path: root/kernel/ksysfs.c
diff options
authorKen'ichi Ohmichi <>2007-10-16 23:27:27 -0700
committerLinus Torvalds <>2007-10-17 08:42:54 -0700
commitfd59d231f81cb02870b9cf15f456a897f3669b4e (patch)
tree5713c13bd678774f1ba3c42bfff5008c1812deae /kernel/ksysfs.c
parent0e647c04f665e9b3451a1ebe8252b38ffe0207c8 (diff)
Add vmcoreinfo
This patch set frees the restriction that makedumpfile users should install a vmlinux file (including the debugging information) into each system. makedumpfile command is the dump filtering feature for kdump. It creates a small dumpfile by filtering unnecessary pages for the analysis. To distinguish unnecessary pages, it needs a vmlinux file including the debugging information. These days, the debugging package becomes a huge file, and it is hard to install it into each system. To solve the problem, kdump developers discussed it at lkml and kexec-ml. As the result, we reached the conclusion that necessary information for dump filtering (called "vmcoreinfo") should be embedded into the first kernel file and it should be accessed through /proc/vmcore during the second kernel. ( Dan Aloni created the patch set for the above implementation. ( And I updated it for multi architectures and memory models. ( Signed-off-by: Dan Aloni <> Signed-off-by: Ken'ichi Ohmichi <> Signed-off-by: Bernhard Walle <> Signed-off-by: Daisuke Nishimura <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'kernel/ksysfs.c')
1 files changed, 10 insertions, 0 deletions
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 6046939d0804..38b38f957ef0 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -61,6 +61,15 @@ static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page)
return sprintf(page, "%d\n", !!kexec_crash_image);
+static ssize_t vmcoreinfo_show(struct kset *kset, char *page)
+ return sprintf(page, "%lx %x\n",
+ paddr_vmcoreinfo_note(),
+ vmcoreinfo_max_size);
#endif /* CONFIG_KEXEC */
@@ -96,6 +105,7 @@ static struct attribute * kernel_attrs[] = {
+ &vmcoreinfo_attr.attr,