diff --git a/vm-initramfs/lib/dracut/hooks/pre-udev/90_qubes_cow_setup.sh b/vm-initramfs/lib/dracut/hooks/pre-udev/90_qubes_cow_setup.sh
index fa1616f..19bb9d3 100755
--- a/vm-initramfs/lib/dracut/hooks/pre-udev/90_qubes_cow_setup.sh
+++ b/vm-initramfs/lib/dracut/hooks/pre-udev/90_qubes_cow_setup.sh
@@ -14,18 +14,18 @@ modprobe xenblk || modprobe xen-blkfront || echo "Qubes: Cannot load Xen Block F
 echo "Waiting for /dev/xvda* devices..."
 while ! [ -e /dev/xvda ]; do sleep 0.1; done
 
-if [ `blockdev --getro /dev/xvda` = 1 ] ; then
+if [ `cat /sys/block/xvda/ro` = 1 ] ; then
 	echo "Qubes: Doing COW setup for AppVM..."
 
 	while ! [ -e /dev/xvdc ]; do sleep 0.1; done
 	while ! [ -e /dev/xvdc2 ]; do sleep 0.1; done
 
-	echo "0 `blockdev --getsz /dev/xvda` snapshot /dev/xvda /dev/xvdc2 N 16" | \
+	echo "0 `cat /sys/block/xvda/size` snapshot /dev/xvda /dev/xvdc2 N 16" | \
     		dmsetup create dmroot || { echo "Qubes: FATAL: cannot create dmroot!"; }
 	echo Qubes: done.
 else
 	echo "Qubes: Doing R/W setup for TemplateVM..."
-	echo "0 `blockdev --getsz /dev/xvda` linear /dev/xvda 0" | \
+	echo "0 `cat /sys/block/xvda/size` linear /dev/xvda 0" | \
     		dmsetup create dmroot || { echo "Qubes: FATAL: cannot create dmroot!"; exit 1; }
 	echo Qubes: done.
 fi