x86: memtest bootparam

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e50e38e..a0d7406 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -382,6 +382,35 @@
 
 endif
 
+config MEMTEST_BOOTPARAM
+	bool "Memtest boot parameter"
+	depends on X86_64
+	default y
+	help
+	  This option adds a kernel parameter 'memtest', which allows memtest
+	  to be disabled at boot.  If this option is selected, memtest
+	  functionality can be disabled with memtest=0 on the kernel
+	  command line.  The purpose of this option is to allow a single
+	  kernel image to be distributed with memtest built in, but not
+	  necessarily enabled.
+
+	  If you are unsure how to answer this question, answer Y.
+
+config MEMTEST_BOOTPARAM_VALUE
+	int "Memtest boot parameter default value (0-4)"
+	depends on MEMTEST_BOOTPARAM
+	range 0 4
+	default 0
+	help
+	  This option sets the default value for the kernel parameter
+	  'memtest', which allows memtest to be disabled at boot.  If this
+	  option is set to 0 (zero), the memtest kernel parameter will
+	  default to 0, disabling memtest at bootup.  If this option is
+	  set to 4, the memtest kernel parameter will default to 4,
+	  enabling memtest at bootup, and use that as pattern number.
+
+	  If you are unsure how to answer this question, answer 0.
+
 config ACPI_SRAT
 	def_bool y
 	depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)