rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=3d2/1/0x4000000000000000 softirq=66667/66668 fqs=4883 (t=10500 jiffies g=117885 q=623) NMI backtrace for cpu 1 CPU: 1 PID: 8304 Comm: syz-executor.2 Not tainted 5.10.0-rc2-next-20201106-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+0x107/0x163 lib/dump_stack.c:118 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:165 [inline] rcu_dump_cpu_stacks+0x1e3/0x21e kernel/rcu/tree_stall.h:337 print_cpu_stall kernel/rcu/tree_stall.h:569 [inline] check_cpu_stall kernel/rcu/tree_stall.h:643 [inline] rcu_pending kernel/rcu/tree.c:3752 [inline] rcu_sched_clock_irq.cold+0x472/0xec3 kernel/rcu/tree.c:2581 update_process_times+0x77/0xd0 kernel/time/timer.c:1709 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1519 [inline] __hrtimer_run_queues+0x1ce/0xea0 kernel/time/hrtimer.c:1583 hrtimer_interrupt+0x334/0x940 kernel/time/hrtimer.c:1645 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1097 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline] sysvec_apic_timer_interrupt+0x48/0x100 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:__slab_alloc.constprop.0+0x55/0xe0 mm/slub.c:2788 Code: 21 05 35 07 83 f8 07 89 c2 77 6e 48 03 1c d5 c0 f6 e3 8a 4c 89 f9 44 89 f2 44 89 ee 48 89 ef 49 89 d8 e8 be f3 ff ff 41 54 9d <48> 83 c4 08 5b 5d 41 5c 41 5d 41 5e 41 5f c3 e8 a7 80 c4 ff 48 8b RSP: 0018:ffffc90000d90b70 EFLAGS: 00000282 RAX: ffff888157e00000 RBX: ffff8880b9f38710 RCX: ffffffff8155a027 RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000000 RBP: ffff888010042000 R08: 0000000000000001 R09: ffffffff8ebb3737 R10: fffffbfff1d766e6 R11: 0000000000000000 R12: 0000000000000282 R13: 0000000000082a20 R14: 00000000ffffffff R15: ffffffff870e5454 slab_alloc_node mm/slub.c:2865 [inline] __kmalloc_node_track_caller+0x1c4/0x420 mm/slub.c:4525 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0xac/0x630 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1094 [inline] mrp_pdu_init net/802/mrp.c:300 [inline] mrp_pdu_append_vecattr_event+0x7b4/0x1020 net/802/mrp.c:399 mrp_attr_event+0x191/0x280 net/802/mrp.c:494 mrp_mad_event net/802/mrp.c:574 [inline] mrp_join_timer+0x5a/0xc0 net/802/mrp.c:591 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1410 expire_timers kernel/time/timer.c:1455 [inline] __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1747 __run_timers kernel/time/timer.c:1728 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1760 __do_softirq+0x2a0/0x9f6 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x132/0x200 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:generic_exec_single+0x215/0x350 kernel/smp.c:295 Code: 48 89 dd 31 ff 81 e5 00 02 00 00 48 89 ee e8 b2 34 0b 00 48 85 ed 75 1a e8 38 3c 0b 00 4c 89 f7 41 ff d5 e8 2d 3c 0b 00 53 9d <45> 31 e4 e9 e4 fe ff ff e8 1e 3c 0b 00 e8 89 01 11 00 4c 89 f7 41 RSP: 0018:ffffc90001cb7b08 EFLAGS: 00000246 RAX: 0000000000000433 RBX: 0000000000000246 RCX: ffffc9000db6f000 RDX: 0000000000040000 RSI: ffffffff8164e243 RDI: 0000000000000000 RBP: 0000000000000200 R08: 0000000000000001 R09: ffffffff8ebb3787 R10: fffffbfff1d766f0 R11: 0000000000000000 R12: ffffc90001cb7b80 R13: ffffffff818b1910 R14: ffffc90001cb7c50 R15: 1ffff92000396f9e smp_call_function_single+0x1a4/0x4b0 kernel/smp.c:509 task_function_call+0xd4/0x160 kernel/events/core.c:116 perf_install_in_context+0x2cb/0x550 kernel/events/core.c:2914 __do_sys_perf_event_open+0x1c31/0x2cb0 kernel/events/core.c:12021 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45deb9 Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff38d4cec78 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 0000000000024d40 RCX: 000000000045deb9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000180 RBP: 000000000118bf70 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffff55a67cf R14: 00007ff38d4cf9c0 R15: 000000000118bf2c