diff --git a/tools/testing/ktest/config-bisect.pl b/tools/testing/ktest/config-bisect.pl
new file mode 100755
index 000000000000..37cd796efa2b
--- /dev/null
+++ b/tools/testing/ktest/config-bisect.pl
@@ -0,0 +1,763 @@
+#!/usr/bin/perl -w
+#
+# Copyright 2015 - Steven Rostedt, Red Hat Inc.
+# Copyright 2017 - Steven Rostedt, VMware, Inc.
+#
+# Licensed under the terms of the GNU GPL License version 2
+#
+
+# usage:
+#  config-bisect.pl [options] good-config bad-config [good|bad]
+#
+
+# Compares a good config to a bad config, then takes half of the diffs
+# and produces a config that is somewhere between the good config and
+# the bad config. That is, the resulting config will start with the
+# good config and will try to make half of the differences of between
+# the good and bad configs match the bad config. It tries because of
+# dependencies between the two configs it may not be able to change
+# exactly half of the configs that are different between the two config
+# files.
+
+# Here's a normal way to use it:
+#
+#  $ cd /path/to/linux/kernel
+#  $ config-bisect.pl /path/to/good/config /path/to/bad/config
+
+# This will now pull in good config (blowing away .config in that directory
+# so do not make that be one of the good or bad configs), and then
+# build the config with "make oldconfig" to make sure it matches the
+# current kernel. It will then store the configs in that result for
+# the good config. It does the same for the bad config as well.
+# The algorithm will run, merging half of the differences between
+# the two configs and building them with "make oldconfig" to make sure
+# the result changes (dependencies may reset changes the tool had made).
+# It then copies the result of its good config to /path/to/good/config.tmp
+# and the bad config to /path/to/bad/config.tmp (just appends ".tmp" to the
+# files passed in). And the ".config" that you should test will be in
+# directory
+
+# After the first run, determine if the result is good or bad then
+# run the same command appending the result
+
+# For good results:
+#  $ config-bisect.pl /path/to/good/config /path/to/bad/config good
+
+# For bad results:
+#  $ config-bisect.pl /path/to/good/config /path/to/bad/config bad
+
+# Do not change the good-config or bad-config, config-bisect.pl will
+# copy the good-config to a temp file with the same name as good-config
+# but with a ".tmp" after it. It will do the same with the bad-config.
+
+# If "good" or "bad" is not stated at the end, it will copy the good and
+# bad configs to the .tmp versions. If a .tmp version already exists, it will
+# warn before writing over them. If the last config is labeled "good", then
+# it will copy it to the good .tmp version. If the last config is labeled
+# "bad", it will copy it to the bad .tmp version. It will continue this until
+# it can not merge the two any more without the result being equal to either
+# the good or bad .tmp configs.
+
+my $start = 0;
+my $val = "";
+
+my $pwd = `pwd`;
+chomp $pwd;
+my $tree = $pwd;
+my $build;
+
+my $output_config;
+
+sub usage {
+    print << "EOF"
+
+usage: config-bisect.pl [-l linux-tree][-b build-dir] good-config bad-config [good|bad]
+  -l [optional] define location of linux-tree (default is current directory)
+  -b [optional] define location to build (O=build-dir) (default is linux-tree)
+  good-config the config that is considered good
+  bad-config the config that does not work
+  "good" add this if the last run produced a good config
+  "bad" add this if the last run produced a bad config
+  If "good" or "bad" is not specified, then it is the start of a new bisect
+
+  Note, each run will create copy of good and bad configs with ".tmp" appended.
