From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f72.google.com (mail-wm0-f72.google.com [74.125.82.72]) by kanga.kvack.org (Postfix) with ESMTP id A67B16B025E for ; Thu, 1 Dec 2016 19:22:47 -0500 (EST) Received: by mail-wm0-f72.google.com with SMTP id w13so381699wmw.0 for ; Thu, 01 Dec 2016 16:22:47 -0800 (PST) Received: from outbound-smtp06.blacknight.com (outbound-smtp06.blacknight.com. [81.17.249.39]) by mx.google.com with ESMTPS id y130si520988wmc.29.2016.12.01.16.22.45 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 01 Dec 2016 16:22:45 -0800 (PST) Received: from mail.blacknight.com (pemlinmail02.blacknight.ie [81.17.254.11]) by outbound-smtp06.blacknight.com (Postfix) with ESMTPS id 2938E98BA3 for ; Fri, 2 Dec 2016 00:22:45 +0000 (UTC) From: Mel Gorman Subject: [PATCH 1/2] mm, page_alloc: Keep pcp count and list contents in sync if struct page is corrupted Date: Fri, 2 Dec 2016 00:22:43 +0000 Message-Id: <20161202002244.18453-2-mgorman@techsingularity.net> In-Reply-To: <20161202002244.18453-1-mgorman@techsingularity.net> References: <20161202002244.18453-1-mgorman@techsingularity.net> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Christoph Lameter , Michal Hocko , Vlastimil Babka , Johannes Weiner , Jesper Dangaard Brouer , Linux-MM , Linux-Kernel , Mel Gorman Vlastimil Babka pointed out that commit 479f854a207c ("mm, page_alloc: defer debugging checks of pages allocated from the PCP") will allow the per-cpu list counter to be out of sync with the per-cpu list contents if a struct page is corrupted. This patch keeps the accounting in sync. Fixes: 479f854a207c ("mm, page_alloc: defer debugging checks of pages allocated from the PCP") Signed-off-by: Mel Gorman cc: stable@vger.kernel.org [4.7+] --- mm/page_alloc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6de9440e3ae2..777ed59570df 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2192,7 +2192,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, unsigned long count, struct list_head *list, int migratetype, bool cold) { - int i; + int i, alloced = 0; spin_lock(&zone->lock); for (i = 0; i < count; ++i) { @@ -2217,13 +2217,14 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order, else list_add_tail(&page->lru, list); list = &page->lru; + alloced++; if (is_migrate_cma(get_pcppage_migratetype(page))) __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, -(1 << order)); } __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); spin_unlock(&zone->lock); - return i; + return alloced; } #ifdef CONFIG_NUMA -- 2.10.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org