diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index 4365ffdb461f52b946b8e71c5ffa6c250d7f12be..7e3f17f92c665ec79850eefa328567e06c50134c 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -29,18 +29,18 @@
 
 #define	MTRR_IOCTL_BASE	'M'
 
-struct mtrr_sentry {
-    unsigned long base;    /*  Base address     */
-    unsigned int size;    /*  Size of region   */
-    unsigned int type;     /*  Type of region   */
-};
-
 /* Warning: this structure has a different order from i386
    on x86-64. The 32bit emulation code takes care of that.
    But you need to use this for 64bit, otherwise your X server
    will break. */
 
 #ifdef __i386__
+struct mtrr_sentry {
+    unsigned long base;    /*  Base address     */
+    unsigned int size;    /*  Size of region   */
+    unsigned int type;     /*  Type of region   */
+};
+
 struct mtrr_gentry {
     unsigned int regnum;   /*  Register number  */
     unsigned long base;    /*  Base address     */
@@ -50,12 +50,20 @@ struct mtrr_gentry {
 
 #else /* __i386__ */
 
+struct mtrr_sentry {
+	__u64 base;		/*  Base address     */
+	__u32 size;		/*  Size of region   */
+	__u32 type;		/*  Type of region   */
+};
+
 struct mtrr_gentry {
-    unsigned long base;    /*  Base address     */
-    unsigned int size;    /*  Size of region   */
-    unsigned int regnum;   /*  Register number  */
-    unsigned int type;     /*  Type of region   */
+	__u64 base;		/*  Base address     */
+	__u32 size;		/*  Size of region   */
+	__u32 regnum;		/*  Register number  */
+	__u32 type;		/*  Type of region   */
+	__u32 _pad;		/*  Unused	     */
 };
+
 #endif /* !__i386__ */
 
 struct mtrr_var_range {
diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c
index 79289632cb270cb4aa02c1e5cc58d4c3de5b53b1..a041e094b8b9fd68a520d5952c8ed05a4bdd7380 100644
--- a/arch/x86/kernel/cpu/mtrr/if.c
+++ b/arch/x86/kernel/cpu/mtrr/if.c
@@ -167,6 +167,7 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
 {
 	int err = 0;
 	mtrr_type type;
+	unsigned long base;
 	unsigned long size;
 	struct mtrr_sentry sentry;
 	struct mtrr_gentry gentry;
@@ -267,14 +268,14 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
 #endif
 		if (gentry.regnum >= num_var_ranges)
 			return -EINVAL;
-		mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
+		mtrr_if->get(gentry.regnum, &base, &size, &type);
 
 		/* Hide entries that go above 4GB */
-		if (gentry.base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
+		if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
 		    || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
 			gentry.base = gentry.size = gentry.type = 0;
 		else {
-			gentry.base <<= PAGE_SHIFT;
+			gentry.base = base << PAGE_SHIFT;
 			gentry.size = size << PAGE_SHIFT;
 			gentry.type = type;
 		}
@@ -321,11 +322,12 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
 #endif
 		if (gentry.regnum >= num_var_ranges)
 			return -EINVAL;
-		mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
+		mtrr_if->get(gentry.regnum, &base, &size, &type);
 		/* Hide entries that would overflow */
 		if (size != (__typeof__(gentry.size))size)
 			gentry.base = gentry.size = gentry.type = 0;
 		else {
+			gentry.base = base;
 			gentry.size = size;
 			gentry.type = type;
 		}