------------[ cut here ]------------ kernel BUG at fs/buffer.c:2714! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 383 Comm: kmmpd-loop0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:submit_bh_wbc+0x4c9/0x4f0 fs/buffer.c:2714 Code: c3 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c bd fe ff ff 48 89 df e8 38 dc e7 ff e9 b0 fe ff ff e8 de a9 a2 ff 0f 0b e8 d7 a9 a2 ff <0f> 0b e8 d0 a9 a2 ff 0f 0b e8 c9 a9 a2 ff 0f 0b e8 c2 a9 a2 ff 0f RSP: 0018:ffffc9000e7bfca0 EFLAGS: 00010293 RAX: ffffffff81cec329 RBX: 0000000000000000 RCX: ffff888114755100 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000e7bfcf0 R08: ffff888133070157 R09: 1ffff1102660e02a R10: dffffc0000000000 R11: ffffed102660e02b R12: 0000000000000000 R13: 1ffff1102660e02a R14: ffff888133070150 R15: 0000000000003801 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f546038dd30 CR3: 000000012f435000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: submit_bh+0x1f/0x30 fs/buffer.c:2755 write_mmp_block_thawed+0x397/0x510 fs/ext4/mmp.c:51 write_mmp_block+0x138/0x2b0 fs/ext4/mmp.c:67 kmmpd+0x215/0x950 fs/ext4/mmp.c:246 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:submit_bh_wbc+0x4c9/0x4f0 fs/buffer.c:2714 Code: c3 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c bd fe ff ff 48 89 df e8 38 dc e7 ff e9 b0 fe ff ff e8 de a9 a2 ff 0f 0b e8 d7 a9 a2 ff <0f> 0b e8 d0 a9 a2 ff 0f 0b e8 c9 a9 a2 ff 0f 0b e8 c2 a9 a2 ff 0f RSP: 0018:ffffc9000e7bfca0 EFLAGS: 00010293 RAX: ffffffff81cec329 RBX: 0000000000000000 RCX: ffff888114755100 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000e7bfcf0 R08: ffff888133070157 R09: 1ffff1102660e02a R10: dffffc0000000000 R11: ffffed102660e02b R12: 0000000000000000 R13: 1ffff1102660e02a R14: ffff888133070150 R15: 0000000000003801 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa0619e9e80 CR3: 000000000700f000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400