EXT4-fs error (device loop2): ext4_mb_generate_buddy:1102: group 0, block bitmap and bg descriptor inconsistent: 0 vs 150994969 free clusters
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kernel BUG at fs/ext4/inode.c:2761!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 963 Comm: syz.2.105 Not tainted 6.1.145-syzkaller-1169984-g3b4ff5af8d36 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ext4_writepages+0x2ff8/0x3020 fs/ext4/inode.c:2760
Code: a0 86 ff 84 db 75 31 e8 36 9d 86 ff 49 bc 00 00 00 00 00 fc ff df 4c 8b 7c 24 18 4c 8b 6c 24 38 e9 a2 f7 ff ff e8 18 9d 86 ff <0f> 0b e8 11 9d 86 ff e8 38 15 17 ff eb 93 e8 05 9d 86 ff e8 2c 15
RSP: 0018:ffffc900016d7680 EFLAGS: 00010293

RAX: ffffffff81e96568 RBX: 000000d410000000 RCX: ffff888106715100
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900016d79f0 R08: dffffc0000000000 R09: ffffed10257bf39e
R10: ffffed10257bf39e R11: 1ffff110257bf39d R12: dffffc0000000000
R13: ffff88812bdf9e00 R14: 0000008000000000 R15: ffff88812bdf9ce8
FS:  000055556d2d7500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0955b69160 CR3: 00000001308c1000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 do_writepages+0x3a9/0x5e0 mm/page-writeback.c:2494
 filemap_fdatawrite_wbc+0x128/0x190 mm/filemap.c:408
 __filemap_fdatawrite_range mm/filemap.c:441 [inline]
 __filemap_fdatawrite mm/filemap.c:447 [inline]
 filemap_flush+0xc1/0x110 mm/filemap.c:474
 ext4_alloc_da_blocks+0x7a/0x190 fs/ext4/inode.c:3165
 ext4_release_file+0x84/0x320 fs/ext4/file.c:158
 __fput+0x1fc/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1db/0x240 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f03bdb85d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc54e21608 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000001092d RCX: 00007f03bdb85d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f03bdd77ba0 R08: 0000000000000001 R09: 00007ffc54e218ff
R10: 00007f03bd800000 R11: 0000000000000246 R12: 0000000000010a5b
R13: 00007f03bdd75fa0 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_writepages+0x2ff8/0x3020 fs/ext4/inode.c:2760
Code: a0 86 ff 84 db 75 31 e8 36 9d 86 ff 49 bc 00 00 00 00 00 fc ff df 4c 8b 7c 24 18 4c 8b 6c 24 38 e9 a2 f7 ff ff e8 18 9d 86 ff <0f> 0b e8 11 9d 86 ff e8 38 15 17 ff eb 93 e8 05 9d 86 ff e8 2c 15
RSP: 0018:ffffc900016d7680 EFLAGS: 00010293
RAX: ffffffff81e96568 RBX: 000000d410000000 RCX: ffff888106715100
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900016d79f0 R08: dffffc0000000000 R09: ffffed10257bf39e
R10: ffffed10257bf39e R11: 1ffff110257bf39d R12: dffffc0000000000
R13: ffff88812bdf9e00 R14: 0000008000000000 R15: ffff88812bdf9ce8
FS:  000055556d2d7500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0955b69160 CR3: 00000001308c1000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400