mm/migrate: remove the -EEXIST conversion for move_pages()

The -EEXIST conversion is introduced in commit 65462462ffb2 ("mm/gup:
follow_pfn_pte(): -EEXIST cleanup"), since follow_page() may call
follow_pfn_pte() which may return -EEXIST.

But after commit 7dff875c9436 ("mm/migrate: convert
add_page_for_migration() from follow_page() to folio_walk"), it use
folio_walk instead.  This limit the error code and won't return -EEXIST.

Remove the error code conversion here.

Link: https://lkml.kernel.org/r/20250707065711.18056-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Ying Huang <ying.huang@linux.alibaba.com>
Cc: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/migrate.c b/mm/migrate.c
index e4e05a98c84ee247e61eda9ccc2394ad98aeee8b..36b2764204b65abe5d5668d8bb31a63a449468a4 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2362,13 +2362,6 @@ static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes,
                        continue;
                }
 
-               /*
-                * The move_pages() man page does not have an -EEXIST choice, so
-                * use -EFAULT instead.
-                */
-               if (err == -EEXIST)
-                       err = -EFAULT;
-
                /*
                 * If the page is already on the target node (!err), store the
                 * node, otherwise, store the err.