[PATCH] kdump: x86_64: add elfcorehdr command line option

- elfcorehdr= specifies the location of elf core header stored by the
  crashed kernel.  This command line option will be passed by the kexec-tools
  to capture kernel.

Changes in this version :

- Added more comments in kernel-parameters.txt and in code.

Signed-off-by: Murali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 12b7d93..dd0bfc2 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -475,10 +475,11 @@ running once the system is up.
                        See Documentation/block/as-iosched.txt and
                        Documentation/block/deadline-iosched.txt for details.
 
-       elfcorehdr=     [IA-32]
+       elfcorehdr=     [IA-32, X86_64]
                        Specifies physical address of start of kernel core
-                       image elf header.
-                       See Documentation/kdump.txt for details.
+                       image elf header. Generally kexec loader will
+                       pass this option to capture kernel.
+                       See Documentation/kdump/kdump.txt for details.
 
        enforcing       [SELINUX] Set initial enforcing status.
                        Format: {"0" | "1"}

diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index 27c956d..f685637 100644 (file)
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -898,7 +898,7 @@ static void __init parse_cmdline_early (char ** cmdline_p)
                        }
                }
 #endif
-#ifdef CONFIG_CRASH_DUMP
+#ifdef CONFIG_PROC_VMCORE
                /* elfcorehdr= specifies the location of elf core header
                 * stored by the crashed kernel.
                 */

diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index ff9620b..a0e0c9c 100644 (file)
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -35,6 +35,7 @@
 #include <asm/processor.h>
 #include <linux/console.h>
 #include <linux/seq_file.h>
+#include <linux/crash_dump.h>
 #include <linux/root_dev.h>
 #include <linux/pci.h>
 #include <linux/acpi.h>
@@ -418,6 +419,14 @@ static __init void parse_cmdline_early (char ** cmdline_p)
                }
 #endif
 
+#ifdef CONFIG_PROC_VMCORE
+               /* elfcorehdr= specifies the location of elf core header
+                * stored by the crashed kernel. This option will be passed
+                * by kexec loader to the capture kernel.
+                */
+               else if(!memcmp(from, "elfcorehdr=", 11))
+                       elfcorehdr_addr = memparse(from+11, &from);
+#endif
        next_char:
                c = *(from++);
                if (!c)