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.
(http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.0/1806.html)

Dan Aloni created the patch set for the above implementation.
(http://www.uwsg.iu.edu/hypermail/linux/kernel/0707.1/1053.html)

And I updated it for multi architectures and memory models.
(http://lists.infradead.org/pipermail/kexec/2007-August/000479.html)

Signed-off-by: Dan Aloni <da-x@monatomic.org>
Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 31 insertions, 1 deletions

diff --git a/arch/ia64/kernel/machine_kexec.c b/arch/ia64/kernel/machine_kexec.c
index 58e943a5d95c..40f9c3e19220 100644
--- a/arch/ia64/kernel/machine_kexec.c
+++ b/arch/ia64/kernel/machine_kexec.c
@@ -15,6 +15,8 @@
 #include <linux/cpu.h>
 #include <linux/irq.h>
 #include <linux/efi.h>
+#include <linux/numa.h>
+#include <linux/mmzone.h>
 #include <asm/mmu_context.h>
 #include <asm/setup.h>
 #include <asm/delay.h>
@@ -121,3 +123,31 @@ void machine_kexec(struct kimage *image)
         unw_init_running(ia64_machine_kexec, image);
         for(;;);
 }
+
+void arch_crash_save_vmcoreinfo(void)
+{
+#ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE
+        SYMBOL(pgdat_list);
+        LENGTH(pgdat_list, MAX_NUMNODES);
+
+        SYMBOL(node_memblk);
+        LENGTH(node_memblk, NR_NODE_MEMBLKS);
+        SIZE(node_memblk_s);
+        OFFSET(node_memblk_s, start_paddr);
+        OFFSET(node_memblk_s, size);
+#endif
+#ifdef CONFIG_PGTABLE_3
+        CONFIG(PGTABLE_3);
+#elif  CONFIG_PGTABLE_4
+        CONFIG(PGTABLE_4);
+#endif
+}
+
+unsigned long paddr_vmcoreinfo_note(void)
+{
+        unsigned long vaddr, paddr;
+        vaddr = (unsigned long)(char *)&vmcoreinfo_note;
+        asm volatile ("tpa %0 = %1" : "=r"(paddr) : "r"(vaddr) : "memory");
+        return paddr;
+}
+
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 5628067a74d2..0b567398f38e 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -48,7 +48,7 @@ struct early_node_data {
 static struct early_node_data mem_data[MAX_NUMNODES] __initdata;
 static nodemask_t memory_less_mask __initdata;
 
-static pg_data_t *pgdat_list[MAX_NUMNODES];
+pg_data_t *pgdat_list[MAX_NUMNODES];
 
 /*
  * To prevent cache aliasing effects, align per-node structures so that they