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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 B556BC76196 for ; Thu, 18 Jul 2019 16:43:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A5BA21850 for ; Thu, 18 Jul 2019 16:43:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=soleen.com header.i=@soleen.com header.b="Yi1h9o2C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390810AbfGRQnq (ORCPT ); Thu, 18 Jul 2019 12:43:46 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:41778 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732305AbfGRQnq (ORCPT ); Thu, 18 Jul 2019 12:43:46 -0400 Received: by mail-ed1-f68.google.com with SMTP id p15so30978008eds.8 for ; Thu, 18 Jul 2019 09:43:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+W9Fu950QMsufBfCCPx+AFaKU8cPICx7xAobprqzZjM=; b=Yi1h9o2CQwbo6Qwnob3MkuqbT3GZvCeRMRmamE2v3Oszki45i8Qs9f/kn68w0M2+LQ Ff3szsQU67WdJ6ROZ8QobqIZAfnu5yM69u/ZsjYEguU7FSP3tT7h10tU7QCZmVv3VQWz 3P9jA++wmEe1qRl4MmW6cB+kCHDIJVOm6KXYcujhMuT6knBHqhKSlNmGYJrFPQL06KRy T1P/te4/Q9JeLCfOxj6whZsaMQg9uK+eIFk1VXf9AF4mvFOoq/2gJarF0gL1FrBxHs8+ gh0+Uec+7Heqi/fpINwOgeIWnXXsWOPhBE1CCM0kVhAYq9EF7UlRqhDeUelARzKrEG9L 1TWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=+W9Fu950QMsufBfCCPx+AFaKU8cPICx7xAobprqzZjM=; b=IeZdBZ8lt/XulAXXFlxwzq6Ehzp9JWu4i7auM/8yQP6YCPG7R26/Fnnb/352Isx+9Q mVLiM+zi+zMctW3ipDt2EwVhoIgjDE0a6uxZhj0BLvzpU9i0OwF3BfFrVAV4aOJVWYFM R8F99dIwSCZ595vK0j4ktOL1ZgwGzRvCo7jesW0J0AtynEpVjbi5wRQ26QId+IbiQiI7 +ocW4pBt5YGsxYq17dlnZMCzwx52DceeOFPUTRDSi3DsyHUFmsnSVkdUYOcWdys2Rqzf AhyCDbv6aG0Z8c/TzKiPtVA2Rrls04Fvn+fJqw9w/g7j4EpPwWAoVmzNPWzKKtgU/evS dwXQ== X-Gm-Message-State: APjAAAVORdMOmu1m8525JdjOZlsMnmDcjB4/M5tNDqGchllGLXmXuJeF whGNT1adP//8NOYY/r4cY95w2QYPoZgaauPxYsc= X-Google-Smtp-Source: APXvYqxnrB4IiF1XWQJdXPRciWeUOMIOt0s4We1X1OrTsNZMGgvS6iWNLx4UmmepwkQUKKhdElmEUt7TKDRGSjXGvZQ= X-Received: by 2002:aa7:c49a:: with SMTP id m26mr42805347edq.0.1563468224397; Thu, 18 Jul 2019 09:43:44 -0700 (PDT) MIME-Version: 1.0 References: <20190718024133.3873-1-leonardo@linux.ibm.com> <1563430353.3077.1.camel@suse.de> <0e67afe465cbbdf6ec9b122f596910cae77bc734.camel@linux.ibm.com> <20190718155704.GD30461@dhcp22.suse.cz> <20190718164043.GE30461@dhcp22.suse.cz> In-Reply-To: <20190718164043.GE30461@dhcp22.suse.cz> From: Pavel Tatashin Date: Thu, 18 Jul 2019 12:43:33 -0400 Message-ID: Subject: Re: [PATCH 1/1] mm/memory_hotplug: Adds option to hot-add memory in ZONE_MOVABLE To: Michal Hocko Cc: Leonardo Bras , Oscar Salvador , LKML , linux-mm , Greg Kroah-Hartman , "Rafael J. Wysocki" , Andrew Morton , Mike Rapoport , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Thomas Gleixner , Pasha Tatashin , Bartlomiej Zolnierkiewicz Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Just trying to understand, if kernel parameters is the preferable > > method, why do we even have > > > > MEMORY_HOTPLUG_DEFAULT_ONLINE > > I have some opinion on this one TBH. I have even tried to remove it. The > config option has been added to workaround hotplug issues for some > memory balloning usecases where it was believed that the memory consumed > for the memory hotadd (struct pages) could get machine to OOM before > userspace manages to online it. So I would be more than happy to remove > it but there were some objections in the past. Maybe the work by Oscar > to allocate memmaps from the hotplugged memory can finally put an end to > this gross hack. Makes sense, thank you for the background info. Pasha