rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10500 ticks this GP) idle=f36/1/0x4000000000000000 softirq=284078/284078 fqs=4639 (t=10500 jiffies g=472989 q=119901) NMI backtrace for cpu 1 CPU: 1 PID: 9344 Comm: syz-executor.4 Not tainted 5.8.0-rc6-next-20200721-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:165 [inline] rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3626 [inline] rcu_sched_clock_irq.cold+0x5b3/0xcbd kernel/rcu/tree.c:2509 update_process_times+0x25/0x60 kernel/time/timer.c:1737 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x108/0x290 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1079 [inline] __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1096 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline] sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1090 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:590 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:lock_acquire+0x27b/0xad0 kernel/locking/lockdep.c:5000 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d ea a0 5a 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7 RSP: 0000:ffffc90000da8a78 EFLAGS: 00000286 RAX: 1ffffffff1369ec1 RBX: ffff8882147f4140 RCX: ffffffff8159fd06 RDX: dffffc0000000000 RSI: 1ffff920001b5138 RDI: 0000000000000286 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c654a3f R10: fffffbfff18ca947 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8a894008 R14: 0000000000000000 R15: ffff8882147f4140 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] __dev_xmit_skb net/core/dev.c:3771 [inline] __dev_queue_xmit+0x1756/0x2d60 net/core/dev.c:4107 mrp_queue_xmit net/802/mrp.c:351 [inline] mrp_join_timer+0x8a/0xc0 net/802/mrp.c:595 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers.part.0+0x54c/0xa20 kernel/time/timer.c:1784 __run_timers kernel/time/timer.c:1756 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1797 __do_softirq+0x2df/0xa22 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/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+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1090 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:590 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:lock_acquire+0x27b/0xad0 kernel/locking/lockdep.c:5000 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d ea a0 5a 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7 RSP: 0000:ffffc90001a27618 EFLAGS: 00000286 RAX: 1ffffffff1369ec1 RBX: ffff8882147f4140 RCX: ffffffff8159fd06 RDX: dffffc0000000000 RSI: 1ffff92000344eac RDI: 0000000000000286 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c654a2f R10: fffffbfff18ca945 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880ae731e20 R14: 0000000000000000 R15: ffff8882147f4140 local_lock_acquire include/linux/local_lock_internal.h:39 [inline] activate_page+0x383/0xb10 mm/swap.c:357 mark_page_accessed+0x9c8/0x1020 mm/swap.c:442 zap_pte_range mm/memory.c:1088 [inline] zap_pmd_range mm/memory.c:1195 [inline] zap_pud_range mm/memory.c:1224 [inline] zap_p4d_range mm/memory.c:1245 [inline] unmap_page_range+0xdaf/0x2b20 mm/memory.c:1266 unmap_single_vma+0x198/0x300 mm/memory.c:1311 unmap_vmas+0x16f/0x2f0 mm/memory.c:1343 exit_mmap+0x2b1/0x530 mm/mmap.c:3187 __mmput+0x122/0x470 kernel/fork.c:1075 mmput+0x53/0x60 kernel/fork.c:1096 exit_mm kernel/exit.c:483 [inline] do_exit+0xa8b/0x29f0 kernel/exit.c:793 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x40b/0x1ee0 kernel/signal.c:2743 do_signal+0x82/0x2520 arch/x86/kernel/signal.c:810 exit_to_usermode_loop arch/x86/entry/common.c:235 [inline] __prepare_exit_to_usermode+0x11f/0x1c0 arch/x86/entry/common.c:269 do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ed47 Code: Bad RIP value. RSP: 002b:00007fdbbe0e59c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000029 RAX: 000000000000000b RBX: 00007fdbbe0e5a40 RCX: 000000000045ed47 RDX: 0000000000000010 RSI: 0000000000000003 RDI: 0000000000000010 RBP: 000000000078c070 R08: 0000000000000008 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fdbbe0e5a58 R13: 00007fffc4b6e01f R14: 00007fdbbe0e69c0 R15: 000000000078c04c