10-CURRENT i386 memstick snapshots broken?

[Warren Block]

On Sat, 8 Jun 2013, Glen Barber wrote:

> The problem is creating the gpart(8) partition scheme on the md(4)
> device.
>
> Below follows script(1) output of what the make-memstick.sh script does:
>
>  Script started on Sun Jun  9 00:41:08 2013
>  root at snap:/snap/releng # chroot /snap/releng/10-i386-snap
>  root at snap:/ # cd /usr/obj/usr/src/release
>  root at snap:/usr/obj/usr/src/release # echo \
>    '/dev/ufs/FreeBSD_Install / ufs ro,noatime 1 1' > release/etc/fstab
>  root at snap:/usr/obj/usr/src/release # makefs -B \
>    little -o label=FreeBSD_Install test.img release
>  Calculated size of `test.img': 649420800 bytes, 12922 inodes
>  Extent size set to 8192
>  test.img: 619.3MB (1268400 sectors) block size 8192, fragment size 1024
>  	using 12 cylinder groups of 54.40MB, 6963 blks, 1152 inodes.
>  super-block backups (for fsck -b #) at:
>        32,  111440,  222848,  334256,  445664,  557072,  668480,  779888,
>    891296, 1002704, 1114112, 1225520,
>  Populating `test.img'
>  Image `test.img' complete
>  root at snap:/usr/obj/usr/src/release # mdconfig -a -t vnode -f test.img
>  md0
>
> All fine up until this point.  Now the gpart(8) partition is created:
>
>  root at snap:/usr/obj/usr/src/release # gpart create -s BSD /dev/md0
>  gpart: Inappropriate ioctl for device
>  root at snap:/usr/obj/usr/src/release # gpart list md0
>  Segmentation fault (core dumped)

This might be a good time to stop using a bare bsdlabel (aka 
"dangerously dedicated").  MBR plus bsdlabel is not great, but more 
widely understood, and other operating systems will at least recognize 
the MBR slice.  I can help with this if needed.