From: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Subject: 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/20180423072101.GA12157@xxxxxxxxxxxxxxxxxxxxxxxxxxxx Fixes: e71769ae5260 ("mm: enable thp migration for shmem thp") Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Reported-by: Matthew Wilcox <willy@xxxxxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Zi Yan <zi.yan@xxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/migrate.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff -puN mm/migrate.c~mm-migrate-fix-double-call-of-radix_tree_replace_slot mm/migrate.c --- a/mm/migrate.c~mm-migrate-fix-double-call-of-radix_tree_replace_slot +++ a/mm/migrate.c @@ -528,14 +528,12 @@ int migrate_page_move_mapping(struct add 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); } /* _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
