From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A3FDC433FE for ; Fri, 18 Nov 2022 10:17:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241448AbiKRKRm (ORCPT ); Fri, 18 Nov 2022 05:17:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46046 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241435AbiKRKRi (ORCPT ); Fri, 18 Nov 2022 05:17:38 -0500 Received: from outbound-smtp29.blacknight.com (outbound-smtp29.blacknight.com [81.17.249.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 73A846153F for ; Fri, 18 Nov 2022 02:17:36 -0800 (PST) Received: from mail.blacknight.com (pemlinmail03.blacknight.ie [81.17.254.16]) by outbound-smtp29.blacknight.com (Postfix) with ESMTPS id 2883ABEC19 for ; Fri, 18 Nov 2022 10:17:35 +0000 (GMT) Received: (qmail 3723 invoked from network); 18 Nov 2022 10:17:35 -0000 Received: from unknown (HELO morpheus.112glenside.lan) (mgorman@techsingularity.net@[84.203.198.246]) by 81.17.254.9 with ESMTPA; 18 Nov 2022 10:17:34 -0000 From: Mel Gorman To: Andrew Morton Cc: Hugh Dickins , Yu Zhao , Vlastimil Babka , Marcelo Tosatti , Michal Hocko , Marek Szyprowski , LKML , Linux-MM , Mel Gorman Subject: [PATCH 1/2] mm/page_alloc: Always remove pages from temporary list Date: Fri, 18 Nov 2022 10:17:13 +0000 Message-Id: <20221118101714.19590-2-mgorman@techsingularity.net> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20221118101714.19590-1-mgorman@techsingularity.net> References: <20221118101714.19590-1-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org free_unref_page_list() has neglected to remove pages properly from the list of pages to free since forever. It works by coincidence because list_add happened to do the right thing adding the pages to just the PCP lists. However, a later patch added pages to either the PCP list or the zone list but only properly deleted the page from the list in one path leading to list corruption and a subsequent failure. As a preparation patch, always delete the pages from one list properly before adding to another. On its own, this fixes nothing although it adds a fractional amount of overhead but is critical to the next patch. Reported-by: Hugh Dickins Signed-off-by: Mel Gorman --- mm/page_alloc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 218b28ee49ed..1ec54173b8d4 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3546,6 +3546,8 @@ void free_unref_page_list(struct list_head *list) list_for_each_entry_safe(page, next, list, lru) { struct zone *zone = page_zone(page); + list_del(&page->lru); + /* Different zone, different pcp lock. */ if (zone != locked_zone) { if (pcp) -- 2.35.3