diff mbox series

[14/16] mm: switch gup_hugepte to use try_get_compound_head

Message ID 20190611144102.8848-15-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/16] mm: use untagged_addr() for get_user_pages_fast addresses | expand

Commit Message

Christoph Hellwig June 11, 2019, 2:41 p.m. UTC 
This applies the overflow fixes from 8fde12ca79aff
("mm: prevent get_user_pages() from overflowing page refcount")
to the powerpc hugepd code and brings it back in sync with the
other GUP cases.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 mm/gup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/mm/gup.c b/mm/gup.c
index 494aa4c3a55e..0733674b539d 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2007,7 +2007,8 @@  static int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
 		refs++;
 	} while (addr += PAGE_SIZE, addr != end);
 
-	if (!page_cache_add_speculative(head, refs)) {
+	head = try_get_compound_head(head, refs);
+	if (!head) {
 		*nr -= refs;
 		return 0;
 	}