From a8f6e7f7953d1baa05a346bf7cee44f1d022c63d Mon Sep 17 00:00:00 2001
From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Wed, 5 Jun 2013 09:25:34 +0200
Subject: [PATCH] s390/pgtable: make pgste lock an explicit barrier

Getting and Releasing the pgste lock has lock semantics. Make the
code an explicit barrier.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/include/asm/pgtable.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index f9a0a70dc9367..e8b6e5b8932c3 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -623,7 +623,7 @@ static inline pgste_t pgste_get_lock(pte_t *ptep)
 		"	csg	%0,%1,%2\n"
 		"	jl	0b\n"
 		: "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE])
-		: "Q" (ptep[PTRS_PER_PTE]) : "cc");
+		: "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory");
 #endif
 	return __pgste(new);
 }
@@ -635,7 +635,8 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
 		"	nihh	%1,0xff7f\n"	/* clear RCP_PCL_BIT */
 		"	stg	%1,%0\n"
 		: "=Q" (ptep[PTRS_PER_PTE])
-		: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE]) : "cc");
+		: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
+		: "cc", "memory");
 	preempt_enable();
 #endif
 }
-- 
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