------------[ cut here ]------------
kernel BUG at fs/buffer.c:2666!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 6756 Comm: kmmpd-loop0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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 e5 09 e2 ff e9 b3 fe ff ff e8 fb 1e 91 ff 0f 0b e8 f4 1e 91 ff <0f> 0b e8 ed 1e 91 ff 0f 0b e8 e6 1e 91 ff 0f 0b e8 df 1e 91 ff 0f
RSP: 0018:ffffc90005467cc8 EFLAGS: 00010293
RAX: ffffffff81f1537c RBX: 0000000000000000 RCX: ffff888025558000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000003801 R08: ffff8880725dc747 R09: 1ffff1100e4bb8e8
R10: dffffc0000000000 R11: ffffed100e4bb8e9 R12: 1ffff1100e4bb8e8
R13: 0000000000000000 R14: ffff8880725dc740 R15: ffff88801ee6a000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd23ffc CR3: 000000000c88e000 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+0x13e/0x3a0 fs/ext4/mmp.c:67
 kmmpd+0x337/0x980 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 e5 09 e2 ff e9 b3 fe ff ff e8 fb 1e 91 ff 0f 0b e8 f4 1e 91 ff <0f> 0b e8 ed 1e 91 ff 0f 0b e8 e6 1e 91 ff 0f 0b e8 df 1e 91 ff 0f
RSP: 0018:ffffc90005467cc8 EFLAGS: 00010293
RAX: ffffffff81f1537c RBX: 0000000000000000 RCX: ffff888025558000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000003801 R08: ffff8880725dc747 R09: 1ffff1100e4bb8e8
R10: dffffc0000000000 R11: ffffed100e4bb8e9 R12: 1ffff1100e4bb8e8
R13: 0000000000000000 R14: ffff8880725dc740 R15: ffff88801ee6a000
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f18ef7e8400 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400