On 06/12/2013 08:58 PM, Ben Myers wrote: > On Wed, Jun 12, 2013 at 12:19:07PM +1000, Dave Chinner wrote: >> From: Dave Chinner <dchinner@xxxxxxxxxx> >> >> Michael L. Semon has been testing CRC patches ona 32 bit system and > on a > >> been seeing assert failures in the directory code from xfs/080. >> Thanks to Michael's heroic efforts with printk debugging, we found >> that the problem was that the last free space being left in the >> directory structure was too small to fit a unused tag structure and >> it was being corrupted and attempting to log a region out of bounds. >> Hence the assert failure looked something like: >> >> ..... >> #5 calling xfs_dir2_data_log_unused() 36 32 >> #1 4092 4095 4096 >> #2 8182 8183 4096 > first? > last? > bp->b_length? BBTOB(bp->b_length) This is all terrible numbering on my part... >> #1 4092 4095 4096 >> #2 8182 8183 4096 xfs_dir2_data_log_unused() calls xfs_trans_log_buf() twice in the same function. #1 is the first call, #2 is the second call, and there's no running count. The printk() is a copy-and-paste of those two function calls plus a BBTOB(bp->b_length) below it. >> #5 calling xfs_dir2_data_log_unused() 36 32 The #5 was caused by numbering all the calls to xfs_dir2_data_log_unused() to see if one code path was being called every time. #5 is in the xfs_dir2_data_use_free() function, starting with this else-if... else if (matchfront) { newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); newdup->length = cpu_to_be16(oldlen - len); *xfs_dir2_data_unused_tag_p(newdup) = cpu_to_be16((char *)newdup - (char *)hdr); printk( KERN_INFO "#5 calling xfs_dir2_data_log_unused() %d %d\n", oldlen, len ); xfs_dir2_data_log_unused(tp, bp, newdup); Sorry about that! Michael _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs