[RFC v1 1/2] fixup for 9947ea2c1e608e32669d5caeb67b3e3fba3309e8 "mm/gup: track FOLL_PIN pages"

Claudio Imbrenda
2020-02-28T15:43:33Z

in case pin fails, we need to unpin, just a put_page will not be enough

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
---
mm/gup.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/mm/gup.c b/mm/gup.c
index f589299b0d4a..0b9a806898f3 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2134,7 +2134,10 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
goto pte_unmap;

if (unlikely(pte_val(pte) != pte_val(*ptep))) {
- put_page(head);
+ if (flags & FOLL_GET)
+ put_page(head);
+ else if (flags & FOLL_PIN)
+ unpin_user_page(head);
goto pte_unmap;
}

--
2.24.1