rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10499 ticks this GP) idle=8be/1/0x4000000000000002 softirq=16091/16091 fqs=5248 
rcu: 	 (t=10502 jiffies g=14221 q=1052)
NMI backtrace for cpu 1
CPU: 1 PID: 9785 Comm: syz-executor.4 Not tainted 4.19.57 #30
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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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+0x189/0x1d5 kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x5e3/0xd93 kernel/rcu/tree.c:2682
 update_process_times+0x32/0x80 kernel/time/timer.c:1636
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:164
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x33b/0xdd0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1054
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:869
 </IRQ>
RIP: 0010:write_comp_data+0x68/0x70 kernel/kcov.c:146
Code: 00 00 4e 8d 14 dd 28 00 00 00 4d 39 d0 72 1b 49 83 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 <c3> 0f 1f 80 00 00 00 00 55 40 0f b6 d6 40 0f b6 f7 31 ff 48 89 e5
RSP: 0018:ffff88805eb27048 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: 00000000000004e0 RCX: ffffffff817fe13a
RDX: 00000000000004d0 RSI: 0000000000000000 RDI: 0000000000000007
RBP: ffff88805eb27050 R08: ffff88805c95c240 R09: ffffed1012d64166
R10: ffffed1012d64165 R11: ffff888096b20b2f R12: 0000000000000010
R13: dffffc0000000000 R14: ffff88805eb271c0 R15: ffff88805eb273c8
 __output_copy kernel/events/internal.h:176 [inline]
 perf_output_read_group kernel/events/core.c:6155 [inline]
 perf_output_read+0xe4a/0x1390 kernel/events/core.c:6188
 perf_output_sample+0x13b6/0x1a90 kernel/events/core.c:6230
 __perf_event_output kernel/events/core.c:6552 [inline]
 perf_event_output_forward+0x150/0x290 kernel/events/core.c:6565
 __perf_event_overflow+0x141/0x370 kernel/events/core.c:7811
 perf_swevent_overflow+0xaa/0x140 kernel/events/core.c:7887
 perf_swevent_event+0x1f7/0x2f0 kernel/events/core.c:7920
 do_perf_sw_event kernel/events/core.c:8028 [inline]
 ___perf_sw_event+0x31c/0x570 kernel/events/core.c:8059
 __perf_sw_event+0x51/0xa0 kernel/events/core.c:8071
 perf_sw_event include/linux/perf_event.h:1059 [inline]
 __do_page_fault+0x7a6/0xe90 arch/x86/mm/fault.c:1434
 do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1468
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1181
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x20 arch/x86/lib/copy_user_64.S:181
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 0f 1f 00 83
RSP: 0018:ffff88805eb27a10 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000008000 RCX: 0000000000007aeb
RDX: 0000000000008000 RSI: 0000000020ff6000 RDI: ffff88805d5b0515
RBP: ffff88805eb27a48 R08: ffffed100bab7000 R09: 0000000000000000
R10: ffffed100bab6fff R11: ffff88805d5b7fff R12: 0000000020ff5aeb
R13: ffff88805d5b0000 R14: 0000000020ffdaeb R15: 00007ffffffff000
 _copy_from_iter_full+0x1f2/0x820 lib/iov_iter.c:724
 copy_from_iter_full include/linux/uio.h:124 [inline]
 skb_do_copy_data_nocache include/net/sock.h:1960 [inline]
 skb_copy_to_page_nocache include/net/sock.h:1986 [inline]
 tcp_sendmsg_locked+0x134b/0x3550 net/ipv4/tcp.c:1338
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1443
 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 __sys_sendto+0x262/0x380 net/socket.c:1787
 __do_sys_sendto net/socket.c:1799 [inline]
 __se_sys_sendto net/socket.c:1795 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1795
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4597c9
Code: fd 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f22e0db1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004597c9
RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000040000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f22e0db26d4
