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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 27782C43457 for ; Thu, 8 Oct 2020 17:46:26 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6B54222202 for ; Thu, 8 Oct 2020 17:46:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B54222202 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B6C4E940007; Thu, 8 Oct 2020 13:46:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B1B56900002; Thu, 8 Oct 2020 13:46:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A5877940007; Thu, 8 Oct 2020 13:46:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0054.hostedemail.com [216.40.44.54]) by kanga.kvack.org (Postfix) with ESMTP id 7BCAD900002 for ; Thu, 8 Oct 2020 13:46:24 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 1B9F1181AE863 for ; Thu, 8 Oct 2020 17:46:24 +0000 (UTC) X-FDA: 77349487488.02.flag13_150c4e6271d9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id ED477101948D2 for ; Thu, 8 Oct 2020 17:46:23 +0000 (UTC) X-HE-Tag: flag13_150c4e6271d9 X-Filterd-Recvd-Size: 1823 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Thu, 8 Oct 2020 17:46:23 +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 BF51BAFC8; Thu, 8 Oct 2020 17:46:21 +0000 (UTC) Subject: Re: [PATCH v2 7/7] mm, page_alloc: disable pcplists during memory offline To: Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Pavel Tatashin , David Hildenbrand , Oscar Salvador , Joonsoo Kim References: <20201008114201.18824-1-vbabka@suse.cz> <20201008114201.18824-8-vbabka@suse.cz> <20201008124534.GD4967@dhcp22.suse.cz> From: Vlastimil Babka Message-ID: <0a19a42c-34fe-1f52-1e6e-d82295fa5ae7@suse.cz> Date: Thu, 8 Oct 2020 19:46:18 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <20201008124534.GD4967@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000024, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 10/8/20 2:45 PM, Michal Hocko wrote: > On Thu 08-10-20 13:42:01, Vlastimil Babka wrote: >> Memory offline relies on page isolation can race with process freeing pages to >> pcplists in a way that a page from isolated pageblock can end up on pcplist. > > "Memory offlining relies on page isolation to guarantee a forward > progress because pages cannot be reused while they are isolated. But the > page isolation itself doesn't prevent from races while freed pages are > stored on pcp lists and thus can be reused. > " Much better, thanks.