2008-09-08 07:34:29

by Li Zefan

Subject: [PATCH] ext4: miss an unlock in ext4_check_descriptors()

# mkfs.ext3 -m 0 /dev/sda6
# tune2fs -E test_fs -O extents,uninit_bg
(no e2fsck after tune2fs)
# mount -t ext4dev /dev/sda6

oops immediately:

EXT4-fs: ext4_check_descriptors: Checksum for group 0 failed (20091!=0)
EXT4-fs: group descriptors corrupted!

=========================
[ BUG: held lock freed! ]
-------------------------
mount/9422 is freeing memory c6ca0000-c6ca7fff, with a lock still held there!
(&bgl->locks[i].lock#2){--..}, at: [<f8996589>] ext4_fill_super+0xde8/0x1dcf [ext4dev]
2 locks held by mount/9422:
#0: (&type->s_umount_key#19){----}, at: [<c0488258>] sget+0x1dd/0x31c
#1: (&bgl->locks[i].lock#2){--..}, at: [<f8996589>] ext4_fill_super+0xde8/0x1dcf [ext4dev]

Signed-off-by: Li Zefan <[email protected]>
---
fs/ext4/super.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 566344b..24e7df6 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1623,8 +1623,10 @@ static int ext4_check_descriptors(struct super_block *sb)
"Checksum for group %lu failed (%u!=%u)\n",
i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
gdp)), le16_to_cpu(gdp->bg_checksum));
- if (!(sb->s_flags & MS_RDONLY))
+ if (!(sb->s_flags & MS_RDONLY)) {
+ spin_unlock(sb_bgl_lock(sbi, i));
return 0;
+ }
}
spin_unlock(sb_bgl_lock(sbi, i));
if (!flexbg_flag)
-- 1.5.4.rc3

2008-09-08 14:48:53

by Theodore Ts'o

Subject: Re: [PATCH] ext4: miss an unlock in ext4_check_descriptors()

Thanks, I've applied it to the ext4 patch queue.

- Ted