From 59752bf03526a5ab4e3d825f7bb3fc5b6f456cfe Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yinghai@kernel.org>
Date: Thu, 24 Jan 2013 12:20:03 -0800
Subject: [PATCH] --- yaml --- r: 356247 b: refs/heads/master c:
 084d1283986a530828b8898f206adf44d5d3146d h: refs/heads/master i:   356245:
 c0de433b86af1db093871f620d3b6061a307b6f5   356243:
 9cb23bcc4c6f50694542b5ae21ca3810bdb2dd12   356239:
 884fc4090d1f19bb2f7f90439fa7a38bd5e5d6f3 v: v3

---
 [refs]                                   |  2 +-
 trunk/arch/x86/kernel/machine_kexec_64.c | 43 ++++++++++++++++++++----
 2 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 5e3d99de10da..580de38d2709 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 577af55d802d9fe114287e750504e09e7c677c9c
+refs/heads/master: 084d1283986a530828b8898f206adf44d5d3146d
diff --git a/trunk/arch/x86/kernel/machine_kexec_64.c b/trunk/arch/x86/kernel/machine_kexec_64.c
index b3ea9db39db6..be14ee120c43 100644
--- a/trunk/arch/x86/kernel/machine_kexec_64.c
+++ b/trunk/arch/x86/kernel/machine_kexec_64.c
@@ -56,6 +56,25 @@ static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
 	return result;
 }
 
+static int ident_mapping_init(struct kimage *image, pgd_t *level4p,
+				unsigned long mstart, unsigned long mend)
+{
+	int result;
+
+	mstart = round_down(mstart, PMD_SIZE);
+	mend   = round_up(mend - 1, PMD_SIZE);
+
+	while (mstart < mend) {
+		result = init_one_level2_page(image, level4p, mstart);
+		if (result)
+			return result;
+
+		mstart += PMD_SIZE;
+	}
+
+	return 0;
+}
+
 static void init_level2_page(pmd_t *level2p, unsigned long addr)
 {
 	unsigned long end_addr;
@@ -184,22 +203,34 @@ static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
 	return result;
 }
 
-
 static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
 {
+	unsigned long mstart, mend;
 	pgd_t *level4p;
 	int result;
+	int i;
+
 	level4p = (pgd_t *)__va(start_pgtable);
 	result = init_level4_page(image, level4p, 0, max_pfn << PAGE_SHIFT);
 	if (result)
 		return result;
+
 	/*
-	 * image->start may be outside 0 ~ max_pfn, for example when
-	 * jump back to original kernel from kexeced kernel
+	 * segments's mem ranges could be outside 0 ~ max_pfn,
+	 * for example when jump back to original kernel from kexeced kernel.
+	 * or first kernel is booted with user mem map, and second kernel
+	 * could be loaded out of that range.
 	 */
-	result = init_one_level2_page(image, level4p, image->start);
-	if (result)
-		return result;
+	for (i = 0; i < image->nr_segments; i++) {
+		mstart = image->segment[i].mem;
+		mend   = mstart + image->segment[i].memsz;
+
+		result = ident_mapping_init(image, level4p, mstart, mend);
+
+		if (result)
+			return result;
+	}
+
 	return init_transition_pgtable(image, level4p);
 }