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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 2170DC31E43 for ; Mon, 10 Jun 2019 16:56:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 005D42086A for ; Mon, 10 Jun 2019 16:56:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728370AbfFJQ4t (ORCPT ); Mon, 10 Jun 2019 12:56:49 -0400 Received: from mx2.suse.de ([195.135.220.15]:57588 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727648AbfFJQ4s (ORCPT ); Mon, 10 Jun 2019 12:56:48 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id C303FAC3A; Mon, 10 Jun 2019 16:56:46 +0000 (UTC) Date: Mon, 10 Jun 2019 18:56:43 +0200 From: Oscar Salvador To: David Hildenbrand Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, Dan Williams , Wei Yang , Igor Mammedov , Greg Kroah-Hartman , "Rafael J. Wysocki" , Alex Deucher , "David S. Miller" , Mark Brown , Chris Wilson , Jonathan Cameron Subject: Re: [PATCH v3 10/11] mm/memory_hotplug: Make unregister_memory_block_under_nodes() never fail Message-ID: <20190610165642.GB5643@linux> References: <20190527111152.16324-1-david@redhat.com> <20190527111152.16324-11-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190527111152.16324-11-david@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 27, 2019 at 01:11:51PM +0200, David Hildenbrand wrote: > We really don't want anything during memory hotunplug to fail. > We always pass a valid memory block device, that check can go. Avoid > allocating memory and eventually failing. As we are always called under > lock, we can use a static piece of memory. This avoids having to put > the structure onto the stack, having to guess about the stack size > of callers. > > Patch inspired by a patch from Oscar Salvador. > > In the future, there might be no need to iterate over nodes at all. > mem->nid should tell us exactly what to remove. Memory block devices > with mixed nodes (added during boot) should properly fenced off and never > removed. > > Cc: Greg Kroah-Hartman > Cc: "Rafael J. Wysocki" > Cc: Alex Deucher > Cc: "David S. Miller" > Cc: Mark Brown > Cc: Chris Wilson > Cc: David Hildenbrand > Cc: Oscar Salvador > Cc: Andrew Morton > Cc: Jonathan Cameron > Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador -- Oscar Salvador SUSE L3