Hi Miaohe,
On 3/4/2022 5:34 PM, Miaohe Lin wrote:
We should return errno (-EBUSY here) when failed to isolate the huge page
rather than always return 1 which could confuse the user.
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/migrate.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/mm/migrate.c b/mm/migrate.c
index 6c2dfed2ddb8..279940c0c064 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1618,10 +1618,8 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr,
goto out_putpage;
if (PageHuge(page)) {
- if (PageHead(page)) {
- isolate_huge_page(page, pagelist);
- err = 1;
- }
+ if (PageHead(page))
+ err = isolate_huge_page(page, pagelist) ? 1 : -EBUSY;
Could you elaborate on which case the huge page isolation can be failed
in this case? Or you met a real problem? Cause now we've got this head
huge page refcnt, I can not see why we'll fail to isolate this huge page.