+
+EOF
+;
+
+    exit(-1);
+}
+
+sub doprint {
+    print @_;
+}
+
+sub dodie {
+    doprint "CRITICAL FAILURE... ", @_, "\n";
+
+    die @_, "\n";
+}
+
+sub expand_path {
+    my ($file) = @_;
+
+    if ($file =~ m,^/,) {
+	return $file;
+    }
+    return "$pwd/$file";
+}
+
+sub read_prompt {
+    my ($cancel, $prompt) = @_;
+
+    my $ans;
+
+    for (;;) {
+	if ($cancel) {
+	    print "$prompt [y/n/C] ";
+	} else {
+	    print "$prompt [y/N] ";
+	}
+	$ans = <STDIN>;
+	chomp $ans;
+	if ($ans =~ /^\s*$/) {
+	    if ($cancel) {
+		$ans = "c";
+	    } else {
+		$ans = "n";
+	    }
+	}
+	last if ($ans =~ /^y$/i || $ans =~ /^n$/i);
+	if ($cancel) {
+	    last if ($ans =~ /^c$/i);
+	    print "Please answer either 'y', 'n' or 'c'.\n";
+	} else {
+	    print "Please answer either 'y' or 'n'.\n";
+	}
+    }
+    if ($ans =~ /^c/i) {
+	exit;
+    }
+    if ($ans !~ /^y$/i) {
+	return 0;
+    }
+    return 1;
+}
+
+sub read_yn {
+    my ($prompt) = @_;
+
+    return read_prompt 0, $prompt;
+}
+
+sub read_ync {
+    my ($prompt) = @_;
+
+    return read_prompt 1, $prompt;
+}
+
+sub run_command {
+    my ($command, $redirect) = @_;
+    my $start_time;
+    my $end_time;
+    my $dord = 0;
+    my $pid;
+
+    $start_time = time;
+
+    doprint("$command ... ");
+
+    $pid = open(CMD, "$command 2>&1 |") or
+	dodie "unable to exec $command";
+
+    if (defined($redirect)) {
+	open (RD, ">$redirect") or
+	    dodie "failed to write to redirect $redirect";
+	$dord = 1;
+    }
+
+    while (<CMD>) {
+	print RD  if ($dord);
+    }
+
+    waitpid($pid, 0);
+    my $failed = $?;
+
+    close(CMD);
+    close(RD)  if ($dord);
+
+    $end_time = time;
+    my $delta = $end_time - $start_time;
+
+    if ($delta == 1) {
+	doprint "[1 second] ";
+    } else {
+	doprint "[$delta seconds] ";
+    }
+
+    if ($failed) {
+	doprint "FAILED!\n";
+    } else {
+	doprint "SUCCESS\n";
+    }
+
+    return !$failed;
+}
+
+###### CONFIG BISECT ######
+
+# config_ignore holds the configs that were set (or unset) for
+# a good config and we will ignore these configs for the rest
+# of a config bisect. These configs stay as they were.
+my %config_ignore;
+
+# config_set holds what all configs were set as.
+my %config_set;
+
+# config_off holds the set of configs that the bad config had disabled.
+# We need to record them and set them in the .config when running
+# olddefconfig, because olddefconfig keeps the defaults.
+my %config_off;
+
+# config_off_tmp holds a set of configs to turn off for now
+my @config_off_tmp;
+
+# config_list is the set of configs that are being tested
+my %config_list;
+my %null_config;
+
+my %dependency;
+
+my $make;
+
+sub make_oldconfig {
+
+    if (!run_command "$make olddefconfig") {
+	# Perhaps olddefconfig doesn't exist in this version of the kernel
+	# try oldnoconfig
+	doprint "olddefconfig failed, trying make oldnoconfig\n";
+	if (!run_command "$make oldnoconfig") {
+	    doprint "oldnoconfig failed, trying yes '' | make oldconfig\n";
+	    # try a yes '' | oldconfig
+	    run_command "yes '' | $make oldconfig" or
+		dodie "failed make config oldconfig";
+	}
+    }
+}
+
+sub assign_configs {
+    my ($hash, $config) = @_;
+
+    doprint "Reading configs from $config\n";
+
+    open (IN, $config)
+	or dodie "Failed to read $config";
+
+    while (<IN>) {
+	chomp;
+	if (/^((CONFIG\S*)=.*)/) {
+	    ${$hash}{$2} = $1;
+	} elsif (/^(# (CONFIG\S*) is not set)/) {
+	    ${$hash}{$2} = $1;
+	}
+    }
+
+    close(IN);
+}
+
+sub process_config_ignore {
+    my ($config) = @_;
+
+    assign_configs \%config_ignore, $config;
+}
+
+sub get_dependencies {
+    my ($config) = @_;
+
+    my $arr = $dependency{$config};
+    if (!defined($arr)) {
+	return ();
+    }
+
+    my @deps = @{$arr};
+
+    foreach my $dep (@{$arr}) {
+	print "ADD DEP $dep\n";
+	@deps = (@deps, get_dependencies $dep);
+    }
+
+    return @deps;
+}
+
+sub save_config {
+    my ($pc, $file) = @_;
+
+    my %configs = %{$pc};
+
+    doprint "Saving configs into $file\n";
+
+    open(OUT, ">$file") or dodie "Can not write to $file";
+
+    foreach my $config (keys %configs) {
+	print OUT "$configs{$config}\n";
+    }
+    close(OUT);
+}
+
+sub create_config {
+    my ($name, $pc) = @_;
+
+    doprint "Creating old config from $name configs\n";
+
+    save_config $pc, $output_config;
+
+    make_oldconfig;
+}
+
+# compare two config hashes, and return configs with different vals.
+# It returns B's config values, but you can use A to see what A was.
+sub diff_config_vals {
+    my ($pa, $pb) = @_;
+
+    # crappy Perl way to pass in hashes.
+    my %a = %{$pa};
+    my %b = %{$pb};
+
+    my %ret;
+
+    foreach my $item (keys %a) {
+	if (defined($b{$item}) && $b{$item} ne $a{$item}) {
+	    $ret{$item} = $b{$item};
+	}
+    }
+
+    return %ret;
+}
+
+# compare two config hashes and return the configs in B but not A
+sub diff_configs {
+    my ($pa, $pb) = @_;
+
+    my %ret;
+
+    # crappy Perl way to pass in hashes.
+    my %a = %{$pa};
+    my %b = %{$pb};
+
+    foreach my $item (keys %b) {
+	if (!defined($a{$item})) {
+	    $ret{$item} = $b{$item};
+	}
+    }
+
+    return %ret;
+}
+
+# return if two configs are equal or not
+# 0 is equal +1 b has something a does not
+# +1 if a and b have a different item.
+# -1 if a has something b does not
+sub compare_configs {
+    my ($pa, $pb) = @_;
+
+    my %ret;
+
+    # crappy Perl way to pass in hashes.
+    my %a = %{$pa};
+    my %b = %{$pb};
+
+    foreach my $item (keys %b) {
+	if (!defined($a{$item})) {
+	    return 1;
+	}
+	if ($a{$item} ne $b{$item}) {
+	    return 1;
+	}
+    }
+
+    foreach my $item (keys %a) {
+	if (!defined($b{$item})) {
+	    return -1;
+	}
+    }
+
+    return 0;
+}
+
+sub process_failed {
+    my ($config) = @_;
+
+    doprint "\n\n***************************************\n";
+    doprint "Found bad config: $config\n";
+    doprint "***************************************\n\n";
+}
+
+sub process_new_config {
+    my ($tc, $nc, $gc, $bc) = @_;
+
+    my %tmp_config = %{$tc};
+    my %good_configs = %{$gc};
+    my %bad_configs = %{$bc};
+
+    my %new_configs;
+
+    my $runtest = 1;
+    my $ret;
+
+    create_config "tmp_configs", \%tmp_config;
+    assign_configs \%new_configs, $output_config;
+
+    $ret = compare_configs \%new_configs, \%bad_configs;
+    if (!$ret) {
+	doprint "New config equals bad config, try next test\n";
+	$runtest = 0;
+    }
+
+    if ($runtest) {
+	$ret = compare_configs \%new_configs, \%good_configs;
+	if (!$ret) {
+	    doprint "New config equals good config, try next test\n";
+	    $runtest = 0;
+	}
+    }
+
+    %{$nc} = %new_configs;
+
+    return $runtest;
+}
+
+sub convert_config {
+    my ($config) = @_;
+
+    if ($config =~ /^# (.*) is not set/) {
+	$config = "$1=n";
+    }
+
+    $config =~ s/^CONFIG_//;
+    return $config;
+}
+
+sub print_config {
+    my ($sym, $config) = @_;
+
+    $config = convert_config $config;
+    doprint "$sym$config\n";
+}
+
+sub print_config_compare {
+    my ($good_config, $bad_config) = @_;
+
+    $good_config = convert_config $good_config;
+    $bad_config = convert_config $bad_config;
+
+    my $good_value = $good_config;
+    my $bad_value = $bad_config;
+    $good_value =~ s/(.*)=//;
+    my $config = $1;
+
+    $bad_value =~ s/.*=//;
+
+    doprint " $config $good_value -> $bad_value\n";
+}
+
+# Pass in:
+# $phalf: half of the configs names you want to add
+# $oconfigs: The orginial configs to start with
+# $sconfigs: The source to update $oconfigs with (from $phalf)
+# $which: The name of which half that is updating (top / bottom)
+# $type: The name of the source type (good / bad)
+sub make_half {
+    my ($phalf, $oconfigs, $sconfigs, $which, $type) = @_;
+
+    my @half = @{$phalf};
+    my %orig_configs = %{$oconfigs};
+    my %source_configs = %{$sconfigs};
+
+    my %tmp_config = %orig_configs;
+
+    doprint "Settings bisect with $which half of $type configs:\n";
+    foreach my $item (@half) {
+	doprint "Updating $item to $source_configs{$item}\n";
+	$tmp_config{$item} = $source_configs{$item};
+    }
+
+    return %tmp_config;
+}
+
+sub run_config_bisect {
+    my ($pgood, $pbad) = @_;
+
+    my %good_configs = %{$pgood};
+    my %bad_configs = %{$pbad};
+
+    my %diff_configs = diff_config_vals \%good_configs, \%bad_configs;
+    my %b_configs = diff_configs \%good_configs, \%bad_configs;
+    my %g_configs = diff_configs \%bad_configs, \%good_configs;
+
+    # diff_arr is what is in both good and bad but are different (y->n)
+    my @diff_arr = keys %diff_configs;
+    my $len_diff = $#diff_arr + 1;
+
+    # b_arr is what is in bad but not in good (has depends)
+    my @b_arr = keys %b_configs;
+    my $len_b = $#b_arr + 1;
+
+    # g_arr is what is in good but not in bad
+    my @g_arr = keys %g_configs;
+    my $len_g = $#g_arr + 1;
+
+    my $runtest = 0;
+    my %new_configs;
+    my $ret;
+
+    # Look at the configs that are different between good and bad.
