svn commit: r280840 - head/release/tools

[NGie Cooper]

On Mon, Mar 30, 2015 at 1:33 AM, Colin Percival <cperciva at freebsd.org> wrote:
> Author: cperciva
> Date: Mon Mar 30 08:33:19 2015
> New Revision: 280840
> URL: https://svnweb.freebsd.org/changeset/base/280840
>
> Log:
>   Clean up filesystem unmounting in vmimage builds:
>   * Remove vm_umount_base function which is currently unused.
>   * Add umount_loop function which loops attempting to unmount one filesystem.
>   * Replace calls to umount with calls to umount_loop.
>   * Don't attempt to unmount ${DESTDIR}/dev if it isn't mounted.
>
>   The looping is necessary because sometimes umount fails due to filesystems
>   being busy.  The most common cause of such busyness is periodic(8) jobs
>   running `find / ...`.
>
>   Reviewed by:  gjb
>
> Modified:
>   head/release/tools/vmimage.subr
>
> Modified: head/release/tools/vmimage.subr
> ==============================================================================
> --- head/release/tools/vmimage.subr     Mon Mar 30 07:11:49 2015        (r280839)
> +++ head/release/tools/vmimage.subr     Mon Mar 30 08:33:19 2015        (r280840)
> @@ -45,8 +45,10 @@ err() {
>  }
>
>  cleanup() {
> -       umount ${DESTDIR}/dev 2>/dev/null
> -       umount ${DESTDIR}
> +       if mount | grep -qE "devfs on ${DESTDIR}/dev"; then
> +               umount_loop ${DESTDIR}/dev 2>/dev/null
> +       fi

if [ -c "${DESTDIR}/dev" ]; then
    umount_loop
fi

etc, is probably more foolproof here.