EXT4-fs (loop9): pa ffff888123e2a888: logic 0, phys. 193, len 32
EXT4-fs error (device loop9): ext4_mb_release_inode_pa:4876: group 0, free 7, pa_free 16
------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4849!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 609 Comm: syz.9.31 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ext4_mb_release_inode_pa+0xa4e/0xa50 fs/ext4/mballoc.c:4849
Code: 80 c2 03 38 c2 0f 8c 2f fe ff ff 48 89 df 41 89 ce e8 d6 48 c8 ff 44 89 f1 e9 1c fe ff ff e8 39 1c 83 ff 0f 0b e8 32 1c 83 ff <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 b8 38 95 bc ad 55 48 89 e5
RSP: 0018:ffffc900012b6b20 EFLAGS: 00010293
RAX: ffffffff81ee2d8e RBX: 00000000000000fa RCX: ffff88811368d100
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc900012b6c70 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000256d80 R12: 1ffff92000256d7c
R13: dffffc0000000000 R14: 0000000000000060 R15: ffff888123e3f0a8
FS:  00007f67023326c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020020000 CR3: 0000000130fbb000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_mb_discard_group_preallocations+0xbaa/0xdf0 fs/ext4/mballoc.c:4995
 ext4_mb_discard_preallocations fs/ext4/mballoc.c:5564 [inline]
 ext4_mb_discard_preallocations_should_retry+0x15a/0x5e0 fs/ext4/mballoc.c:5585
 ext4_mb_new_blocks+0x30b1/0x4250 fs/ext4/mballoc.c:5788
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0xda7/0x2000 fs/ext4/indirect.c:635
 ext4_map_blocks+0x977/0x1b70 fs/ext4/inode.c:681
 _ext4_get_block+0x1ea/0x540 fs/ext4/inode.c:822
 ext4_get_block+0x39/0x50 fs/ext4/inode.c:839
 ext4_block_write_begin+0x594/0x1280 fs/ext4/inode.c:1124
 ext4_write_begin+0x600/0xf90 fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x3e7/0x8c0 fs/ext4/inode.c:3001
 generic_perform_write+0x300/0x6f0 mm/filemap.c:3887
 ext4_buffered_write_iter+0x36f/0x660 fs/ext4/file.c:285
 ext4_file_write_iter+0x191/0x1500 fs/ext4/file.c:-1
 call_write_iter include/linux/fs.h:2282 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x603/0xce0 fs/read_write.c:584
 ksys_write+0x149/0x250 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f67015903b9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6702332028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f6701795fa0 RCX: 00007f67015903b9
RDX: 0000000000043451 RSI: 0000000020000200 RDI: 0000000000000007
RBP: 00007f670161b9d4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6701795fa0 R15: 00007fff64988d98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_mb_release_inode_pa+0xa4e/0xa50 fs/ext4/mballoc.c:4849
Code: 80 c2 03 38 c2 0f 8c 2f fe ff ff 48 89 df 41 89 ce e8 d6 48 c8 ff 44 89 f1 e9 1c fe ff ff e8 39 1c 83 ff 0f 0b e8 32 1c 83 ff <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 b8 38 95 bc ad 55 48 89 e5
RSP: 0018:ffffc900012b6b20 EFLAGS: 00010293
RAX: ffffffff81ee2d8e RBX: 00000000000000fa RCX: ffff88811368d100
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc900012b6c70 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000256d80 R12: 1ffff92000256d7c
R13: dffffc0000000000 R14: 0000000000000060 R15: ffff888123e3f0a8
FS:  00007f67023326c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020020000 CR3: 0000000130fbb000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400