kest.pl: Fix grub2 menu handling for rebooting

grub2 has submenus where to use grub-reboot, it requires:

  grub-reboot X>Y

where X is the main index and Y is the submenu. Thus if you have:

menuentry 'Debian GNU/Linux' --class debian --class gnu-linux ...
	[...]
}
submenu 'Advanced options for Debian GNU/Linux' $menuentry_id_option ...
        menuentry 'Debian GNU/Linux, with Linux 6.0.0-4-amd64' --class debian --class gnu-linux ...
                [...]
        }
        menuentry 'Debian GNU/Linux, with Linux 6.0.0-4-amd64 (recovery mode)' --class debian --class gnu-linux ...
		[...]
        }
        menuentry 'Debian GNU/Linux, with Linux test' --class debian --class gnu-linux ...
                [...]
        }

And wanted to boot to the "Linux test" kernel, you need to run:

 # grub-reboot 1>2

As 1 is the second top menu (the submenu) and 2 is the third of the sub
menu entries.

Have the grub.cfg parsing for grub2 handle such cases.

Cc: stable@vger.kernel.org
Fixes: a15ba913 ("ktest: Add support for grub2")
Reviewed-by: John 'Warthog9' Hawley (VMware) <warthog9@eaglescrag.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

tools/testing/ktest/ktest.pl

@@ -1963,7 +1963,7 @@ sub run_scp_mod {
 
 sub _get_grub_index {
 
-    my ($command, $target, $skip) = @_;
+    my ($command, $target, $skip, $submenu) = @_;
 
     return if (defined($grub_number) && defined($last_grub_menu) &&
 	$last_grub_menu eq $grub_menu && defined($last_machine) &&
@@ -1980,11 +1980,16 @@ sub _get_grub_index {
 
     my $found = 0;
 
+    my $submenu_number = 0;
+
     while (<IN>) {
 	if (/$target/) {
 	    $grub_number++;
 	    $found = 1;
 	    last;
+	} elsif (defined($submenu) && /$submenu/) {
+		$submenu_number++;
+		$grub_number = -1;
 	} elsif (/$skip/) {
 	    $grub_number++;
 	}
@@ -1993,6 +1998,9 @@ sub _get_grub_index {
 
     dodie "Could not find '$grub_menu' through $command on $machine"
 	if (!$found);
+    if ($submenu_number > 0) {
+	$grub_number = "$submenu_number>$grub_number";
+    }
     doprint "$grub_number\n";
     $last_grub_menu = $grub_menu;
     $last_machine = $machine;
@@ -2003,6 +2011,7 @@ sub get_grub_index {
     my $command;
     my $target;
     my $skip;
+    my $submenu;
     my $grub_menu_qt;
 
     if ($reboot_type !~ /^grub/) {
@@ -2017,8 +2026,9 @@ sub get_grub_index {
 	$skip = '^\s*title\s';
     } elsif ($reboot_type eq "grub2") {
 	$command = "cat $grub_file";
-	$target = '^menuentry.*' . $grub_menu_qt;
-	$skip = '^menuentry\s|^submenu\s';
+	$target = '^\s*menuentry.*' . $grub_menu_qt;
+	$skip = '^\s*menuentry';
+	$submenu = '^\s*submenu\s';
     } elsif ($reboot_type eq "grub2bls") {
 	$command = $grub_bls_get;
 	$target = '^title=.*' . $grub_menu_qt;
@@ -2027,7 +2037,7 @@ sub get_grub_index {
 	return;
     }
 
-    _get_grub_index($command, $target, $skip);
+    _get_grub_index($command, $target, $skip, $submenu);
 }
 
 sub wait_for_input {
@@ -2090,7 +2100,7 @@ sub reboot_to {
     if ($reboot_type eq "grub") {
 	run_ssh "'(echo \"savedefault --default=$grub_number --once\" | grub --batch)'";
     } elsif (($reboot_type eq "grub2") or ($reboot_type eq "grub2bls")) {
-	run_ssh "$grub_reboot $grub_number";
+	run_ssh "$grub_reboot \"'$grub_number'\"";
     } elsif ($reboot_type eq "syslinux") {
 	run_ssh "$syslinux --once \\\"$syslinux_label\\\" $syslinux_path";
     } elsif (defined $reboot_script) {