b R10: ffffffff81931dfd R11: 0000000000000000 R12: 0000000000000000 R13: ffff8881520c8210 R14: 00000000000003e8 R15: 0000000000000000 FS: 00007fc82d499700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc82d499a08 CR3: 000000015b379000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __perf_event_account_interrupt+0xa9/0x2c0 kernel/events/core.c:9101 __perf_event_overflow+0xb1/0x3d0 kernel/events/core.c:9137 perf_swevent_hrtimer+0x37c/0x3f0 kernel/events/core.c:10543 __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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] RIP: 0010:_raw_spin_unlock+0x1/0x40 kernel/locking/spinlock.c:186 Code: 00 31 c9 45 31 c9 41 b8 01 00 00 00 ba 01 00 00 00 31 f6 e8 41 ac 23 f8 58 44 89 e0 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 55 <48> 8b 74 24 08 48 89 fd 48 83 c7 18 e8 fe a4 23 f8 48 89 ef e8 46 RSP: 0018:ffffc90000007cf8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888018cb1cf0 RCX: 0000000000000100 RDX: ffff888152640280 RSI: ffffffff873aeef3 RDI: ffff888018cb1cb0 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000003 R10: fffff52000000f93 R11: 0000000000000000 R12: ffff888018cb1c00 R13: ffff888018cb1cb0 R14: ffffffff873aee80 R15: 0000000000000000 spin_unlock include/linux/spinlock.h:403 [inline] mrp_join_timer+0x7b/0xc0 net/802/mrp.c:606 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:write_comp_data kernel/kcov.c:217 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0xc/0x80 kernel/kcov.c:270 Code: e8 48 c7 44 38 e0 06 00 00 00 48 89 4c 38 f0 4e 89 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 53 41 89 fb 41 89 f1 bf 03 00 00 00 <65> 48 8b 0c 25 40 f0 01 00 48 89 ce 4c 8b 54 24 08 e8 de ef ff ff RSP: 0018:ffffc900028d7be0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880761c7d00 RCX: ffffc90002209000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: dffffc0000000000 R08: 0000000000004c00 R09: 0000000000000000 R10: ffffffff83a77b18 R11: 0000000000000000 R12: ffffc900028d7cb8 R13: ffff888072596f10 R14: 0000000000000000 R15: 0000000000000000 tomoyo_check_acl+0xcb/0x450 security/tomoyo/domain.c:173 tomoyo_path_number_perm+0x32a/0x590 security/tomoyo/file.c:733 security_file_ioctl+0x50/0xb0 security/security.c:1540 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0xb3/0x200 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: 0033:0x4663b7 Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 48 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 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:00007fc82d498f48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc82d4996bc RCX: 00000000004663b7 RDX: 0000000000000006 RSI: 0000000000004c00 RDI: 0000000000000007 RBP: 0000000000000007 R08: 0000000000000000 R09: ffffffff00000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000010 R13: 0000000000000006 R14: 0000000020000780 R15: 0000000000000000 NMI backtrace for cpu 1 CPU: 1 PID: 8729 Comm: syz-executor.1 Not tainted 5.14.0-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:105 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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 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:194 Code: 74 24 10 e8 4a a4 23 f8 48 89 ef e8 92 1a 24 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 03 dc 17 f8 65 8b 05 2c f7 ca 76 85 c0 74 0a 5b 5d c3 e8 50 81 RSP: 0018:ffffc90000fd8c28 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000200 RCX: 1ffffffff1adcdf1 RDX: 0000000000000000 RSI: ffffffff817b7a81 RDI: 0000000000000001 RBP: ffff8880b9d20240 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff817b7a68 R11: 0000000000000000 R12: 000000010001555c R13: ffff8880b9d20240 R14: 0000000000000000 R15: 00000000ffffffff __mod_timer+0x837/0xe30 kernel/time/timer.c:1065 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:757 [inline] __dev_queue_xmit+0x1bbc/0x3710 net/core/dev.c:4229 __netlink_deliver_tap_skb net/netlink/af_netlink.c:303 [inline] __netlink_deliver_tap net/netlink/af_netlink.c:321 [inline] netlink_deliver_tap+0x9cb/0xc30 net/netlink/af_netlink.c:334 netlink_deliver_tap_kernel net/netlink/af_netlink.c:343 [inline] netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x5e5/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 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: 0033:0x4665f9 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:00007f843536b188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000005 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffc851225af R14: 00007f843536b300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 01 f0 add %esi,%eax 2: 4d 89 03 mov %r8,(%r11) 5: e9 63 fd ff ff jmpq 0xfffffd6d a: b9 ff ff ff ff mov $0xffffffff,%ecx f: ba 08 00 00 00 mov $0x8,%edx 14: 4d 8b 03 mov (%r11),%r8 17: 48 0f bd ca bsr %rdx,%rcx 1b: 49 8b 45 00 mov 0x0(%r13),%rax 1f: 48 63 c9 movslq %ecx,%rcx 22: e9 64 ff ff ff jmpq 0xffffff8b 27: 0f 1f 00 nopl (%rax) * 2a: 65 8b 05 69 9e 8c 7e mov %gs:0x7e8c9e69(%rip),%eax # 0x7e8c9e9a <-- trapping instruction 31: 89 c1 mov %eax,%ecx 33: 48 8b 34 24 mov (%rsp),%rsi 37: 81 e1 00 01 00 00 and $0x100,%ecx 3d: 65 gs 3e: 48 rex.W 3f: 8b .byte 0x8b