on 3/20/2023 8:44 PM, Jan Kara wrote: > On Tue 21-02-23 19:59:19, Kemeng Shi wrote: >> As inode table blocks are contiguous, inode table blocks inside the >> block_group can be represented as range [itbl_cluster_start, >> itbl_cluster_last]. Then we can simply account inode table cluters and >> check cluster overlap with [itbl_cluster_start, itbl_cluster_last] instead >> of traverse each block of inode table. >> By the way, this patch fixes code style problem of comment for >> ext4_num_overhead_clusters. >> >> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> > > FWIW this is triggering Coverity warning: > > *** CID 1536792: Uninitialized variables (UNINIT) > /fs/ext4/balloc.c: 153 in ext4_num_overhead_clusters() > 147 inode_cluster = EXT4_B2C(sbi, > 148 ext4_inode_bitmap(sb, gdp) - st > 149 /* > 150 * Additional check if inode bitmap is in just accounted > 151 * block_cluster > 152 */ >>>> CID 1536792: Uninitialized variables (UNINIT) >>>> Using uninitialized value "block_cluster". > 153 if (inode_cluster != block_cluster && > 154 inode_cluster >= base_clusters && > 155 (inode_cluster < itbl_cluster_start || > 156 inode_cluster > itbl_cluster_end)) > 157 num_clusters++; > 158 } > > which actually looks valid AFAICT. Yes, there is a risk to access uninitialized block_cluster if block bitmap block and inode bitmap block are in different groups. Patch to fix is just sent. Thanks! -- Best wishes Kemeng Shi
