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=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 E3C42C71156 for ; Wed, 2 Dec 2020 06:44:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AA0722203 for ; Wed, 2 Dec 2020 06:44:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728652AbgLBGo6 (ORCPT ); Wed, 2 Dec 2020 01:44:58 -0500 Received: from foss.arm.com ([217.140.110.172]:59208 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728212AbgLBGo6 (ORCPT ); Wed, 2 Dec 2020 01:44:58 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7D93530E; Tue, 1 Dec 2020 22:44:12 -0800 (PST) Received: from [10.163.83.48] (unknown [10.163.83.48]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F3E8B3F718; Tue, 1 Dec 2020 22:44:07 -0800 (PST) Subject: Re: [RFC V2 0/3] mm/hotplug: Pre-validate the address range with platform To: linux-mm@kvack.org, akpm@linux-foundation.org, david@redhat.com Cc: linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Heiko Carstens , Vasily Gorbik , Catalin Marinas , Will Deacon , Ard Biesheuvel , Mark Rutland References: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> From: Anshuman Khandual Message-ID: <7ffb5199-1b39-3f35-32cd-b59f71cc00c5@arm.com> Date: Wed, 2 Dec 2020 12:14:04 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/30/20 8:59 AM, Anshuman Khandual wrote: > This series adds a mechanism allowing platforms to weigh in and prevalidate > incoming address range before proceeding further with the memory hotplug. > This helps prevent potential platform errors for the given address range, > down the hotplug call chain, which inevitably fails the hotplug itself. > > This mechanism was suggested by David Hildenbrand during another discussion > with respect to a memory hotplug fix on arm64 platform. > > https://lore.kernel.org/linux-arm-kernel/1600332402-30123-1-git-send-email-anshuman.khandual@arm.com/ > > This mechanism focuses on the addressibility aspect and not [sub] section > alignment aspect. Hence check_hotplug_memory_range() and check_pfn_span() > have been left unchanged. Wondering if all these can still be unified in > an expanded memhp_range_allowed() check, that can be called from multiple > memory hot add and remove paths. > > This series applies on v5.10-rc6 and has been slightly tested on arm64. > But looking for some early feedback here. > > Changes in RFC V2: > > Incorporated all review feedbacks from David. > > - Added additional range check in __segment_load() on s390 which was lost > - Changed is_private init in pagemap_range() > - Moved the framework into mm/memory_hotplug.c > - Made arch_get_addressable_range() a __weak function > - Renamed arch_get_addressable_range() as arch_get_mappable_range() > - Callback arch_get_mappable_range() only handles range requiring linear mapping > - Merged multiple memhp_range_allowed() checks in register_memory_resource() > - Replaced WARN() with pr_warn() in memhp_range_allowed() > - Replaced error return code ERANGE with E2BIG There is one build failure with MEMORY_HOTPLUG=y and MEMORY_HOTREMOVE=n. There are warnings on arm64 and s390 platforms when built with W=1 due to lack of prototypes required with -Wmissing-prototypes. I have fixed all these problems for the next iteration when there is broad agreement on the overall approach. 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=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 D537CC64E7C for ; Wed, 2 Dec 2020 06:45:39 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1C06120C56 for ; Wed, 2 Dec 2020 06:45:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C06120C56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XpnhfqZqRM5fCFpUSmM0JLut/A4sNDLeCBUFBFC844Q=; b=Uxyn3s4hVuWDB5oOSkhRviIYZ kMt83uveiiLyPCvyTPZm+A5SSrnQPixSXEY1TxC6h61W1qkgxUxU5zaN0XuEjsywzFX4QMtk2u9xV cCZJ8R9QXFk5k0iXpxutG9OTwOtbMfuTZmbvlF2QSZPiJdk4eBi2oOWakzDPOLPhcSnIKbKL7MC5J ZLGiz0yepsTuMckKOkyA2Zlo6neh2vZ4kw1h1ekzFqaID8ShcQ/v7ZMDX+pLiWmPb9EYk/ew3B1H5 ri+XXFiSk7CHRdhExZ1fXm44rztyyvPgoa42YlhaZGPIZoTAAQdK+Yo+li8RIan7A7KsRmPViaefW ZlbvBEy5A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kkLs9-0000ex-Uk; Wed, 02 Dec 2020 06:44:17 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kkLs7-0000eT-NB for linux-arm-kernel@lists.infradead.org; Wed, 02 Dec 2020 06:44:16 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7D93530E; Tue, 1 Dec 2020 22:44:12 -0800 (PST) Received: from [10.163.83.48] (unknown [10.163.83.48]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F3E8B3F718; Tue, 1 Dec 2020 22:44:07 -0800 (PST) Subject: Re: [RFC V2 0/3] mm/hotplug: Pre-validate the address range with platform To: linux-mm@kvack.org, akpm@linux-foundation.org, david@redhat.com References: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> From: Anshuman Khandual Message-ID: <7ffb5199-1b39-3f35-32cd-b59f71cc00c5@arm.com> Date: Wed, 2 Dec 2020 12:14:04 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1606706992-26656-1-git-send-email-anshuman.khandual@arm.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201202_014415_812524_8B17F9F6 X-CRM114-Status: GOOD ( 17.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-s390@vger.kernel.org, Vasily Gorbik , Catalin Marinas , Heiko Carstens , linux-kernel@vger.kernel.org, Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 11/30/20 8:59 AM, Anshuman Khandual wrote: > This series adds a mechanism allowing platforms to weigh in and prevalidate > incoming address range before proceeding further with the memory hotplug. > This helps prevent potential platform errors for the given address range, > down the hotplug call chain, which inevitably fails the hotplug itself. > > This mechanism was suggested by David Hildenbrand during another discussion > with respect to a memory hotplug fix on arm64 platform. > > https://lore.kernel.org/linux-arm-kernel/1600332402-30123-1-git-send-email-anshuman.khandual@arm.com/ > > This mechanism focuses on the addressibility aspect and not [sub] section > alignment aspect. Hence check_hotplug_memory_range() and check_pfn_span() > have been left unchanged. Wondering if all these can still be unified in > an expanded memhp_range_allowed() check, that can be called from multiple > memory hot add and remove paths. > > This series applies on v5.10-rc6 and has been slightly tested on arm64. > But looking for some early feedback here. > > Changes in RFC V2: > > Incorporated all review feedbacks from David. > > - Added additional range check in __segment_load() on s390 which was lost > - Changed is_private init in pagemap_range() > - Moved the framework into mm/memory_hotplug.c > - Made arch_get_addressable_range() a __weak function > - Renamed arch_get_addressable_range() as arch_get_mappable_range() > - Callback arch_get_mappable_range() only handles range requiring linear mapping > - Merged multiple memhp_range_allowed() checks in register_memory_resource() > - Replaced WARN() with pr_warn() in memhp_range_allowed() > - Replaced error return code ERANGE with E2BIG There is one build failure with MEMORY_HOTPLUG=y and MEMORY_HOTREMOVE=n. There are warnings on arm64 and s390 platforms when built with W=1 due to lack of prototypes required with -Wmissing-prototypes. I have fixed all these problems for the next iteration when there is broad agreement on the overall approach. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel