From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Subject: mm/migrate.c: also overwrite error when it is bigger than zero
If we get here after successfully adding page to list, err would be 1 to
indicate the page is queued in the list.
Current code has two problems:
* on success, 0 is not returned
* on error, if add_page_for_migratioin() return 1, and the following err1
from do_move_pages_to_node() is set, the err1 is not returned since err
is 1
And these behaviors break the user interface.
Link: http://lkml.kernel.org/r/20200119065753.21694-1-richardw.yang@xxxxxxxxxxxxxxx
Fixes: 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>
Acked-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/migrate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/migrate.c~mm-migratec-also-overwrite-error-when-it-is-bigger-than-zero
+++ a/mm/migrate.c
@@ -1676,7 +1676,7 @@ out_flush:
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;
_
