diff --git a/tools/fast-run.sh b/tools/fast-run.sh
index 74401249..3adbb091 100755
--- a/tools/fast-run.sh
+++ b/tools/fast-run.sh
@@ -5,4 +5,11 @@ source $(dirname $0)/env.sh
 
 cd $LUNA_ROOT
 
-qemu-system-$LUNA_ARCH -cdrom Luna.iso -smp 1 -m 256M -serial stdio -enable-kvm $@
+if [ -c /dev/kvm ]
+then
+EXTRA_FLAGS="-enable-kvm"
+else
+EXTRA_FLAGS=""
+fi
+
+qemu-system-$LUNA_ARCH -cdrom Luna.iso -smp 1 -m 256M -serial stdio $EXTRA_FLAGS $@