From 0a71bc39954894c2c63b7a3fc249c00f62f3a3ba Mon Sep 17 00:00:00 2001
From: Aiken Harris <harraiken91@gmail.com>
Date: Wed, 15 Oct 2025 20:55:16 +0200
Subject: [PATCH] Print fallback message in non-EFI environment

---
 boot/xtldr/xtldr.cc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/boot/xtldr/xtldr.cc b/boot/xtldr/xtldr.cc
index 2e960f6..3e0cac9 100644
--- a/boot/xtldr/xtldr.cc
+++ b/boot/xtldr/xtldr.cc
@@ -236,6 +236,15 @@ BlStartXtLoader(IN EFI_HANDLE ImageHandle,
     PWCHAR Modules;
     EFI_STATUS Status;
 
+    /* Check if system is EFI-based and provided parameters are valid */
+    if(ImageHandle == NULLPTR || SystemTable == NULLPTR)
+    {
+        /* Invalid parameters, print error message using BIOS calls and hang */
+        BiosUtils::ClearScreen();
+        BiosUtils::Print(L"XTLDR requires EFI-based system!");
+        for(;;);
+    }
+
     /* Initialize XTLDR and */
     XtLoader::InitializeBootLoader(ImageHandle, SystemTable);