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 X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85264C43457 for ; Tue, 13 Oct 2020 14:43:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0B34024884 for ; Tue, 13 Oct 2020 14:43:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0B34024884 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 712976B0068; Tue, 13 Oct 2020 10:43:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6CA706B006C; Tue, 13 Oct 2020 10:43:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4A3836B006E; Tue, 13 Oct 2020 10:43:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0043.hostedemail.com [216.40.44.43]) by kanga.kvack.org (Postfix) with ESMTP id 36F286B0068 for ; Tue, 13 Oct 2020 10:43:40 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id E868A181AC9C6 for ; Tue, 13 Oct 2020 14:43:39 +0000 (UTC) X-FDA: 77367170958.29.idea94_170b69427204 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id F1D1B180868D5 for ; Tue, 13 Oct 2020 14:43:37 +0000 (UTC) X-HE-Tag: idea94_170b69427204 X-Filterd-Recvd-Size: 2979 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf28.hostedemail.com (Postfix) with ESMTP for ; Tue, 13 Oct 2020 14:43:36 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E0B48AEE5; Tue, 13 Oct 2020 14:43:33 +0000 (UTC) From: Oscar Salvador To: n-horiguchi@ah.jp.nec.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Oscar Salvador , Naoya Horiguchi Subject: [PATCH v5 1/4] mm,hwpoison: drain pcplists before bailing out for non-buddy zero-refcount page Date: Tue, 13 Oct 2020 16:44:44 +0200 Message-Id: <20201013144447.6706-2-osalvador@suse.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201013144447.6706-1-osalvador@suse.de> References: <20201013144447.6706-1-osalvador@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: A page with 0-refcount and !PageBuddy could perfectly be a pcppage. Currently, we bail out with an error if we encounter such a page, meaning that we do not handle pcppages neither from hard-offline nor from soft-offline path. Fix this by draining pcplists whenever we find this kind of page and retr= y the check again. It might be that pcplists have been spilled into the buddy allocator and so we can handle it. Signed-off-by: Oscar Salvador Acked-by: Naoya Horiguchi --- mm/memory-failure.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index c0bb186bba62..e2f12410c594 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -946,13 +946,13 @@ static int page_action(struct page_state *ps, struc= t page *p, } =20 /** - * get_hwpoison_page() - Get refcount for memory error handling: + * __get_hwpoison_page() - Get refcount for memory error handling: * @page: raw error page (hit by memory error) * * Return: return 0 if failed to grab the refcount, otherwise true (some * non-zero value.) */ -static int get_hwpoison_page(struct page *page) +static int __get_hwpoison_page(struct page *page) { struct page *head =3D compound_head(page); =20 @@ -982,6 +982,26 @@ static int get_hwpoison_page(struct page *page) return 0; } =20 +static int get_hwpoison_page(struct page *p) +{ + int ret; + bool drained =3D false; + +retry: + ret =3D __get_hwpoison_page(p); + if (!ret && !is_free_buddy_page(p) && !page_count(p) && !drained) { + /* + * The page might be in a pcplist, so try to drain those + * and see if we are lucky. + */ + drain_all_pages(page_zone(p)); + drained =3D true; + goto retry; + } + + return ret; +} + /* * Do all that is necessary to remove user space mappings. Unmap * the pages and send SIGBUS to the processes if the data was dirty. --=20 2.26.2