+    # This does not include those that depend on other configs
+    #  (configs depending on other configs that are not set would
+    #   not show up even as a "# CONFIG_FOO is not set"
+
+
+    doprint "# of configs to check:             $len_diff\n";
+    doprint "# of configs showing only in good: $len_g\n";
+    doprint "# of configs showing only in bad:  $len_b\n";
+
+    if ($len_diff > 0) {
+	# Now test for different values
+
+	doprint "Configs left to check:\n";
+	doprint "  Good Config\t\t\tBad Config\n";
+	doprint "  -----------\t\t\t----------\n";
+	foreach my $item (@diff_arr) {
+	    doprint "  $good_configs{$item}\t$bad_configs{$item}\n";
+	}
+
+	my $half = int($#diff_arr / 2);
+	my @tophalf = @diff_arr[0 .. $half];
+
+	doprint "Set tmp config to be good config with some bad config values\n";
+
+	my %tmp_config = make_half \@tophalf, \%good_configs,
+	    \%bad_configs, "top", "bad";
+
+	$runtest = process_new_config \%tmp_config, \%new_configs,
+			    \%good_configs, \%bad_configs;
+
+	if (!$runtest) {
+	    doprint "Set tmp config to be bad config with some good config values\n";
+
+	    my %tmp_config = make_half \@tophalf, \%bad_configs,
+		\%good_configs, "top", "good";
+
+	    $runtest = process_new_config \%tmp_config, \%new_configs,
+		\%good_configs, \%bad_configs;
+	}
+    }
+
+    if (!$runtest && $len_diff > 0) {
+	# do the same thing, but this time with bottom half
+
+	my $half = int($#diff_arr / 2);
+	my @bottomhalf = @diff_arr[$half+1 .. $#diff_arr];
+
+	doprint "Set tmp config to be good config with some bad config values\n";
+
+	my %tmp_config = make_half \@bottomhalf, \%good_configs,
+	    \%bad_configs, "bottom", "bad";
+
+	$runtest = process_new_config \%tmp_config, \%new_configs,
+			    \%good_configs, \%bad_configs;
+
+	if (!$runtest) {
+	    doprint "Set tmp config to be bad config with some good config values\n";
+
+	    my %tmp_config = make_half \@bottomhalf, \%bad_configs,
+		\%good_configs, "bottom", "good";
+
+	    $runtest = process_new_config \%tmp_config, \%new_configs,
+		\%good_configs, \%bad_configs;
+	}
+    }
+
+    if ($runtest) {
+	make_oldconfig;
+	doprint "READY TO TEST .config IN $build\n";
+	return 0;
+    }
+
+    doprint "\n%%%%%%%% FAILED TO FIND SINGLE BAD CONFIG %%%%%%%%\n";
+    doprint "Hmm, can't make any more changes without making good == bad?\n";
+    doprint "Difference between good (+) and bad (-)\n";
+
+    foreach my $item (keys %bad_configs) {
+	if (!defined($good_configs{$item})) {
+	    print_config "-", $bad_configs{$item};
+	}
+    }
+
+    foreach my $item (keys %good_configs) {
+	next if (!defined($bad_configs{$item}));
+	if ($good_configs{$item} ne $bad_configs{$item}) {
+	    print_config_compare $good_configs{$item}, $bad_configs{$item};
+	}
+    }
+
+    foreach my $item (keys %good_configs) {
+	if (!defined($bad_configs{$item})) {
+	    print_config "+", $good_configs{$item};
+	}
+    }
+    return -1;
+}
+
+sub config_bisect {
+    my ($good_config, $bad_config) = @_;
+    my $ret;
+
+    my %good_configs;
+    my %bad_configs;
+    my %tmp_configs;
+
+    doprint "Run good configs through make oldconfig\n";
