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| author | Tao Ma <boyu.mt@taobao.com> | 2011-03-23 20:48:11 +0100 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2011-03-23 20:48:11 +0100 |
| commit | 0ba0851714beebb800992e5105a79dc3a4c504b0 (patch) | |
| tree | 290b4f679fc86877df068ae4193101dc583f424f /fs | |
| parent | ext4: unused variables cleanup in fs/ext4/extents.c (diff) | |
| download | linux-0ba0851714beebb800992e5105a79dc3a4c504b0.tar.xz linux-0ba0851714beebb800992e5105a79dc3a4c504b0.zip | |
ext4: fix a BUG in mb_mark_used during trim.
In a bs=4096 volume, if we call FITRIM with the following parameter as
fstrim_range(start = 102400, len = 134144000, minlen = 10240),
we will trigger this BUG_ON:
BUG_ON(start + len > (e4b->bd_sb->s_blocksize << 3));
Mar 4 00:55:52 boyu-tm kernel: ------------[ cut here ]------------
Mar 4 00:55:52 boyu-tm kernel: kernel BUG at fs/ext4/mballoc.c:1506!
Mar 4 01:21:09 boyu-tm kernel: Code: d4 00 00 00 00 49 89 fe 8b 56 0c 44 8b 7e 04 89 55 c4 48 8b 4f 28 89 d6 44 01 fe 48 63 d6 48 8b 41 18 48 c1 e0 03 48 39 c2 76 04 <0f> 0b eb fe 48 8b 55 b0 8b 47 34 3b 42 08 74 04 0f 0b eb fe 48
Mar 4 01:21:09 boyu-tm kernel: RIP [<ffffffffa053eb42>] mb_mark_used+0x47/0x26c [ext4]
Mar 4 01:21:09 boyu-tm kernel: RSP <ffff880121e45c38>
Mar 4 01:21:09 boyu-tm kernel: ---[ end trace 9f461696f6a9dcf2 ]---
Fix this bug by doing the accounting correctly.
Cc: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/mballoc.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index cdc84953f1d4..a5837a837a8b 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4870,10 +4870,15 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) break; } - if (len >= EXT4_BLOCKS_PER_GROUP(sb)) - len -= (EXT4_BLOCKS_PER_GROUP(sb) - first_block); - else + /* + * For all the groups except the last one, last block will + * always be EXT4_BLOCKS_PER_GROUP(sb), so we only need to + * change it for the last group in which case start + + * len < EXT4_BLOCKS_PER_GROUP(sb). + */ + if (first_block + len < EXT4_BLOCKS_PER_GROUP(sb)) last_block = first_block + len; + len -= last_block - first_block; if (e4b.bd_info->bb_free >= minlen) { cnt = ext4_trim_all_free(sb, &e4b, first_block, |