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>
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 8c2c7fc..99f2d6f 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -121,6 +121,23 @@
extern void crash_kexec(struct pt_regs *);
int kexec_should_crash(struct task_struct *);
void crash_save_cpu(struct pt_regs *regs, int cpu);
+void crash_save_vmcoreinfo(void);
+void arch_crash_save_vmcoreinfo(void);
+void vmcoreinfo_append_str(const char *fmt, ...);
+unsigned long paddr_vmcoreinfo_note(void);
+
+#define SYMBOL(name) \
+ vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
+#define SIZE(name) \
+ vmcoreinfo_append_str("SIZE(%s)=%d\n", #name, sizeof(struct name))
+#define OFFSET(name, field) \
+ vmcoreinfo_append_str("OFFSET(%s.%s)=%d\n", #name, #field, \
+ &(((struct name *)0)->field))
+#define LENGTH(name, value) \
+ vmcoreinfo_append_str("LENGTH(%s)=%d\n", #name, value)
+#define CONFIG(name) \
+ vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
+
extern struct kimage *kexec_image;
extern struct kimage *kexec_crash_image;
@@ -148,11 +165,20 @@
#define KEXEC_FLAGS (KEXEC_ON_CRASH) /* List of defined/legal kexec flags */
+#define VMCOREINFO_BYTES (4096)
+#define VMCOREINFO_NOTE_NAME "VMCOREINFO"
+#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
+#define VMCOREINFO_NOTE_SIZE (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
+ + VMCOREINFO_NOTE_NAME_BYTES)
+
/* Location of a reserved region to hold the crash kernel.
*/
extern struct resource crashk_res;
typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
extern note_buf_t *crash_notes;
+extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
+extern unsigned int vmcoreinfo_size;
+extern unsigned int vmcoreinfo_max_size;
#else /* !CONFIG_KEXEC */