x86: default corruption check to off, but put parameter default in Kconfig

[linux-2.6-omap-h63xx.git] / arch / x86 / Kconfig

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ed92864d1325c09092f3e8ed4918f26341f23161..7820d447bb8d31f71c40b1347ca94d8cf2a9649f 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1059,6 +1059,36 @@ config HIGHPTE
          low memory.  Setting this option will put user-space page table
          entries in high memory.
 
+config X86_CHECK_BIOS_CORRUPTION
+        bool "Check for low memory corruption"
+       help
+        Periodically check for memory corruption in low memory, which
+        is suspected to be caused by BIOS.  Even when enabled in the
+        configuration, it is disabled at runtime.  Enable it by
+        setting "memory_corruption_check=1" on the kernel command
+        line.  By default it scans the low 64k of memory every 60
+        seconds; see the memory_corruption_check_size and
+        memory_corruption_check_period parameters in
+        Documentation/kernel-parameters.txt to adjust this.
+
+        When enabled with the default parameters, this option has
+        almost no overhead, as it reserves a relatively small amount
+        of memory and scans it infrequently.  It both detects corruption
+        and prevents it from affecting the running system.
+
+        It is, however, intended as a diagnostic tool; if repeatable
+        BIOS-originated corruption always affects the same memory,
+        you can use memmap= to prevent the kernel from using that
+        memory.
+
+config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
+        bool "Set the default setting of memory_corruption_check"
+       depends on X86_CHECK_BIOS_CORRUPTION
+       default y
+       help
+        Set whether the default state of memory_corruption_check is
+        on or off.
+
 config MATH_EMULATION
        bool
        prompt "Math emulation" if X86_32