From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Wed, 5 Jun 2013 07:22:33 +0000 (+0200)
Subject: s390/pgtable: Save pgste during modify_prot_start/commit
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=3a82603be4f5523ce21dd468a323aa36ff845f6d;p=deliverable%2Flinux.git

s390/pgtable: Save pgste during modify_prot_start/commit

In modify_prot_start we update the pgste value but never store it back
into the original location. Lets save the calculated result, since
modify_prot_commit will use the value of the pgste.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 391e592356d0..f9a0a70dc936 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -640,6 +640,13 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
 #endif
 }
 
+static inline void pgste_set(pte_t *ptep, pgste_t pgste)
+{
+#ifdef CONFIG_PGSTE
+	*(pgste_t *)(ptep + PTRS_PER_PTE) = pgste;
+#endif
+}
+
 static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste)
 {
 #ifdef CONFIG_PGSTE
@@ -1101,8 +1108,10 @@ static inline pte_t ptep_modify_prot_start(struct mm_struct *mm,
 	if (!mm_exclusive(mm))
 		__ptep_ipte(address, ptep);
 
-	if (mm_has_pgste(mm))
+	if (mm_has_pgste(mm)) {
 		pgste = pgste_update_all(&pte, pgste);
+		pgste_set(ptep, pgste);
+	}
 	return pte;
 }