Add the 'mitigations' check

The default value for the 'mitigations' option is 'auto'.

So this option should be enabled ('is not off') or not set at all.

kconfig_hardened_check/__init__.py

@@ -15,7 +15,6 @@
 #
 #    Mitigations of CPU vulnerabilities:
 #       Аrch-independent:
-#           mitigations=auto,nosmt (nosmt is slow)
 #       X86:
 #           spec_store_bypass_disable=on
 #           l1tf=full,force
@@ -736,6 +735,8 @@ def add_cmdline_checks(l, arch):
     l += [CmdlineCheck('self_protection', 'defconfig', 'nopti', 'is not set')]
     l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v1', 'is not set')]
     l += [CmdlineCheck('self_protection', 'defconfig', 'nospectre_v2', 'is not set')]
+    l += [OR(CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not off'),
+             CmdlineCheck('self_protection', 'defconfig', 'mitigations', 'is not set'))]
     if arch == 'ARM64':
         l += [OR(CmdlineCheck('self_protection', 'defconfig', 'rodata', 'full'),
                  AND(KconfigCheck('self_protection', 'defconfig', 'RODATA_FULL_DEFAULT_ENABLED', 'y'),
@@ -950,6 +951,9 @@ def normalize_cmdline_options(option, value):
     if option == 'debugfs':
         # See debugfs_kernel() in fs/debugfs/inode.c
         return value
+    if option == 'mitigations':
+        # See mitigations_parse_cmdline() in linux/kernel/cpu.c
+        return value
 
     # Implement a limited part of the kstrtobool() logic
     if value in ('1', 'on', 'On', 'ON', 'y', 'Y', 'yes', 'Yes', 'YES'):