[PATCH] i386/x86-64: Improve Kconfig description of CRASH_DUMP

Improve Kconfig description of CONFIG_CRASH_DUMP. Previously
it was too brief to be useful.

Cc: vgoyal@in.ibm.com
Cc: ebiederm@xmission.com
Signed-off-by: Andi Kleen <ak@suse.de>

diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index c134a545b37eaeaa3f67435a0366b382ec89e3d9..e34a4dbd6b920566d66a0446a63bace03b029f20 100644 (file)
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -761,6 +761,13 @@ config CRASH_DUMP
        depends on HIGHMEM
        help
          Generate crash dump after being started by kexec.
+          This should be normally only set in special crash dump kernels
+         which are loaded in the main kernel with kexec-tools into
+         a specially reserved region and then later executed after
+         a crash by kdump/kexec. The crash dump kernel must be compiled
+          to a memory address not used by the main kernel or BIOS using
+          PHYSICAL_START.
+         For more details see Documentation/kdump/kdump.txt
 
 config PHYSICAL_START
        hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)

diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 6cd4878625f1af0bdf30ec5435054e6d1ceb47d4..927b392a4aa00a753583b8915847bc4809403ed0 100644 (file)
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -488,7 +488,14 @@ config CRASH_DUMP
        bool "kernel crash dumps (EXPERIMENTAL)"
        depends on EXPERIMENTAL
        help
-               Generate crash dump after being started by kexec.
+          Generate crash dump after being started by kexec.
+          This should be normally only set in special crash dump kernels
+          which are loaded in the main kernel with kexec-tools into
+          a specially reserved region and then later executed after
+          a crash by kdump/kexec. The crash dump kernel must be compiled
+         to a memory address not used by the main kernel or BIOS using
+         PHYSICAL_START.
+          For more details see Documentation/kdump/kdump.txt
 
 config PHYSICAL_START
        hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)