kdump, vmcoreinfo: report memory sections virtual addresses

KASLR memory randomization can randomize the base of the physical memory
mapping (PAGE_OFFSET), vmalloc (VMALLOC_START) and vmemmap
(VMEMMAP_START).  Adding these variables on VMCOREINFO so tools can easily
identify the base of each memory section.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Garnier <[email protected]>
Acked-by: Baoquan He <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H . Peter Anvin" <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: Xunlei Pang <[email protected]>
Cc: HATAYAMA Daisuke <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Eugene Surovegin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 5a294e48b18529045ae4371f4ef8dc281773aea8..8c1f218926d783ecb8d288f9fc340379695089a7 100644 (file)
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -337,6 +337,9 @@ void arch_crash_save_vmcoreinfo(void)
 #endif
        vmcoreinfo_append_str("KERNELOFFSET=%lx\n",
                              kaslr_offset());
+       VMCOREINFO_PAGE_OFFSET(PAGE_OFFSET);
+       VMCOREINFO_VMALLOC_START(VMALLOC_START);
+       VMCOREINFO_VMEMMAP_START(VMEMMAP_START);
 }
 
 /* arch-dependent functionality related to kexec file-based syscall */

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index d7437777baaafe382458df9115b005f764a064f5..406c33dcae137a62af7e7d78edf11938270a45c9 100644 (file)
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -259,6 +259,12 @@ phys_addr_t paddr_vmcoreinfo_note(void);
        vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 #define VMCOREINFO_CONFIG(name) \
        vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
+#define VMCOREINFO_PAGE_OFFSET(value) \
+       vmcoreinfo_append_str("PAGE_OFFSET=%lx\n", (unsigned long)value)
+#define VMCOREINFO_VMALLOC_START(value) \
+       vmcoreinfo_append_str("VMALLOC_START=%lx\n", (unsigned long)value)
+#define VMCOREINFO_VMEMMAP_START(value) \
+       vmcoreinfo_append_str("VMEMMAP_START=%lx\n", (unsigned long)value)
 
 extern struct kimage *kexec_image;
 extern struct kimage *kexec_crash_image;