While investigating PR196390 I encountered an error during the creation of a small filesystem: % (cd /; makefs ~/image ~/metalog) Calculated size of `/home/emaste/image': 131072 bytes, 8 inodes Extent size set to 32768 /home/emaste/image: 0.1MB (256 sectors) block size 32768, fragment size 4096 using 1 cylinder groups of 0.12MB, 4 blks, 256 inodes. super-block backups (for fsck -b #) at: 64, Populating `/home/emaste/image' makefs: ffs_alloccg: map corrupted: start 1 len 3 offset 206 206 metalog contained the example from PR196390, . type=dir uname=root gname=wheel mode=0755 ./etc type=dir uname=root gname=wheel mode=0755 ./sbin type=dir uname=root gname=wheel mode=0755 ./usr type=dir uname=root gname=wheel mode=0755 ./usr/bin type=dir uname=root gname=wheel mode=0755 ./usr/bin/passwd type=file uname=root gname=wheel mode=04555 size=7000 ./etc/passwd type=file mode=0644 uname=root gname=wheel