diff --git a/pkgs/os-specific/linux/kernel/builder.sh b/pkgs/os-specific/linux/kernel/builder.sh
index 07eb4edded4..f683498417d 100644
--- a/pkgs/os-specific/linux/kernel/builder.sh
+++ b/pkgs/os-specific/linux/kernel/builder.sh
@@ -1,7 +1,7 @@
 source $stdenv/setup
 
 
-makeFlags="ARCH=$arch"
+makeFlags="ARCH=$arch SHELL=/bin/sh"
 
 
 configurePhase() {
diff --git a/pkgs/os-specific/linux/kernel/generate-config.pl b/pkgs/os-specific/linux/kernel/generate-config.pl
index 56320ce882f..e8349db8ec8 100644
--- a/pkgs/os-specific/linux/kernel/generate-config.pl
+++ b/pkgs/os-specific/linux/kernel/generate-config.pl
@@ -128,7 +128,9 @@ while (<CONFIG>) {
 close CONFIG;
 
 foreach my $name (sort (keys %answers)) {
-    my $f = $requiredAnswers{$name} ? sub { die @_; } : sub { warn @_; };
+    my $f = $requiredAnswers{$name} && $ENV{'ignoreConfigErrors'} ne "1"
+        ? sub { die @_; } : sub { warn @_; };
+    my $f = sub { warn @_; };
     &$f("unused option: $name\n") unless defined $config{$name};
     &$f("option not set correctly: $name\n")
         if $config{$name} && $config{$name} ne $answers{$name};
diff --git a/pkgs/os-specific/linux/kernel/generic.nix b/pkgs/os-specific/linux/kernel/generic.nix
index 85fd91ca1bb..b4fca451142 100644
--- a/pkgs/os-specific/linux/kernel/generic.nix
+++ b/pkgs/os-specific/linux/kernel/generic.nix
@@ -66,6 +66,9 @@ stdenv.mkDerivation {
         map ({extraConfig ? "", ...}: extraConfig) kernelPatches;
     in lib.concatStringsSep "\n" ([config] ++ configFromPatches);
 
+  # For UML, just ignore all options that don't apply (I'm lazy).
+  ignoreConfigErrors = userModeLinux;
+
   buildInputs = [ perl mktemp ];
   
   arch =