From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> commit dfe9aa23cab7880a794db9eb2d176c00ed064eb6 upstream. 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> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/migrate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/migrate.c +++ b/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;