------------[ cut here ]------------ kernel BUG at fs/buffer.c:2666! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 4427 Comm: kmmpd-loop0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:submit_bh_wbc+0x4ac/0x4d0 fs/buffer.c:2666 Code: 01 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c c0 fe ff ff 48 89 ef e8 d5 68 e2 ff e9 b3 fe ff ff e8 7b 4c 92 ff 0f 0b e8 74 4c 92 ff <0f> 0b e8 6d 4c 92 ff 0f 0b e8 66 4c 92 ff 0f 0b e8 5f 4c 92 ff 0f RSP: 0018:ffffc900032d7cc8 EFLAGS: 00010293 RAX: ffffffff81ee83ac RBX: 0000000000000000 RCX: ffff888075ad8000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000003801 R08: dffffc0000000000 R09: ffffed100e111997 R10: ffffed100e111997 R11: 1ffff1100e111996 R12: 1ffff1100e111996 R13: 0000000000000000 R14: ffff88807088ccb0 R15: ffff88807a39a000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0fbd9e0000 CR3: 000000002e29f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: write_mmp_block_thawed+0x360/0x4f0 fs/ext4/mmp.c:51 write_mmp_block+0x13e/0x3a0 fs/ext4/mmp.c:67 kmmpd+0x6f7/0x980 fs/ext4/mmp.c:246 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:submit_bh_wbc+0x4ac/0x4d0 fs/buffer.c:2666 Code: 01 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c c0 fe ff ff 48 89 ef e8 d5 68 e2 ff e9 b3 fe ff ff e8 7b 4c 92 ff 0f 0b e8 74 4c 92 ff <0f> 0b e8 6d 4c 92 ff 0f 0b e8 66 4c 92 ff 0f 0b e8 5f 4c 92 ff 0f RSP: 0018:ffffc900032d7cc8 EFLAGS: 00010293 RAX: ffffffff81ee83ac RBX: 0000000000000000 RCX: ffff888075ad8000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000003801 R08: dffffc0000000000 R09: ffffed100e111997 R10: ffffed100e111997 R11: 1ffff1100e111996 R12: 1ffff1100e111996 R13: 0000000000000000 R14: ffff88807088ccb0 R15: ffff88807a39a000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0fbd9e0000 CR3: 000000007d8e1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400