overlayroot_issue

update-grub
/usr/sbin/grub-probe: error: failed to get canonical path of `overlayroot'.

mount
overlayroot on / type overlayfs (rw,lowerdir=/media/root-ro/,upperdir=/media/root-rw/overlay)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/cgroup type tmpfs (rw)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)
none on /sys/fs/pstore type pstore (rw)
/dev/sda1 on /media/root-ro type ext4 (ro,errors=remount-ro)
/media/root-ro/media/floppy0 on /media/floppy0 type overlayfs (rw,lowerdir=/media/root-ro/media/floppy0,upperdir=/media/root-rw/overlay/media/floppy0)
/dev/mmcblk0p1 on /media/root-rw type ext4 (rw,relatime,data=ordered)
systemd on /sys/fs/cgroup/systemd type cgroup (rw,noexec,nosuid,nodev,none,name=systemd)
gvfsd-fuse on /run/user/112/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=lightdm)

df -h
Filesystem                    Size  Used Avail Use% Mounted on
overlayroot                   7.3G   55M  6.8G   1% /
none                          4.0K     0  4.0K   0% /sys/fs/cgroup
udev                          481M  4.0K  481M   1% /dev
tmpfs                          99M  1.1M   98M   2% /run
none                          5.0M     0  5.0M   0% /run/lock
none                          495M   72K  495M   1% /run/shm
none                          100M   12K  100M   1% /run/user
/dev/sda1                     6.3G  5.5G  482M  93% /media/root-ro
/media/root-ro/media/floppy0  7.3G   55M  6.8G   1% /media/floppy0
/dev/mmcblk0p1                7.3G   55M  6.8G   1% /media/root-rw

cat /etc/fstab
#
#  This fstab is in an overlayfs.  The real one can be found at
#  /media/root-ro/etc/fstab
#  The original entry for '/' and other mounts have been updated to be placed
#  under /media/root-ro.
#  To permanently modify this (or any other file), you should change-root into
#  a writable view of the underlying filesystem using:
#      sudo overlayroot-chroot
#
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type>  <options>       <dump>  <pass>
# / was on /dev/sda1 during installation
UUID=d34a6801-deff-4bc2-b132-9091e07a8005 /media/root-ro/ ext4 ro,errors=remount-ro 0 1
/media/root-ro/ / overlayfs lowerdir=/media/root-ro/,upperdir=/media/root-rw/overlay 0 1
# swap was on /dev/sda5 during installation
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /tmp ext4 errors=remount-ro 0 1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /var ext4 errors=remount-ro 0 1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /home ext4 errors=remount-ro 0 1
#overlayroot:swap=0#UUID=bd333f71-8993-4fdb-937a-1604c866651f none swap sw 0 0
/dev/sr0 /media/root-ro/media/floppy0 auto ro,rw,user,noauto,exec,utf8 0 0
/media/root-ro/media/floppy0 /media/floppy0 overlayfs lowerdir=/media/root-ro/media/floppy0,upperdir=/media/root-rw/overlay/media/floppy0 0 0

cat /media/root-ro/etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sda1 during installation
UUID=d34a6801-deff-4bc2-b132-9091e07a8005 /               ext4    errors=remount-ro 0       1
# swap was on /dev/sda5 during installation
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /tmp		ext4	errors=remount-ro 0	1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /var		ext4	errors=remount-ro 0	1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /home		ext4	errors=remount-ro 0	1
UUID=bd333f71-8993-4fdb-937a-1604c866651f none            swap    sw              0       0
/dev/sr0        /media/floppy0  auto    rw,user,noauto,exec,utf8 0       0

cat /media/root-ro/etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sda1 during installation
UUID=d34a6801-deff-4bc2-b132-9091e07a8005 /               ext4    errors=remount-ro 0       1
# swap was on /dev/sda5 during installation
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /tmp		ext4	errors=remount-ro 0	1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /var		ext4	errors=remount-ro 0	1
#UUID=74fc3022-1dfc-4c0d-a1d9-aea7ed5ff614 /home		ext4	errors=remount-ro 0	1
UUID=bd333f71-8993-4fdb-937a-1604c866651f none            swap    sw              0       0
/dev/sr0        /media/floppy0  auto    rw,user,noauto,exec,utf8 0       0

cat /etc/overlayroot.conf
# This is the overlayroot config file
overlayroot_cfgdisk="disabled"
overlayroot="device:dev=/dev/mmcblk0p1"