------------[ cut here ]------------
kernel BUG at fs/buffer.c:2666!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 27915 Comm: kmmpd-loop0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:submit_bh_wbc+0x4ac/0x4d0 fs/buffer.c:2666
Code: 02 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c c0 fe ff ff 48 89 ef e8 25 f7 e1 ff e9 b3 fe ff ff e8 eb b9 90 ff 0f 0b e8 e4 b9 90 ff <0f> 0b e8 dd b9 90 ff 0f 0b e8 d6 b9 90 ff 0f 0b e8 cf b9 90 ff 0f
RSP: 0018:ffffc90004447ce8 EFLAGS: 00010293
RAX: ffffffff81f187ac RBX: 0000000000000000 RCX: ffff88803cb15a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000003801 R08: ffff88808388548f R09: 1ffff11010710a91
R10: dffffc0000000000 R11: ffffed1010710a92 R12: 1ffff11010710a91
R13: 0000000000000000 R14: ffff888083885488 R15: ffff888073b3a000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f78e45fd64c CR3: 000000007e41a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 write_mmp_block_thawed+0x3ad/0x540 fs/ext4/mmp.c:51
 write_mmp_block+0x129/0x390 fs/ext4/mmp.c:67
 kmmpd+0x342/0x990 fs/ext4/mmp.c:178
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:submit_bh_wbc+0x4ac/0x4d0 fs/buffer.c:2666
Code: 02 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c c0 fe ff ff 48 89 ef e8 25 f7 e1 ff e9 b3 fe ff ff e8 eb b9 90 ff 0f 0b e8 e4 b9 90 ff <0f> 0b e8 dd b9 90 ff 0f 0b e8 d6 b9 90 ff 0f 0b e8 cf b9 90 ff 0f
RSP: 0018:ffffc90004447ce8 EFLAGS: 00010293
RAX: ffffffff81f187ac RBX: 0000000000000000 RCX: ffff88803cb15a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000003801 R08: ffff88808388548f R09: 1ffff11010710a91
R10: dffffc0000000000 R11: ffffed1010710a92 R12: 1ffff11010710a91
R13: 0000000000000000 R14: ffff888083885488 R15: ffff888073b3a000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f78e45fd64c CR3: 000000002453c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400