On Fri, Jan 17, 2020 at 03:45:34PM +0800, Wei Yang wrote: >If we get here after successfully adding page to list, err would be >the number of pages in the list. > >Current code has two problems: > > * on success, 0 is not returned > * on error, the real error code is not returned > Well, this breaks the user interface. User would receive 1 even the migration succeed. The change is introduced by e0153fc2c760 ("mm: move_pages: return valid node id in status if the page is already on the target node"). >Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> >--- > mm/migrate.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/mm/migrate.c b/mm/migrate.c >index 557da996b936..c3ef70de5876 100644 >--- a/mm/migrate.c >+++ b/mm/migrate.c >@@ -1677,7 +1677,7 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, > err1 = do_move_pages_to_node(mm, &pagelist, current_node); > if (!err1) > err1 = store_status(status, start, current_node, i - start); >- if (!err) >+ if (err >= 0) > err = err1; > out: > return err; >-- >2.17.1 -- Wei Yang Help you, Help me