diff --git a/src/cmd/linuxkit/run_hyperkit.go b/src/cmd/linuxkit/run_hyperkit.go
index c909ff650..4fdf5f9d2 100644
--- a/src/cmd/linuxkit/run_hyperkit.go
+++ b/src/cmd/linuxkit/run_hyperkit.go
@@ -92,7 +92,9 @@ func runHyperKit(args []string) {
 			*isoBoot = true
 			prefix = strings.TrimSuffix(path, ".iso")
 			// hyperkit only supports UEFI ISO boot at present
-			*uefiBoot = true
+			if !*uefiBoot {
+				log.Fatalf("Hyperkit requires --uefi to be set to boot an ISO")
+			}
 		}
 	}
 
diff --git a/src/cmd/linuxkit/run_qemu.go b/src/cmd/linuxkit/run_qemu.go
index 3f7fc013c..b18fa20c0 100644
--- a/src/cmd/linuxkit/run_qemu.go
+++ b/src/cmd/linuxkit/run_qemu.go
@@ -174,11 +174,6 @@ func runQemu(args []string) {
 			*isoBoot = true
 			prefix = strings.TrimSuffix(path, ".iso")
 		}
-		// autodetect EFI ISO from our default naming
-		if strings.HasSuffix(path, "-efi.iso") {
-			*uefiBoot = true
-			prefix = strings.TrimSuffix(path, "-efi.iso")
-		}
 	}
 
 	if *state == "" {