R13: 00000000004c75c5 R14: 00000000004dcb48 R15: 00000000ffffffff
rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
rcu: 	1-....: (10528 ticks this GP) idle=8be/1/0x4000000000000000 softirq=16075/16091 fqs=5231 
rcu: 	(detected by 0, t=10532 jiffies, g=277, q=2)
Sending NMI from CPU 0 to CPUs 1:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.197 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 9785 Comm: syz-executor.4 Not tainted 4.19.57 #30
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:memcpy+0x28/0x50 mm/kasan/kasan.c:303
Code: 66 90 55 48 89 e5 41 56 49 89 f6 48 8b 4d 08 41 55 49 89 fd 4c 89 f7 41 54 49 89 d4 31 d2 4c 89 e6 e8 7c f7 ff ff 48 8b 4d 08 <4c> 89 e6 4c 89 ef ba 01 00 00 00 e8 68 f7 ff ff 4c 89 e2 4c 89 f6
RSP: 0018:ffff88805eb27038 EFLAGS: 00000246
RAX: ffffed100bd64e38 RBX: 00000000000003f0 RCX: ffffffff817fe106
RDX: 0000000000000000 RSI: 0000000000000010 RDI: ffff88805eb271b0
RBP: ffff88805eb27050 R08: 1ffff1100bd64e36 R09: ffffed100bd64e38
R10: ffffed100bd64e37 R11: ffff88805eb271bf R12: 0000000000000010
R13: ffff88809168fc10 R14: ffff88805eb271b0 R15: ffff88805eb273c8
FS:  00007f22e0db2700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020ff6000 CR3: 0000000064036000 CR4: 00000000001406e0
Call Trace:
 memcpy include/linux/string.h:348 [inline]
 memcpy_common kernel/events/internal.h:172 [inline]
 __output_copy kernel/events/internal.h:176 [inline]
 perf_output_read_group kernel/events/core.c:6155 [inline]
 perf_output_read+0xe16/0x1390 kernel/events/core.c:6188
 perf_output_sample+0x13b6/0x1a90 kernel/events/core.c:6230
 __perf_event_output kernel/events/core.c:6552 [inline]
 perf_event_output_forward+0x150/0x290 kernel/events/core.c:6565
 __perf_event_overflow+0x141/0x370 kernel/events/core.c:7811
 perf_swevent_overflow+0xaa/0x140 kernel/events/core.c:7887
 perf_swevent_event+0x1f7/0x2f0 kernel/events/core.c:7920
 do_perf_sw_event kernel/events/core.c:8028 [inline]
 ___perf_sw_event+0x31c/0x570 kernel/events/core.c:8059
 __perf_sw_event+0x51/0xa0 kernel/events/core.c:8071
 perf_sw_event include/linux/perf_event.h:1059 [inline]
 __do_page_fault+0x7a6/0xe90 arch/x86/mm/fault.c:1434
 do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1468
 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1181
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x20 arch/x86/lib/copy_user_64.S:181
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 0f 1f 00 83
RSP: 0018:ffff88805eb27a10 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000008000 RCX: 0000000000007aeb
RDX: 0000000000008000 RSI: 0000000020ff6000 RDI: ffff88805d5b0515
RBP: ffff88805eb27a48 R08: ffffed100bab7000 R09: 0000000000000000
R10: ffffed100bab6fff R11: ffff88805d5b7fff R12: 0000000020ff5aeb
R13: ffff88805d5b0000 R14: 0000000020ffdaeb R15: 00007ffffffff000
 _copy_from_iter_full+0x1f2/0x820 lib/iov_iter.c:724
 copy_from_iter_full include/linux/uio.h:124 [inline]
 skb_do_copy_data_nocache include/net/sock.h:1960 [inline]
 skb_copy_to_page_nocache include/net/sock.h:1986 [inline]
 tcp_sendmsg_locked+0x134b/0x3550 net/ipv4/tcp.c:1338
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1443
 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 __sys_sendto+0x262/0x380 net/socket.c:1787
 __do_sys_sendto net/socket.c:1799 [inline]
 __se_sys_sendto net/socket.c:1795 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1795
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4597c9
Code: fd 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f22e0db1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004597c9
RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000040000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f22e0db26d4
R13: 00000000004c75c5 R14: 00000000004dcb48 R15: 00000000ffffffff