From 3218f8712d6bba1812efd5e0d66c1e15134f2a91 Mon Sep 17 00:00:00 2001 From: Alex Sierra Date: Fri, 15 Jul 2022 10:05:11 -0500 Subject: mm: handling Non-LRU pages returned by vm_normal_pages With DEVICE_COHERENT, we'll soon have vm_normal_pages() return device-managed anonymous pages that are not LRU pages. Although they behave like normal pages for purposes of mapping in CPU page, and for COW. They do not support LRU lists, NUMA migration or THP. Callers to follow_page() currently don't expect ZONE_DEVICE pages, however, with DEVICE_COHERENT we might now return ZONE_DEVICE. Check for ZONE_DEVICE pages in applicable users of follow_page() as well. Link: https://lkml.kernel.org/r/20220715150521.18165-5-alex.sierra@amd.com Signed-off-by: Alex Sierra Acked-by: Felix Kuehling [v2] Reviewed-by: Alistair Popple [v6] Cc: Christoph Hellwig Cc: David Hildenbrand Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: Matthew Wilcox Cc: Ralph Campbell Signed-off-by: Andrew Morton --- mm/migrate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index 7934eebf1689..1649270bc1a7 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1630,7 +1630,7 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, goto out; err = -ENOENT; - if (!page) + if (!page || is_zone_device_page(page)) goto out; err = 0; @@ -1821,7 +1821,7 @@ static void do_pages_stat_array(struct mm_struct *mm, unsigned long nr_pages, if (IS_ERR(page)) goto set_status; - if (page) { + if (page && !is_zone_device_page(page)) { err = page_to_nid(page); put_page(page); } else { -- cgit v1.2.3