print_req_error: I/O error, dev loop3, sector 0 EXT4-fs (loop3): mount failed ------------[ cut here ]------------ kernel BUG at fs/buffer.c:3049! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 11898 Comm: kmmpd-loop3 Not tainted 4.19.200-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:submit_bh_wbc+0x5e5/0x760 fs/buffer.c:3049 Code: 10 4c 8d 7b 20 48 89 44 24 08 e9 3e fc ff ff e8 81 8b b1 ff f0 80 63 01 f7 e9 4d fb ff ff e8 72 8b b1 ff 0f 0b e8 6b 8b b1 ff <0f> 0b e8 64 8b b1 ff 0f 0b e8 5d 8b b1 ff 0f 0b e8 56 8b b1 ff 0f RSP: 0018:ffff88803e57fd78 EFLAGS: 00010293 RAX: ffff8880983a4200 RBX: ffff888043765540 RCX: ffffffff81b0f1b1 RDX: 0000000000000000 RSI: ffffffff81b0f725 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000003800 R13: 0000000000000000 R14: 0000000000000001 R15: 00000000ffffe184 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000014a53ad CR3: 0000000048928000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: write_mmp_block+0x1e4/0x310 fs/ext4/mmp.c:55 kmmpd+0x71f/0xa80 fs/ext4/mmp.c:246 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Modules linked in: ---[ end trace 06c9494229998908 ]--- RIP: 0010:submit_bh_wbc+0x5e5/0x760 fs/buffer.c:3049 Code: 10 4c 8d 7b 20 48 89 44 24 08 e9 3e fc ff ff e8 81 8b b1 ff f0 80 63 01 f7 e9 4d fb ff ff e8 72 8b b1 ff 0f 0b e8 6b 8b b1 ff <0f> 0b e8 64 8b b1 ff 0f 0b e8 5d 8b b1 ff 0f 0b e8 56 8b b1 ff 0f RSP: 0018:ffff88803e57fd78 EFLAGS: 00010293 RAX: ffff8880983a4200 RBX: ffff888043765540 RCX: ffffffff81b0f1b1 RDX: 0000000000000000 RSI: ffffffff81b0f725 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 audit: type=1800 audit(1628035604.634:27): pid=11924 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.1" name="file0" dev="loop1" ino=4 res=0 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000003800 R13: 0000000000000000 R14: 0000000000000001 R15: 00000000ffffe184 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000499c40 CR3: 000000009d99f000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400