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Subject[PATCH 5/8] mips/gup: Replace ACCESS_ONCE with READ_ONCE
Date
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(-)

diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c
index 06ce17c..8aa50e3 100644
--- 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
}

--
1.9.3


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