[RFC v1 07/17] gup: add non-caching get_user call to fault_in_readable()

[Gatlin Newhouse]

Adds non-caching call to fault_in_readable() for configurations with
SafeFetch enabled and disabled readable pages.
---
 mm/gup.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/mm/gup.c b/mm/gup.c
index 3c39cbbeebef..69d2d110da3f 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2224,7 +2224,11 @@ size_t fault_in_readable(const char __user *uaddr, 
size_t size)
 
        /* Stop once we overflow to 0. */
        for (cur = start; cur && cur < end; cur = PAGE_ALIGN_DOWN(cur + 
PAGE_SIZE))
+#if defined(CONFIG_SAFEFETCH) && !defined(SAFEFETCH_PROTECT_PAGES_READABLE)
+               unsafe_get_user_no_dfcache(c, (const char __user *)cur, out);
+#else
                unsafe_get_user(c, (const char __user *)cur, out);
+#endif
 out:
        user_read_access_end();
        (void)c;
-- 
2.25.1