syzbot

INFO: rcu_sched self-detected stall on CPU
	0-....: (104996 ticks this GP) idle=586/1/4611686018427387906 softirq=32637/32637 fqs=26179 
	 (t=105000 jiffies g=17948 c=17947 q=1510)
NMI backtrace for cpu 0
CPU: 0 PID: 9071 Comm: syz-executor1 Not tainted 4.18.0-rc8+ #182
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+0x1c9/0x2b4 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 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:156 [inline]
 rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1336
 print_cpu_stall kernel/rcu/tree.c:1485 [inline]
 check_cpu_stall.isra.60.cold.78+0x36c/0x5a6 kernel/rcu/tree.c:1553
 __rcu_pending kernel/rcu/tree.c:3244 [inline]
 rcu_pending kernel/rcu/tree.c:3291 [inline]
 rcu_check_callbacks+0x23f/0xcd0 kernel/rcu/tree.c:2646
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1028 [inline]
 smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1053
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:write_comp_data+0x0/0x70
Code: fd ff ff 48 8b bd d0 fe ff ff e8 7b dd 3d 00 e9 ad fc ff ff 4c 89 ef e8 ce dc 3d 00 e9 76 fc ff ff e8 84 1d cb ff 90 90 90 90 <55> 65 4c 8b 04 25 40 ee 01 00 65 8b 05 df d5 85 7e 48 89 e5 a9 00 
RSP: 0018:ffff8801949df738 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000040000 RBX: 000000000006bbcf RCX: ffffffff861748c2
RDX: 000000000006bbcf RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff8801949df740 R08: ffff880195288200 R09: ffff88021fff801b
R10: ffffed0043fff001 R11: 0000000000000000 R12: ffff8801be7e2140
R13: ffff8801d8f99300 R14: dffffc0000000000 R15: ffffed0037cfc526
 ccid_packet_dequeue_eval net/dccp/ccid.h:159 [inline]
 dccp_write_xmit+0xd2/0x1f0 net/dccp/output.c:355
 dccp_sendmsg+0x8db/0x1030 net/dccp/proto.c:816
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:652
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126
 __sys_sendmsg+0x11d/0x290 net/socket.c:2164
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457089
Code: fd 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f0d6e887c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0d6e8886d4 RCX: 0000000000457089
RDX: 0000000004000080 RSI: 00000000200030c0 RDI: 0000000000000005
RBP: 00000000009301e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d3cc0 R14: 00000000004c896e R15: 0000000000000002