[PATCH 1/3] mm/gup: Use huge_ptep_get() in gup_hugepte()

[Christophe Leroy]

gup_hugepte() reads hugepage table entries, it can't read
them directly, huge_ptep_get() must be used.

Fixes: 2ab3a0a02905 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() 
memory accesses")
Cc: Will Deacon <w...@kernel.org>
Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
 mm/gup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/gup.c b/mm/gup.c
index de9e36262ccb..761df4944ef5 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2425,7 +2425,7 @@ static int gup_hugepte(pte_t *ptep, unsigned long sz, 
unsigned long addr,
        if (pte_end < end)
                end = pte_end;
 
-       pte = READ_ONCE(*ptep);
+       pte = huge_ptep_get(ptep);
 
        if (!pte_access_permitted(pte, flags & FOLL_WRITE))
                return 0;
-- 
2.25.0