syzbot

==================================================================
BUG: KASAN: stack-out-of-bounds in update_min_vruntime+0x182/0x1a0 kernel/sched/fair.c:521
Read of size 8 at addr ffff88019fa386d8 by task syz-executor2/4449

CPU: 0 PID: 4449 Comm: syz-executor2 Not tainted 4.18.0-rc3+ #47
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
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
PANIC: double fault, error_code: 0x0
 update_min_vruntime+0x182/0x1a0 kernel/sched/fair.c:521
CPU: 1 PID: 10520 Comm: syz-executor3 Not tainted 4.18.0-rc3+ #47
 update_curr+0x200/0xc00 kernel/sched/fair.c:826
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0x2e/0x5020 kernel/locking/lockdep.c:3294
Code: 
41 
57 
41 
89 
 enqueue_entity+0x40d/0x2130 kernel/sched/fair.c:4195
cf 
41 
56 
41 
55 
49 
89 
fd 41 
54 45 
89 
cc 
53 
65 
 enqueue_task_fair+0x22d/0x910 kernel/sched/fair.c:5408
4c 8b 
34 25 
40 
ee 01 
00 48 
 enqueue_task kernel/sched/core.c:751 [inline]
 activate_task+0x123/0x2e0 kernel/sched/core.c:770
83 e4 
 ttwu_activate kernel/sched/core.c:1659 [inline]
 ttwu_do_activate+0xd5/0x1f0 kernel/sched/core.c:1718
f0 
 ttwu_queue kernel/sched/core.c:1863 [inline]
 try_to_wake_up+0x948/0x12b0 kernel/sched/core.c:2076
48 81 
ec 
60 03 
00 
00 
48 8b 
45 
10 <89> 
94 
24 
80 
00 00 
00 
 wake_up_process+0x10/0x20 kernel/sched/core.c:2149
48 
 hrtimer_wakeup+0x48/0x60 kernel/time/hrtimer.c:1647
ba 
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460
00 
00 
00 
00 
00 
fc 
ff 
df 
48 89 84 24 
98 
 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518
RSP: 0018:ffff8801987ffda0 EFLAGS: 00010086
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1050
RAX: 0000000000000000 RBX: 1ffff10033100030 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff88f92620
RBP: ffff880198800128 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88019fdc71b8 R11: ffff8801daf236b3 R12: 0000000000000000
R13: ffffffff88f92620 R14: ffff8801bd6662c0 R15: 0000000000000002
FS:  00007fd5108e0700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
CR2: ffff8801987ffd98 CR3: 00000001a2982000 CR4: 00000000001406e0
 </IRQ>
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
RIP: 0010:arch_atomic_inc arch/x86/include/asm/atomic.h:96 [inline]
RIP: 0010:atomic_inc include/asm-generic/atomic-instrumented.h:103 [inline]
RIP: 0010:get_bh include/linux/buffer_head.h:283 [inline]
RIP: 0010:ext4_mark_iloc_dirty+0x1f5/0x30b0 fs/ext4/inode.c:5769
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Code: 
Call Trace:
c1