[PATCHv2 05/10] x86: Replace ACCESS_ONCE in gup with READ_ONCE

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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

Change the gup code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
 arch/x86/mm/gup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index 207d9aef..d754782 100644
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -15,7 +15,7 @@
 static inline pte_t gup_get_pte(pte_t *ptep)
 #ifndef CONFIG_X86_PAE
-	return ACCESS_ONCE(*ptep);
+	return READ_ONCE(*ptep);
 	 * With get_user_pages_fast, we walk down the pagetables without taking

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