tree ec24c8eeedbb75fad4e2f3e4177d8c96a82777bd
parent 059eaf82c0e1559a4bbd00847a11109eb0159db2
author Jan Stancek <jstancek@redhat.com> 1610495361 -0800
committer Minchan Kim <minchan@google.com> 1615581352 -0800

UPSTREAM: mm: migrate: initialize err in do_migrate_pages

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.

Bug: 180018981
Link: https://lkml.kernel.org/r/456a021c7ef3636d7668cec9dcb4a446a4244812.1609855564.git.jstancek@redhat.com
Fixes: 236c32eb1096 ("mm: migrate: clean up migrate_prep{_local}")
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit f555befd185dc097ede887eb7b308c2e1c1369d4)
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: Ia0b7012dc4191bf3af5ca015939d9e37a1f7ec43