Cleaned up serial handling, make sure all config is in the block

src/idmslinux_installer/util/sysgrub.py

@@ -75,18 +75,6 @@ class SysGrub:
                     # Rebuild the line
                     line = 'GRUB_PRELOAD_MODULES="' + ' '.join(modules) + '"\n'
 
-                # Check if this is the GRUB_CMDLINE_LINUX line
-                matches = re.match(r'^\s*GRUB_CMDLINE_LINUX="(?P<cmdline>.*)"', line)
-                if matches:
-                    # If we can split it into a list
-                    options = matches.group('cmdline').split()
-                    # If we're dealing with a serial console add options
-                    if is_serial:
-                        options.append('console=ttyS%s,%sn8' % (is_serial['unit'], is_serial['speed']))
-
-                    # Rebuild the line
-                    line = 'GRUB_CMDLINE_LINUX="' + ' '.join(options) + '"\n'
-
                 # Write out line
                 conf_file_new.write(line)
 
@@ -97,6 +85,8 @@ class SysGrub:
                 conf_file_new.write('GRUB_TERMINAL_OUTPUT=serial\n')
                 conf_file_new.write('GRUB_SERIAL_COMMAND="serial --unit=%s --speed=%s"\n' %
                                     (is_serial['unit'], is_serial['speed']))
+                conf_file_new.write('GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX console=ttyS%s,%s"\n' %
+                                    (is_serial['unit'], is_serial['speed']))
                 conf_file_new.write('# END - Serial Console\n')
 
             # Close files