==================================================================
BUG: KASAN: stack-out-of-bounds in deref_stack_reg+0x1b8/0x1d0
Read of size 8 at addr ffff8801d4f3f8c8 by task syz-executor6/2065

CPU: 1 PID: 2065 Comm: syz-executor6 Not tainted 4.14.0-rc5-mm1+ #17
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 dump_stack+0x173/0x237
 print_address_description+0x6e/0x250
 kasan_report+0x251/0x340
 deref_stack_reg+0x1b8/0x1d0
 unwind_next_frame+0xebc/0x1df0
 __save_stack_trace+0x6e/0xd0
 save_stack+0x32/0xb0
 kasan_slab_free+0x71/0xc0
 kmem_cache_free+0x72/0x280
 rcu_process_callbacks+0xcd4/0x1600
 __do_softirq+0x2ba/0xafb
 irq_exit+0x1c7/0x200
 smp_apic_timer_interrupt+0x154/0x6b0
 apic_timer_interrupt+0x96/0xa0
 </IRQ>
RIP: 0010:lock_is_held_type+0x84/0x200
RSP: 0018:ffff8801d4f3f680 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff11
RAX: dffffc0000000000 RBX: ffff8801caf2c000 RCX: 0000000000000000
RDX: 1ffffffff0ad8f48 RSI: 00000000ffffffff RDI: ffffffff856c7a40
RBP: ffffed0035cc1f68 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff85737ce0
R13: ffff8801ae60fb40 R14: ffff8801cb39d590 R15: ffff8801ae606380
 kvm_put_kvm+0x24f/0xcd0

The buggy address belongs to the page:
page:ffffea000753cfc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x200000000000000()
raw: 0200000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d4f3f780: f2 f2 f2 04 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2
 ffff8801d4f3f800: f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2
>ffff8801d4f3f880: f2 f2 f2 00 f2 f2 f2 f3 f3 f3 f3 00 00 00 00 00
                                              ^
 ffff8801d4f3f900: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f8
 ffff8801d4f3f980: f2 f2 f2 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00
==================================================================