2 files changed, 44 insertions, 8 deletions

diff --git a/tools/testing/ktest/ktest.pl b/tools/testing/ktest/ktest.pl
index b4f32e73474..7bce412bbdc 100755
--- a/tools/testing/ktest/ktest.pl
+++ b/tools/testing/ktest/ktest.pl
@@ -337,10 +337,17 @@ sub process_variables {
 }
 
 sub set_value {
-    my ($lvalue, $rvalue) = @_;
+    my ($lvalue, $rvalue, $override, $overrides, $name) = @_;
 
     if (defined($opt{$lvalue})) {
-        die "Error: Option $lvalue defined more than once!\n";
+        if (!$override || defined(${$overrides}{$lvalue})) {
+            my $extra = "";
+            if ($override) {
+                $extra = "In the same override section!\n";
+            }
+            die "$name: $.: Option $lvalue defined more than once!\n$extra";
+        }
+        ${$overrides}{$lvalue} = $rvalue;
     }
     if ($rvalue =~ /^\s*$/) {
         delete $opt{$lvalue};
@@ -430,6 +437,9 @@ sub __read_config {
     my $test_case = 0;
     my $if = 0;
     my $if_set = 0;
+    my $override = 0;
+
+    my %overrides;
 
     while (<$in>) {
 
@@ -443,6 +453,7 @@ sub __read_config {
 
             my $old_test_num;
             my $old_repeat;
+            $override = 0;
 
             if ($type eq "TEST_START") {
 
@@ -468,10 +479,20 @@ sub __read_config {
                 $skip = 0;
             }
 
-            if ($rest =~ /\s+ITERATE\s+(\d+)(.*)$/) {
-                $repeat = $1;
-                $rest = $2;
-                $repeat_tests{"$test_num"} = $repeat;
+            if (!$skip) {
+                if ($type eq "TEST_START") {
+                    if ($rest =~ /\s+ITERATE\s+(\d+)(.*)$/) {
+                        $repeat = $1;
+                        $rest = $2;
+                        $repeat_tests{"$test_num"} = $repeat;
+                    }
+                } elsif ($rest =~ /\sOVERRIDE\b(.*)/) {
+                    # DEFAULT only
+                    $rest = $1;
+                    $override = 1;
+                    # Clear previous overrides
+                    %overrides = ();
+                }
             }
 
             if ($rest =~ /\sIF\s+(.*)/) {
@@ -573,10 +594,10 @@ sub __read_config {
             }
 
             if ($default || $lvalue =~ /\[\d+\]$/) {
-                set_value($lvalue, $rvalue);
+                set_value($lvalue, $rvalue, $override, \%overrides, $name);
             } else {
                 my $val = "$lvalue\[$test_num\]";
-                set_value($val, $rvalue);
+                set_value($val, $rvalue, $override, \%overrides, $name);
 
                 if ($repeat > 1) {
                     $repeats{$val} = $repeat;
diff --git a/tools/testing/ktest/sample.conf b/tools/testing/ktest/sample.conf
index ae2a93c732a..0fd3ca30ad0 100644
--- a/tools/testing/ktest/sample.conf
+++ b/tools/testing/ktest/sample.conf
@@ -72,6 +72,21 @@
 # the same option name under the same test or as default
 # ktest will fail to execute, and no tests will run.
 #
+# DEFAULTS OVERRIDE
+#
+# Options defined in the DEFAULTS section can not be duplicated
+# even if they are defined in two different DEFAULT sections.
+# This is done to catch mistakes where an option is added but
+# the previous option was forgotten about and not commented.
+#
+# The OVERRIDE keyword can be added to a section to allow this
+# section to override other DEFAULT sections values that have
+# been defined previously. It will only override options that
+# have been defined before its use. Options defined later
+# in a non override section will still error. The same option
+# can not be defined in the same section even if that section
+# is marked OVERRIDE.
+#
 #
 #
 # Both TEST_START and DEFAULTS sections can also have the IF keyword