diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
index cc393be7e..07649cd3b 100644
--- a/util/grub.d/10_linux.in
+++ b/util/grub.d/10_linux.in
@@ -73,7 +73,7 @@ case x"$GRUB_FS" in
 	    GRUB_CMDLINE_LINUX="rootflags=subvol=${rootsubvol} ${GRUB_CMDLINE_LINUX}"
 	fi;;
     xzfs)
-	rpool=`${grub_probe} --device ${GRUB_DEVICE} --target=fs_label 2>/dev/null || true`
+	rpool=`${grub_probe} --device ${GRUB_DEVICE} --target=fs_label 2>/dev/null || zdb -l ${GRUB_DEVICE} | awk -F \' '/ name/ { print $2 }'`
 	bootfs="`make_system_path_relative_to_its_root / | sed -e "s,@$,,"`"
 	LINUX_ROOT_DEVICE="ZFS=${rpool}${bootfs%/}"
 	;;
diff --git a/util/grub.d/20_linux_xen.in b/util/grub.d/20_linux_xen.in
index 94dd8be13..27bff00a8 100644
--- a/util/grub.d/20_linux_xen.in
+++ b/util/grub.d/20_linux_xen.in
@@ -81,7 +81,7 @@ case x"$GRUB_FS" in
 	    GRUB_CMDLINE_LINUX="rootflags=subvol=${rootsubvol} ${GRUB_CMDLINE_LINUX}"
 	fi;;
     xzfs)
-	rpool=`${grub_probe} --device ${GRUB_DEVICE} --target=fs_label 2>/dev/null || true`
+	rpool=`${grub_probe} --device ${GRUB_DEVICE} --target=fs_label 2>/dev/null || zdb -l ${GRUB_DEVICE} | awk -F \' '/ name/ { print $2 }'`
 	bootfs="`make_system_path_relative_to_its_root / | sed -e "s,@$,,"`"
 	LINUX_ROOT_DEVICE="ZFS=${rpool}${bootfs%/}"
 	;;