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From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Mon, 22 May 2017 13:27:34 +0200
Subject: s390/mm: remove incorrect _REGION3_ENTRY_ORIGIN define
Patch-mainline: v4.13-rc1
Git-commit: f96c6f72bc792e7add27e40ec859a8f5ea72e72b
References: bsc#1077761

_REGION3_ENTRY_ORIGIN defines a wrong mask which can be used to
extract a segment table origin from a region 3 table entry. It removes
only the lower 11 instead of 12 bits from a region 3 table entry.
Luckily this bit is currently always zero, so nothing bad happened yet.

In order to avoid future bugs just remove the region 3 specific mask
and use the correct generic _REGION_ENTRY_ORIGIN mask.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 arch/s390/include/asm/pgtable.h |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -296,8 +296,6 @@
 #define _REGION3_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID)
 
 #define _REGION3_ENTRY_ORIGIN_LARGE ~0x7fffffffUL /* large page address	     */
-#define _REGION3_ENTRY_ORIGIN  ~0x7ffUL/* region third table origin	     */
-
 #define _REGION3_ENTRY_DIRTY	0x2000	/* SW region dirty bit */
 #define _REGION3_ENTRY_YOUNG	0x1000	/* SW region young bit */
 #define _REGION3_ENTRY_LARGE	0x0400	/* RTTE-format control, large page  */
@@ -614,7 +612,7 @@
 {
 	unsigned long origin_mask;
 
-	origin_mask = _REGION3_ENTRY_ORIGIN;
+	origin_mask = _REGION_ENTRY_ORIGIN;
 	if (pud_large(pud))
 		origin_mask = _REGION3_ENTRY_ORIGIN_LARGE;
 	return (pud_val(pud) & origin_mask) >> PAGE_SHIFT;