Package: linux / 3.16.56-1+deb8u1

bugfix/all/access_once/0005-mips-gup-Replace-ACCESS_ONCE-with-READ_ONCE.patch Patch series | download
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From: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Fri, 21 Nov 2014 16:21:56 +0100
Subject: mips/gup: Replace ACCESS_ONCE with READ_ONCE
Origin: https://git.kernel.org/linus/4218091cb45f601b889cd032e39fe6878a426e70

ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the gup code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 arch/mips/mm/gup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/mm/gup.c
+++ b/arch/mips/mm/gup.c
@@ -30,7 +30,7 @@ retry:
 
 	return pte;
 #else
-	return ACCESS_ONCE(*ptep);
+	return READ_ONCE(*ptep);
 #endif
 }