------------[ cut here ]------------ kernel BUG at fs/buffer.c:2795! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 6557 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+0x566/0x580 fs/buffer.c:2795 Code: e8 af f5 87 ff be 00 10 00 00 48 c7 c7 a0 6f 26 8d 4c 89 ea e8 eb 77 67 02 e9 8b fe ff ff e8 91 f5 87 ff 0f 0b e8 8a f5 87 ff <0f> 0b e8 83 f5 87 ff 0f 0b e8 7c f5 87 ff 0f 0b e8 75 f5 87 ff 0f RSP: 0018:ffffc90003167cc0 EFLAGS: 00010293 RAX: ffffffff81ff7c96 RBX: 0000000000000000 RCX: ffff88802412da00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000003801 R08: ffff88805d19048f R09: 1ffff1100ba32091 R10: dffffc0000000000 R11: ffffed100ba32092 R12: 1ffff1100ba32091 R13: 0000000000000000 R14: ffff88805d190488 R15: ffff88807da9e000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2da1dff8 CR3: 0000000025758000 CR4: 00000000003506f0 Call Trace: write_mmp_block_thawed+0x3b1/0x540 fs/ext4/mmp.c:51 write_mmp_block+0x129/0x390 fs/ext4/mmp.c:67 kmmpd+0x344/0x990 fs/ext4/mmp.c:178 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:submit_bh_wbc+0x566/0x580 fs/buffer.c:2795 Code: e8 af f5 87 ff be 00 10 00 00 48 c7 c7 a0 6f 26 8d 4c 89 ea e8 eb 77 67 02 e9 8b fe ff ff e8 91 f5 87 ff 0f 0b e8 8a f5 87 ff <0f> 0b e8 83 f5 87 ff 0f 0b e8 7c f5 87 ff 0f 0b e8 75 f5 87 ff 0f RSP: 0018:ffffc90003167cc0 EFLAGS: 00010293 RAX: ffffffff81ff7c96 RBX: 0000000000000000 RCX: ffff88802412da00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000003801 R08: ffff88805d19048f R09: 1ffff1100ba32091 R10: dffffc0000000000 R11: ffffed100ba32092 R12: 1ffff1100ba32091 R13: 0000000000000000 R14: ffff88805d190488 R15: ffff88807da9e000 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd9981ef2f8 CR3: 0000000025758000 CR4: 00000000003506f0