+    assign_configs \%tmp_configs, $good_config;
+    create_config "$good_config", \%tmp_configs;
+    assign_configs \%good_configs, $output_config;
+
+    doprint "Run bad configs through make oldconfig\n";
+    assign_configs \%tmp_configs, $bad_config;
+    create_config "$bad_config", \%tmp_configs;
+    assign_configs \%bad_configs, $output_config;
+
+    save_config \%good_configs, $good_config;
+    save_config \%bad_configs, $bad_config;
+
+    return run_config_bisect \%good_configs, \%bad_configs;
+}
+
+while ($#ARGV >= 0) {
+    if ($ARGV[0] !~ m/^-/) {
+	last;
+    }
+    my $opt = shift @ARGV;
+
+    if ($opt eq "-b") {
+	$val = shift @ARGV;
+	if (!defined($val)) {
+	    die "-b requires value\n";
+	}
+	$build = $val;
+    }
+
+    elsif ($opt eq "-l") {
+	$val = shift @ARGV;
+	if (!defined($val)) {
+	    die "-l requires value\n";
+	}
+	$tree = $val;
+    }
+
+    elsif ($opt eq "-h") {
+	usage;
+    }
+
+    else {
+	die "Unknow option $opt\n";
+    }
+}
+
+$build = $tree if (!defined($build));
+
+$tree = expand_path $tree;
+$build = expand_path $build;
+
+if ( ! -d $tree ) {
+    die "$tree not a directory\n";
+}
+
+if ( ! -d $build ) {
+    die "$build not a directory\n";
+}
+
+usage if $#ARGV < 1;
+
+if ($#ARGV == 1) {
+    $start = 1;
+} elsif ($#ARGV == 2) {
+    $val = $ARGV[2];
+    if ($val ne "good" && $val ne "bad") {
+	die "Unknown command '$val', bust be either \"good\" or \"bad\"\n";
+    }
+} else {
+    usage;
+}
+
+my $good_start = expand_path $ARGV[0];
+my $bad_start = expand_path $ARGV[1];
+
+my $good = "$good_start.tmp";
+my $bad = "$bad_start.tmp";
+
+$make = "make";
+
+if ($build ne $tree) {
+    $make = "make O=$build"
+}
+
+$output_config = "$build/.config";
+
+if ($start) {
+    if ( ! -f $good_start ) {
+	die "$good_start not found\n";
+    }
+    if ( ! -f $bad_start ) {
+	die "$bad_start not found\n";
+    }
+    if ( -f $good || -f $bad ) {
+	my $p = "";
+
+	if ( -f $good ) {
+	    $p = "$good exists\n";
+	}
+
+	if ( -f $bad ) {
+	    $p = "$p$bad exists\n";
+	}
+
+	if (!read_yn "${p}Overwrite and start new bisect anyway?") {
+	    exit (-1);
+	}
+    }
+    run_command "cp $good_start $good" or die "failed to copy to $good\n";
+    run_command "cp $bad_start $bad" or die "faield to copy to $bad\n";
+} else {
+    if ( ! -f $good ) {
+	die "Can not find file $good\n";
+    }
+    if ( ! -f $bad ) {
+	die "Can not find file $bad\n";
+    }
+    if ($val eq "good") {
+	run_command "cp $output_config $good" or die "failed to copy $config to $good\n";
+    } elsif ($val eq "bad") {
+	run_command "cp $output_config $bad" or die "failed to copy $config to $bad\n";
+    }
+}
+
+chdir $tree || die "can't change directory to $tree";
+
+my $ret = config_bisect $good, $bad;
+
+if (!$ret) {
+    exit(0);
+}
+
+if ($ret > 0) {
+    doprint "Cleaning temp files\n";
+    run_command "rm $good";
+    run_command "rm $bad";
+    exit(1);
+} else {
+    doprint "See good and bad configs for details:\n";
+    doprint "good: $good\n";
+    doprint "bad:  $bad\n";
+    doprint "%%%%%%%% FAILED TO FIND SINGLE BAD CONFIG %%%%%%%%\n";
+}
+exit(2);