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=-8.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 B9D7FC433DF for ; Mon, 24 Aug 2020 12:07:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 803A82078D for ; Mon, 24 Aug 2020 12:07:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 803A82078D 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 0B1716B000A; Mon, 24 Aug 2020 08:07:41 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 062106B000D; Mon, 24 Aug 2020 08:07:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E91A26B000E; Mon, 24 Aug 2020 08:07:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0216.hostedemail.com [216.40.44.216]) by kanga.kvack.org (Postfix) with ESMTP id CF92A6B000A for ; Mon, 24 Aug 2020 08:07:40 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id E20D08248047 for ; Mon, 24 Aug 2020 12:07:39 +0000 (UTC) X-FDA: 77185337838.20.pet40_4a0a09727053 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin20.hostedemail.com (Postfix) with ESMTP id 93D73180C1474 for ; Mon, 24 Aug 2020 12:07:17 +0000 (UTC) X-HE-Tag: pet40_4a0a09727053 X-Filterd-Recvd-Size: 2692 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf12.hostedemail.com (Postfix) with ESMTP for ; Mon, 24 Aug 2020 12:07:17 +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 CC1D3AC19; Mon, 24 Aug 2020 12:07:45 +0000 (UTC) Date: Mon, 24 Aug 2020 14:07:13 +0200 From: Oscar Salvador To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Michal Hocko , Andrew Morton , Wei Yang , Baoquan He , Pankaj Gupta , Charan Teja Reddy Subject: Re: [PATCH v2 10/10] mm/memory_hotplug: mark pageblocks MIGRATE_ISOLATE while onlining memory Message-ID: <20200824120713.GB7491@linux> References: <20200819175957.28465-1-david@redhat.com> <20200819175957.28465-11-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200819175957.28465-11-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: 93D73180C1474 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 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: On Wed, Aug 19, 2020 at 07:59:57PM +0200, David Hildenbrand wrote: > Currently, it can happen that pages are allocated (and freed) via the buddy > before we finished basic memory onlining. > > For example, pages are exposed to the buddy and can be allocated before > we actually mark the sections online. Allocated pages could suddenly > fail pfn_to_online_page() checks. We had similar issues with pcp > handling, when pages are allocated+freed before we reach > zone_pcp_update() in online_pages() [1]. > > Instead, mark all pageblocks MIGRATE_ISOLATE, such that allocations are > impossible. Once done with the heavy lifting, use > undo_isolate_page_range() to move the pages to the MIGRATE_MOVABLE > freelist, marking them ready for allocation. Similar to offline_pages(), > we have to manually adjust zone->nr_isolate_pageblock. > > [1] https://lkml.kernel.org/r/1597150703-19003-1-git-send-email-charante@codeaurora.org > > Acked-by: Michal Hocko > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Wei Yang > Cc: Baoquan He > Cc: Pankaj Gupta > Cc: Oscar Salvador > Cc: Charan Teja Reddy > Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador -- Oscar Salvador SUSE L3