list_add corruption. next->prev should be prev (ffff88021fffab78), but was ffff88021fffab70. (next=ffff88021fffab70).
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:25!
invalid opcode: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17070 Comm: modprobe Not tainted 4.17.0-rc3+ #92
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_add_valid+0x275/0x450 lib/list_debug.c:23
RSP: 0000:ffff8801c7e7f7c8 EFLAGS: 00010086
RAX: 0000000000000075 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88021fd36eec
RBP: ffff8801c7e7f830 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88021fffab70
R13: ffff88021fffab70 R14: 0000000000000000 R15: ffffffff8b58b000
FS:  00007f72a030a700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88021fbd7a87 CR3: 00000001a752c000 CR4: 00000000001406e0
DR0: 0000000020000040 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 __list_add include/linux/list.h:60 [inline]
 list_add include/linux/list.h:79 [inline]
 __free_one_page+0x1483/0x1800 mm/page_alloc.c:876
 free_one_page mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x87f/0x16b0 mm/page_alloc.c:1260
 __free_pages+0x109/0x240 mm/page_alloc.c:4442
 kmsan_free_page+0x197/0x2e0 mm/kmsan/kmsan.c:938
 free_pages_prepare mm/page_alloc.c:996 [inline]
 __free_pages_ok+0x270/0x16b0 mm/page_alloc.c:1254
 __free_pages mm/page_alloc.c:4442 [inline]
 free_pages+0x1e7/0x320 mm/page_alloc.c:4452
 _pgd_free arch/x86/mm/pgtable.c:367 [inline]
 pgd_free+0x2b2/0x360 arch/x86/mm/pgtable.c:416
 mm_free_pgd kernel/fork.c:551 [inline]
 __mmdrop+0x139/0x930 kernel/fork.c:599
 mmdrop+0xc2/0xd0 include/linux/sched/mm.h:49
 finish_task_switch+0xfe/0x230 kernel/sched/core.c:2723
 context_switch kernel/sched/core.c:2855 [inline]
 __schedule+0x688/0x730 kernel/sched/core.c:3496
 schedule+0x1cc/0x2f0 kernel/sched/core.c:3555
 exit_to_usermode_loop arch/x86/entry/common.c:152 [inline]
 prepare_exit_to_usermode+0x1cc/0x3a0 arch/x86/entry/common.c:196
 retint_user+0x8/0x8
RIP: 0033:0x7f72a00fc760
RSP: 002b:00007ffc342b9720 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000792 RBX: 00007f72a0311ee8 RCX: 00000000000003f3
RDX: 0000000000000389 RSI: 00007f72a03119a8 RDI: 0000000000000000
RBP: 0000000000000002 R08: 000000000391241f R09: 0000000000000036
R10: 00007ffc342b9770 R11: 00007ffc342b9770 R12: 0000000000000004
R13: 00000000e44907f6 R14: 0000000000000000 R15: 00007ffc342b98f8
Code: 87 80 0c 00 00 00 00 00 00 41 c7 87 20 03 00 00 00 00 00 00 48 c7 c7 d4 75 a5 8a 31 c0 48 89 d6 4c 89 ea 4c 89 e1 e8 ab b7 42 fd <0f> 0b 66 0f 1f 84 00 00 00 00 00 eb fe 48 8b 7d c8 e8 75 d1 bf 
RIP: __list_add_valid+0x275/0x450 lib/list_debug.c:23 RSP: ffff8801c7e7f7c8
---[ end trace 8140cdc62871d2a7 ]---