[PATCH] Kdump: Export crash notes section address through sysfs

o Following patch exports kexec global variable "crash_notes" to user space
  through sysfs as kernel attribute in /sys/kernel.

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 1f064a63f8cf..015fb69ad94d 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -30,6 +30,16 @@ static ssize_t hotplug_seqnum_show(struct subsystem *subsys, char *page)
 KERNEL_ATTR_RO(hotplug_seqnum);
 #endif
 
+#ifdef CONFIG_KEXEC
+#include <asm/kexec.h>
+
+static ssize_t crash_notes_show(struct subsystem *subsys, char *page)
+{
+        return sprintf(page, "%p\n", (void *)crash_notes);
+}
+KERNEL_ATTR_RO(crash_notes);
+#endif
+
 decl_subsys(kernel, NULL, NULL);
 EXPORT_SYMBOL_GPL(kernel_subsys);
 
@@ -37,6 +47,9 @@ static struct attribute * kernel_attrs[] = {
 #ifdef CONFIG_HOTPLUG
         &hotplug_seqnum_attr.attr,
 #endif
+#ifdef CONFIG_KEXEC
+        &crash_notes_attr.attr,
+#endif
         NULL
 };