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list_add corruption. next->prev should be prev (ffffe8ffffc31ed0), but was ffff88803a6e7000. (next=ffff88801fbef400).
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kernel BUG at lib/list_debug.c:31!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 30 Comm: kworker/u4:2 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: zswap1 compact_page_work
RIP: 0010:__list_add_valid_or_report+0xd6/0xf0 lib/list_debug.c:29
Code: e8 9f 66 00 07 90 0f 0b 48 c7 c7 c0 04 61 8c e8 90 66 00 07 90 0f 0b 48 c7 c7 20 05 61 8c 4c 89 e6 4c 89 f1 e8 7b 66 00 07 90 <0f> 0b 48 c7 c7 a0 05 61 8c 4c 89 f6 4c 89 e1 e8 66 66 00 07 90 0f
RSP: 0000:ffffc9000050fad0 EFLAGS: 00010246
RAX: 0000000000000075 RBX: ffff88801fbef408 RCX: 0023d31b53ac3b00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffe8ffffc31ed0 R08: ffffffff8174b16c R09: 1ffff920000a1ef4
R10: dffffc0000000000 R11: fffff520000a1ef5 R12: ffffe8ffffc31ed0
R13: dffffc0000000000 R14: ffff88801fbef400 R15: ffff888041930000
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0068cf000 CR3: 0000000042fa8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __list_add_valid include/linux/list.h:88 [inline]
 __list_add include/linux/list.h:150 [inline]
 list_add include/linux/list.h:169 [inline]
 add_to_unbuddied+0x2e4/0x4d0 mm/z3fold.c:550
 do_compact_page+0x924/0xc50 mm/z3fold.c:772
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_add_valid_or_report+0xd6/0xf0 lib/list_debug.c:29
Code: e8 9f 66 00 07 90 0f 0b 48 c7 c7 c0 04 61 8c e8 90 66 00 07 90 0f 0b 48 c7 c7 20 05 61 8c 4c 89 e6 4c 89 f1 e8 7b 66 00 07 90 <0f> 0b 48 c7 c7 a0 05 61 8c 4c 89 f6 4c 89 e1 e8 66 66 00 07 90 0f
RSP: 0000:ffffc9000050fad0 EFLAGS: 00010246
RAX: 0000000000000075 RBX: ffff88801fbef408 RCX: 0023d31b53ac3b00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffe8ffffc31ed0 R08: ffffffff8174b16c R09: 1ffff920000a1ef4
R10: dffffc0000000000 R11: fffff520000a1ef5 R12: ffffe8ffffc31ed0
R13: dffffc0000000000 R14: ffff88801fbef400 R15: ffff888041930000
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0068cf000 CR3: 0000000042fa8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400