rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10498 ticks this GP) idle=276/1/0x4000000000000004 softirq=118059/118059 fqs=5 (t=10501 jiffies g=171025 q=88) rcu: rcu_preempt kthread starved for 10492 jiffies! g171025 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 28952 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0x9b2/0x18d0 kernel/rcu/tree.c:1821 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 13224 Comm: syz-executor.1 Not tainted 5.5.0-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:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq.cold+0x509/0xc0d kernel/rcu/tree.c:2271 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x90/0xe0 kernel/locking/spinlock.c:191 Code: 48 c7 c0 d8 34 93 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d cf f3 bb 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 b1 79 79 f9 65 8b 05 62 dd 2a 78 RSP: 0018:ffffc90000da8bc8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff132669b RBX: 0000000000000282 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282 RBP: ffffc90000da8bd8 R08: 1ffffffff165ebbb R09: fffffbfff165ebbc R10: fffffbfff165ebbb R11: ffffffff8b2f5ddf R12: ffff8880ae927240 R13: ffff8880ae927240 R14: ffff8880ae927240 R15: ffff8880ae927240 __mod_timer kernel/time/timer.c:1057 [inline] mod_timer+0x507/0xc10 kernel/time/timer.c:1100 mrp_join_timer_arm+0x5e/0x80 net/802/mrp.c:583 mrp_join_timer+0x79/0x80 net/802/mrp.c:596 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:preempt_schedule_irq+0xab/0x160 kernel/sched/core.c:4338 Code: 00 00 e8 78 aa 7a f9 e8 e3 96 a4 f9 4c 89 f0 48 c1 e8 03 80 3c 18 00 75 7d 48 83 3d 36 0f bd 01 00 74 6f fb 66 0f 1f 44 00 00 01 00 00 00 e8 ab d1 ff ff 48 c7 c0 e0 34 93 89 48 c1 e8 03 80 RSP: 0018:ffffc9000875f8b8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff132669d RBX: dffffc0000000000 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888056e0cd14 RBP: ffffc9000875f8d8 R08: 1ffffffff165eba7 R09: fffffbfff165eba8 R10: fffffbfff165eba7 R11: ffffffff8b2f5d3f R12: ffffed100adc1890 R13: ffff888056e0c480 R14: ffffffff899334e8 R15: 0000000000000000 retint_kernel+0x1b/0x2b RIP: 0010:__kasan_check_read+0x1/0x20 mm/kasan/common.c:95 Code: bf 1c 06 8b 5d c4 e9 55 9e ff ff 48 8b 73 58 89 c2 48 c7 c7 48 3b 42 89 f7 da e8 de b9 ab ff e9 3e ef ff ff cc cc cc cc cc 55 <89> f6 31 d2 48 89 e5 48 8b 4d 08 e8 1f 2a 00 00 5d c3 0f 1f 00 66 RSP: 0018:ffffc9000875f990 EFLAGS: 00000216 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: 0000000000000028 RCX: ffffc900049c9000 RDX: 00000000000156dc RSI: 0000000000000028 RDI: ffffc9000875fa30 RBP: ffffc9000875f9d0 R08: ffff888056e0c480 R09: ffff888056e0cd10 R10: fffffbfff14f70f8 R11: ffffffff8a7b87c7 R12: 00000000007160a8 R13: ffffc9000875fa30 R14: 00000000007160d0 R15: 00007ffffffff000 copy_to_user include/linux/uaccess.h:152 [inline] inet_gifconf+0x23c/0x490 net/ipv4/devinet.c:1268 dev_ifconf+0xd0/0x230 net/core/dev_ioctl.c:80 sock_do_ioctl+0x260/0x2f0 net/socket.c:1054 sock_ioctl+0x3ed/0x790 net/socket.c:1191 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45af49 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fd77d100c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045af49 RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000007 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd77d1016d4 R13: 00000000004c4f66 R14: 00000000004dba00 R15: 00000000ffffffff