4 files changed, 20 insertions, 33 deletions

diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 2f1b7217c25c..0e64f08d3d69 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -43,13 +43,13 @@ static int machine_kdump_pm_cb(struct notifier_block *nb, unsigned long action,
 	switch (action) {
 	case PM_SUSPEND_PREPARE:
 	case PM_HIBERNATION_PREPARE:
-		if (crashk_res.start)
-			crash_map_reserved_pages();
+		if (kexec_crash_image)
+			arch_kexec_unprotect_crashkres();
 		break;
 	case PM_POST_SUSPEND:
 	case PM_POST_HIBERNATION:
-		if (crashk_res.start)
-			crash_unmap_reserved_pages();
+		if (kexec_crash_image)
+			arch_kexec_protect_crashkres();
 		break;
 	default:
 		return NOTIFY_DONE;
@@ -60,6 +60,8 @@ static int machine_kdump_pm_cb(struct notifier_block *nb, unsigned long action,
 static int __init machine_kdump_pm_init(void)
 {
 	pm_notifier(machine_kdump_pm_cb, 0);
+	/* Create initial mapping for crashkernel memory */
+	arch_kexec_unprotect_crashkres();
 	return 0;
 }
 arch_initcall(machine_kdump_pm_init);
@@ -146,6 +148,8 @@ static int kdump_csum_valid(struct kimage *image)
 #endif
 }
 
+#ifdef CONFIG_CRASH_DUMP
+
 /*
  * Map or unmap crashkernel memory
  */
@@ -167,21 +171,25 @@ static void crash_map_pages(int enable)
 }
 
 /*
- * Map crashkernel memory
+ * Unmap crashkernel memory
  */
-void crash_map_reserved_pages(void)
+void arch_kexec_protect_crashkres(void)
 {
-	crash_map_pages(1);
+	if (crashk_res.end)
+		crash_map_pages(0);
 }
 
 /*
- * Unmap crashkernel memory
+ * Map crashkernel memory
  */
-void crash_unmap_reserved_pages(void)
+void arch_kexec_unprotect_crashkres(void)
 {
-	crash_map_pages(0);
+	if (crashk_res.end)
+		crash_map_pages(1);
 }
 
+#endif
+
 /*
  * Give back memory to hypervisor before new kdump is loaded
  */
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 643ff4a3fbf6..e8acb2b43dd9 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -230,8 +230,6 @@ 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 crash_map_reserved_pages(void);
-void crash_unmap_reserved_pages(void);
 void arch_crash_save_vmcoreinfo(void);
 __printf(1, 2)
 void vmcoreinfo_append_str(const char *fmt, ...);
diff --git a/kernel/kexec.c b/kernel/kexec.c
index b73dc211fcfd..4384672d3245 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -136,9 +136,6 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
 	if (ret)
 		return ret;
 
-	if (flags & KEXEC_ON_CRASH)
-		crash_map_reserved_pages();
-
 	if (flags & KEXEC_PRESERVE_CONTEXT)
 		image->preserve_context = 1;
 
@@ -161,12 +158,6 @@ out:
 	if ((flags & KEXEC_ON_CRASH) && kexec_crash_image)
 		arch_kexec_protect_crashkres();
 
-	/*
-	 * Once the reserved memory is mapped, we should unmap this memory
-	 * before returning
-	 */
-	if (flags & KEXEC_ON_CRASH)
-		crash_unmap_reserved_pages();
 	kimage_free(image);
 	return ret;
 }
@@ -232,9 +223,6 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 
 	result = do_kexec_load(entry, nr_segments, segments, flags);
 
-	if ((flags & KEXEC_ON_CRASH) && kexec_crash_image)
-		arch_kexec_protect_crashkres();
-
 	mutex_unlock(&kexec_mutex);
 
 	return result;
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 48b73cc8e425..56b3ed0927b0 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -954,7 +954,6 @@ int crash_shrink_memory(unsigned long new_size)
 	start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
 	end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
 
-	crash_map_reserved_pages();
 	crash_free_reserved_phys_range(end, crashk_res.end);
 
 	if ((start == end) && (crashk_res.parent != NULL))
@@ -968,7 +967,6 @@ int crash_shrink_memory(unsigned long new_size)
 	crashk_res.end = end - 1;
 
 	insert_resource(&iomem_resource, ram_res);
-	crash_unmap_reserved_pages();
 
 unlock:
 	mutex_unlock(&kexec_mutex);
@@ -1553,17 +1551,12 @@ int kernel_kexec(void)
 }
 
 /*
- * Add and remove page tables for crashkernel memory
+ * Protection mechanism for crashkernel reserved memory after
+ * the kdump kernel is loaded.
  *
  * Provide an empty default implementation here -- architecture
  * code may override this
  */
-void __weak crash_map_reserved_pages(void)
-{}
-
-void __weak crash_unmap_reserved_pages(void)
-{}
-
 void __weak arch_kexec_protect_crashkres(void)
 {}