diff -r bbceb6297329 -r 92c101eebe25 src/arch/x86/system.cc
--- a/src/arch/x86/system.cc	Sun Apr 15 12:35:49 2012 -0700
+++ b/src/arch/x86/system.cc	Wed Apr 18 01:45:48 2012 -0700
@@ -114,6 +114,9 @@
 {
     System::initState();
 
+    if (!kernel)
+        fatal("No kernel to load.\n");
+
     if (kernel->getArch() == ObjectFile::I386)
         fatal("Loading a 32 bit x86 kernel is not supported.\n");