On Thu, 29 May 2008 11:21:18 +0800 Shen Feng <shen@xxxxxxxxxxxxxx> wrote: > The error processing of the return value of mb_free_blocks > is meanless because it only return 0. This fix includes > *make mb_free_blocks return void > *remove the error processing part in callers This: > *unlock group before calling ext4_error in mb_free_blocks fixes a potential deadlock. > @@ -1084,11 +1084,12 @@ static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b, > blocknr += block; > blocknr += > le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); > - > + ext4_unlock_group(sb, e4b->bd_group); > ext4_error(sb, __func__, "double-free of inode" > " %lu's block %llu(bit %u in group %lu)\n", > inode ? inode->i_ino : 0, blocknr, block, > e4b->bd_group); > + ext4_lock_group(sb, e4b->bd_group); > } > mb_clear_bit(block, EXT4_MB_BITMAP(e4b)); > e4b->bd_info->bb_counters[order]++; but are we sure we can just drop the lock and then cheerfully proceed? Whatever data that lock is protecting might have changed.. A safer-looking fix would be to return an error from mb_free_blocks() and handle the in the caller, once the ext4_unlock_group() has been performed. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
