| Message ID | 20220916072257.9639-9-linmiaohe@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | A few cleanup patches for mm | expand |
On 16.09.22 09:22, Miaohe Lin wrote: > In MIGRATE_ISOLATE case, zone freepage state shouldn't be modified as > caller will take care of it. Add missing is_migrate_isolate() here to > avoid possible unbalanced freepage state. This would happen if someone > isolates the block, and then we face an MCE failure/soft-offline on a > page within that block. __mod_zone_freepage_state() will be triggered > via below call trace which already had been triggered back when block > was isolated: > > take_page_off_buddy > break_down_buddy_pages > set_page_guard > > Fixes: 06be6ff3d2ec ("mm,hwpoison: rework soft offline for free pages") > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> > Reviewed-by: Oscar Salvador <osalvador@suse.de> > --- Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index cad235770948..8fcc905ef317 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -873,7 +873,8 @@ static inline bool set_page_guard(struct zone *zone, struct page *page, INIT_LIST_HEAD(&page->buddy_list); set_page_private(page, order); /* Guard pages are not available for any usage */ - __mod_zone_freepage_state(zone, -(1 << order), migratetype); + if (!is_migrate_isolate(migratetype)) + __mod_zone_freepage_state(zone, -(1 << order), migratetype); return true; }
In MIGRATE_ISOLATE case, zone freepage state shouldn't be modified as caller will take care of it. Add missing is_migrate_isolate() here to avoid possible unbalanced freepage state. This would happen if someone isolates the block, and then we face an MCE failure/soft-offline on a page within that block. __mod_zone_freepage_state() will be triggered via below call trace which already had been triggered back when block was isolated: take_page_off_buddy break_down_buddy_pages set_page_guard Fixes: 06be6ff3d2ec ("mm,hwpoison: rework soft offline for free pages") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> --- mm/page_alloc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)