rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (11288 ticks this GP) idle=6ca/1/0x4000000000000002 softirq=10244/10246 fqs=5246 
	(t=10500 jiffies g=8025 q=53)
NMI backtrace for cpu 1
CPU: 1 PID: 9173 Comm: syz-executor062 Not tainted 5.2.0-rc6-next-20190628 #25
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+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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+0x183/0x1cf kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2736 [inline]
 rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183
 update_process_times+0x32/0x80 kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296
 __run_hrtimer kernel/time/hrtimer.c:1388 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1450
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1508
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1066
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x1/0x50 kernel/kcov.c:95
Code: 25 e4 a4 16 09 41 bc f4 ff ff ff e8 ad a6 e9 ff 48 c7 05 ce a4 16 09 00 00 00 00 e9 77 e9 ff ff 90 90 90 90 90 90 90 90 90 55 <48> 89 e5 65 48 8b 04 25 c0 fd 01 00 65 8b 15 34 a0 8f 7e 81 e2 00
RSP: 0018:ffff88809b707108 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 00000000000000a0 RCX: ffffffff81f83b80
RDX: 0000000000000000 RSI: ffffffff81f844ed RDI: ffff88812c27629c
RBP: ffff88809b707210 R08: ffff88808bd4e280 R09: ffffed101132275a
R10: ffffed1011322759 R11: ffff888089913acf R12: 0000000000000000
R13: 0000000000000000 R14: ffff8880899138f0 R15: ffff88812c276200
 ext4_mark_inode_dirty+0x255/0x9b0 fs/ext4/inode.c:6072
 ext4_dirty_inode+0x8f/0xc0 fs/ext4/inode.c:6103
 __mark_inode_dirty+0x68e/0x1390 fs/fs-writeback.c:2167
 mark_inode_dirty include/linux/fs.h:2138 [inline]
 __generic_write_end+0xad/0x130 fs/buffer.c:2155
 generic_write_end+0x74/0x1a0 fs/buffer.c:2199
 ext4_da_write_end+0x205/0xa50 fs/ext4/inode.c:3211
 generic_perform_write+0x2fe/0x530 mm/filemap.c:3286
 __generic_file_write_iter+0x25e/0x630 mm/filemap.c:3404
 ext4_file_write_iter+0x373/0x1430 fs/ext4/file.c:270
 call_write_iter include/linux/fs.h:1870 [inline]
 do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693
 do_iter_write fs/read_write.c:970 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:951
 vfs_iter_write+0x77/0xb0 fs/read_write.c:983
 iter_file_splice_write+0x66d/0xbe0 fs/splice.c:746
 do_splice_from fs/splice.c:848 [inline]
 direct_splice_actor+0x123/0x190 fs/splice.c:1020
 splice_direct_to_actor+0x366/0x970 fs/splice.c:975
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1063
 do_sendfile+0x597/0xd00 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1519 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1511
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440229
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffd60d2308 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440229
RDX: 0000000020000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00008080fffffffe R11: 0000000000000246 R12: 0000000000401ab0
R13: 0000000000401b40 R14: 0000000000000000 R15: 0000000000000000