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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 ACFB2C433FF for ; Sat, 10 Aug 2019 09:21:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85645208C3 for ; Sat, 10 Aug 2019 09:21:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726144AbfHJJSq (ORCPT ); Sat, 10 Aug 2019 05:18:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59422 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725865AbfHJJSq (ORCPT ); Sat, 10 Aug 2019 05:18:46 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8AA85300C72E; Sat, 10 Aug 2019 09:18:45 +0000 (UTC) Received: from [10.36.116.22] (ovpn-116-22.ams2.redhat.com [10.36.116.22]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E2485D9E2; Sat, 10 Aug 2019 09:18:42 +0000 (UTC) Subject: Re: [PATCH v1 2/4] mm/memory_hotplug: Handle unaligned start and nr_pages in online_pages_blocks() To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Arun KS , Oscar Salvador , Michal Hocko , Pavel Tatashin , Dan Williams , Sasha Levin References: <20190809125701.3316-1-david@redhat.com> <20190809125701.3316-3-david@redhat.com> <20190809144602.eddc3827a373f17ddda7d069@linux-foundation.org> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190809144602.eddc3827a373f17ddda7d069@linux-foundation.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Sat, 10 Aug 2019 09:18:45 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09.08.19 23:46, Andrew Morton wrote: > On Fri, 9 Aug 2019 14:56:59 +0200 David Hildenbrand wrote: > >> Take care of nr_pages not being a power of two and start not being >> properly aligned. Essentially, what walk_system_ram_range() could provide >> to us. get_order() will round-up in case it's not a power of two. >> >> This should only apply to memory blocks that contain strange memory >> resources (especially with holes), not to ordinary DIMMs. > > I'm assuming this doesn't fix any known runtime problem and that a > -stable backport isn't needed. Yeah, my understanding is that this would only apply when offlining and re-onlining boot memory that contains such weird memory holes. I don't think this is stable material. Thanks! > >> Fixes: a9cd410a3d29 ("mm/page_alloc.c: memory hotplug: free pages as higher order") > > To that end, I replaced this with my new "Fixes-no-stable" in order to > discourage -stable maintainers from overriding our decision. > >> Cc: Arun KS >> Cc: Andrew Morton >> Cc: Oscar Salvador >> Cc: Michal Hocko >> Cc: Pavel Tatashin >> Cc: Dan Williams >> Signed-off-by: David Hildenbrand -- Thanks, David / dhildenb