On Tue, Jan 5, 2021 at 6:14 AM Jan Stancek <[email protected]> wrote: > > After commit 236c32eb1096 ("mm: migrate: clean up migrate_prep{_local}")', > do_migrate_pages can return uninitialized variable 'err' (which is > propagated to user-space as error) when 'from' and 'to' nodesets > are identical. This can be reproduced with LTP migrate_pages01, > which calls migrate_pages() with same set for both old/new_nodes. > > Add 'err' initialization back.
Thanks for catching this. Acked-by: Yang Shi <[email protected]> > > Fixes: 236c32eb1096 ("mm: migrate: clean up migrate_prep{_local}") > Cc: Zi Yan <[email protected]> > Cc: Yang Shi <[email protected]> > Cc: Jan Kara <[email protected]> > Cc: Matthew Wilcox <[email protected]> > Cc: Mel Gorman <[email protected]> > Cc: Michal Hocko <[email protected]> > Cc: Song Liu <[email protected]> > Cc: Andrew Morton <[email protected]> > Signed-off-by: Jan Stancek <[email protected]> > --- > mm/mempolicy.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 8cf96bd21341..2c3a86502053 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -1111,7 +1111,7 @@ int do_migrate_pages(struct mm_struct *mm, const > nodemask_t *from, > const nodemask_t *to, int flags) > { > int busy = 0; > - int err; > + int err = 0; > nodemask_t tmp; > > migrate_prep(); > -- > 2.18.1 >
