rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
rcu: 	1-...!: (10501 ticks this GP) idle=942/1/0x4000000000000002 softirq=19872/19919 fqs=25 
rcu: 	(detected by 0, t=10502 jiffies, g=285, q=2)
Sending NMI from CPU 0 to CPUs 1:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.087 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 9888 Comm: syz-executor2 Not tainted 4.19.0-rc8+ #290
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x50 kernel/kcov.c:100
Code: c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 55 48 89 e5 65 48 8b 04 25 40 ee 01 00 <65> 8b 15 6c 44 83 7e 81 e2 00 01 1f 00 48 8b 75 08 75 2b 8b 90 d0
RSP: 0018:ffff8801daf07e30 EFLAGS: 00000086
RAX: ffff880183b7a240 RBX: ffff8801daf1f630 RCX: 1ffffffff12013dd
RDX: dffffc0000000000 RSI: ffffffff838d2358 RDI: ffffffff89009ee8
RBP: ffff8801daf07e30 R08: ffff880183b7a240 R09: 1ffffffff1273955
R10: ffffed003b5e4732 R11: ffff8801daf23993 R12: ffff880183b7a240
R13: ffff8801daf07fc0 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f8dda290700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a40021 CR3: 00000001c6eee000 CR4: 00000000001406e0
Call Trace:
 <IRQ>
 debug_smp_processor_id+0x9/0x20 lib/smp_processor_id.c:56
 irqtime_account_irq+0x63/0x290 kernel/sched/cputime.c:58
 account_irq_exit_time include/linux/vtime.h:114 [inline]
 irq_exit+0x4f/0x1c0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1056
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xaf/0xd0 kernel/locking/spinlock.c:184
Code: 08 f2 31 89 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 28 48 83 3d 70 a1 81 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb ad e8 fc 2c 50 f9 eb bb 0f 0b 0f 0b e8 ca c4 11
RSP: 0018:ffff880180817528 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 1ffff1003076f55c
RDX: 1ffffffff1263e41 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff880180817538 R08: ffff880183b7aae0 R09: 0000000000000006
R10: 0000000000000000 R11: ffff880183b7a240 R12: ffff8801d2b318e0
R13: ffff880180817660 R14: 0000000000000000 R15: 0000000000000282
 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline]
 __skb_try_recv_datagram+0x236/0x5b0 net/core/datagram.c:272
 unix_dgram_recvmsg+0x2e4/0x1b10 net/unix/af_unix.c:2103
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0xd0/0x110 net/socket.c:801
 __sys_recvfrom+0x311/0x5d0 net/socket.c:1845
 __do_sys_recvfrom net/socket.c:1863 [inline]
 __se_sys_recvfrom net/socket.c:1859 [inline]
 __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1859
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8dda28fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569
RDX: 0000000000000044 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000020003640 R09: 0000000000472479
R10: 100000000001005e R11: 0000000000000246 R12: 00007f8dda2906d4
R13: 00000000004c31d8 R14: 00000000004d4d28 R15: 00000000ffffffff
rcu: rcu_sched kthread starved for 10423 jiffies! g285 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_sched       R  running task    23272    11      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804
 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=942/1/0x4000000000000002 softirq=19918/19919 fqs=1 
rcu: 	(detected by 0, t=10537 jiffies, g=17825, q=66)
Sending NMI from CPU 0 to CPUs 1:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.586 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 9888 Comm: syz-executor2 Not tainted 4.19.0-rc8+ #290
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x50 kernel/kcov.c:100
Code: c1 01 4a 89 7c 10 e0 4a 89 74 10 e8 4a 89 54 10 f0 4a 89 4c d8 20 4c 89 08 5d c3 66 90 55 48 89 e5 65 48 8b 04 25 40 ee 01 00 <65> 8b 15 6c 44 83 7e 81 e2 00 01 1f 00 48 8b 75 08 75 2b 8b 90 d0
RSP: 0018:ffff8801daf075b8 EFLAGS: 00000006
RAX: ffff880183b7a240 RBX: 0000000000010002 RCX: ffffffff838d234a
RDX: 0000000000010000 RSI: ffffffff838d2353 RDI: 0000000000000005
RBP: ffff8801daf075b8 R08: ffff880183b7a240 R09: ffffed003b5e4732
R10: ffff8801daf076c0 R11: ffff8801daf23993 R12: 0000000000000001
R13: ffffffff88408e40 R14: ffffffff88408e00 R15: ffff8801daf07940
FS:  00007f8dda290700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a40021 CR3: 00000001c6eee000 CR4: 00000000001406e0
Call Trace:
 <IRQ>
 check_preemption_disabled+0x48/0x200 lib/smp_processor_id.c:51
 debug_smp_processor_id+0x1c/0x20 lib/smp_processor_id.c:56
 rcu_dynticks_curr_cpu_in_eqs+0x69/0x160 kernel/rcu/tree.c:348
 rcu_is_watching+0x10/0x30 kernel/rcu/tree.c:1025
 rcu_read_unlock include/linux/rcupdate.h:679 [inline]
 __perf_event_output kernel/events/core.c:6516 [inline]
 perf_event_output_forward+0x239/0x2d0 kernel/events/core.c:6524
 __perf_event_overflow+0x239/0x4c0 kernel/events/core.c:7768
 perf_swevent_hrtimer+0x35f/0x510 kernel/events/core.c:9126
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline]
 smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xaf/0xd0 kernel/locking/spinlock.c:184
Code: 08 f2 31 89 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 28 48 83 3d 70 a1 81 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb ad e8 fc 2c 50 f9 eb bb 0f 0b 0f 0b e8 ca c4 11
RSP: 0018:ffff880180817528 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 1ffff1003076f55c
RDX: 1ffffffff1263e41 RSI: 0000000000000000 RDI: 0000000000000282
RBP: ffff880180817538 R08: ffff880183b7aae0 R09: 0000000000000006
R10: 0000000000000000 R11: ffff880183b7a240 R12: ffff8801d2b318e0
R13: ffff880180817660 R14: 0000000000000000 R15: 0000000000000282
 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline]
 __skb_try_recv_datagram+0x236/0x5b0 net/core/datagram.c:272
 unix_dgram_recvmsg+0x2e4/0x1b10 net/unix/af_unix.c:2103
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0xd0/0x110 net/socket.c:801
 __sys_recvfrom+0x311/0x5d0 net/socket.c:1845
 __do_sys_recvfrom net/socket.c:1863 [inline]
 __se_sys_recvfrom net/socket.c:1859 [inline]
 __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1859
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8dda28fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569
RDX: 0000000000000044 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000020003640 R09: 0000000000472479
R10: 100000000001005e R11: 0000000000000246 R12: 00007f8dda2906d4
R13: 00000000004c31d8 R14: 00000000004d4d28 R15: 00000000ffffffff
rcu: rcu_preempt kthread starved for 10520 jiffies! g17825 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    22736    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804
 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413