rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10499 ticks this GP) idle=916/1/0x4000000000000002 softirq=10527/10527 fqs=5224 
	(t=10500 jiffies g=13461 q=1590)
NMI backtrace for cpu 0
CPU: 0 PID: 8598 Comm: syz-executor.5 Not tainted 5.7.0-rc1-next-20200415-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:165 [inline]
 rcu_dump_cpu_stacks+0x19b/0x1e5 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:475 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:549 [inline]
 rcu_pending kernel/rcu/tree.c:3225 [inline]
 rcu_sched_clock_irq.cold+0x55d/0xd00 kernel/rcu/tree.c:2296
 update_process_times+0x25/0x60 kernel/time/timer.c:1727
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x4e/0x140 kernel/time/tick-sched.c:1320
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x5ca/0xed0 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0x15b/0x600 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:check_memory_region+0x124/0x190 mm/kasan/generic.c:194
Code: 89 c8 4d 39 c8 74 0f 41 80 38 00 74 ee 49 8d 04 1c 4d 85 c0 75 15 49 89 e9 49 29 c1 e9 52 ff ff ff 5b b8 01 00 00 00 5d 41 5c <c3> 4d 39 c3 75 12 4d 0f be 03 41 83 e2 07 b8 01 00 00 00 4d 39 c2
RSP: 0018:ffffc90016ea7138 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 00000000000001e2 RCX: ffffffff818c0969
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88808e1e60b8
RBP: ffff88808e1e60b8 R08: ffff88809562a580 R09: ffffed1011c3cc18
R10: ffff88808e1e60bf R11: ffffed1011c3cc17 R12: dffffc0000000000
R13: ffff88808e1e6000 R14: ffffc90016ea7298 R15: ffffc90016ea7498
 instrument_atomic_read include/linux/instrumented.h:56 [inline]
 atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline]
 perf_event_count kernel/events/core.c:4229 [inline]
 perf_output_read_group kernel/events/core.c:6692 [inline]
 perf_output_read+0xbe9/0x11f0 kernel/events/core.c:6729
 perf_output_sample+0xe17/0x1c20 kernel/events/core.c:6776
 __perf_event_output kernel/events/core.c:7157 [inline]
 perf_event_output_forward+0x12f/0x270 kernel/events/core.c:7171
 __perf_event_overflow+0x13c/0x370 kernel/events/core.c:8736
 perf_swevent_overflow+0xac/0x150 kernel/events/core.c:8812
 perf_swevent_event+0x1e9/0x2e0 kernel/events/core.c:8845
 do_perf_sw_event kernel/events/core.c:8953 [inline]
 ___perf_sw_event+0x31c/0x570 kernel/events/core.c:8984
 __perf_sw_event+0x4b/0xa0 kernel/events/core.c:8996
 perf_sw_event include/linux/perf_event.h:1158 [inline]
 do_user_addr_fault arch/x86/mm/fault.c:1501 [inline]
 do_page_fault+0xb07/0x13da arch/x86/mm/fault.c:1535
 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x30 arch/x86/lib/copy_user_64.S:205
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 1f 00 c3 0f 1f 80 00 00 00 00 0f 1f 00 83 fa 40 0f 82 70 ff ff ff 89 d1 <f3> a4 31 c0 0f 1f 00 c3 66 2e 0f 1f 84 00 00 00 00 00 89 d1 f3 a4
RSP: 0018:ffffc90016ea7a58 EFLAGS: 00010206
RAX: 0000000000000001 RBX: 0000000000008000 RCX: 0000000000004fcb
RDX: 0000000000008000 RSI: 0000000020fe0000 RDI: ffff888056f9b035
RBP: ffff888056f98000 R08: ffffed100adf4000 R09: 0000000000000000
R10: ffff888056f9ffff R11: ffffed100adf3fff R12: 0000000020fdcfcb
R13: 0000000020fe4fcb R14: 00007ffffffff000 R15: 0000000000000000
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:68 [inline]
 copyin+0x107/0x140 lib/iov_iter.c:152
 _copy_from_iter_full+0x20a/0x870 lib/iov_iter.c:790
 copy_from_iter_full include/linux/uio.h:156 [inline]
 skb_do_copy_data_nocache include/net/sock.h:2036 [inline]
 skb_copy_to_page_nocache include/net/sock.h:2062 [inline]
 tcp_sendmsg_locked+0x131a/0x3210 net/ipv4/tcp.c:1335
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1433
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 __sys_sendto+0x220/0x330 net/socket.c:2000
 __do_sys_sendto net/socket.c:2012 [inline]
 __se_sys_sendto net/socket.c:2008 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2008
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29
Code: 0d b7 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 b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007efcd28cfc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000005011c0 RCX: 000000000045ca29
RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0f0000000000e803
R10: 0000000000000240 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a0e R14: 00000000004cce56 R15: 00007efcd28d06d4