mm: migrate: fix double call of radix_tree_replace_slot()

radix_tree_replace_slot() is called twice for head page, it's obviously a bug. Let's fix it. Link: http://lkml.kernel.org/r/[email protected] Fixes: e71769a ("mm: enable thp migration for shmem thp") Signed-off-by: Naoya Horiguchi <[email protected]> Reported-by: Matthew Wilcox <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Cc: Michal Hocko <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Zi Yan <[email protected]> Cc: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · May 12, 2018 · 013567b · 013567b
1 parent 3955333
commit 013567b
Showing 1 changed file with 1 addition and 3 deletions.
diff --git a/mm/migrate.c b/mm/migrate.c
@@ -528,14 +528,12 @@ int migrate_page_move_mapping(struct address_space *mapping,
 		int i;
 		int index = page_index(page);
 
-		for (i = 0; i < HPAGE_PMD_NR; i++) {
+		for (i = 1; i < HPAGE_PMD_NR; i++) {
 			pslot = radix_tree_lookup_slot(&mapping->i_pages,
 						       index + i);
 			radix_tree_replace_slot(&mapping->i_pages, pslot,
 						newpage + i);
 		}
-	} else {
-		radix_tree_replace_slot(&mapping->i_pages, pslot, newpage);
 	}
 
 	/*