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=-6.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 06B39C433E0 for ; Thu, 30 Jul 2020 20:01:24 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 C5B322074B for ; Thu, 30 Jul 2020 20:01:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=xen.org header.i=@xen.org header.b="ASlhrZb4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C5B322074B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k1EjT-0005x0-4I; Thu, 30 Jul 2020 20:00:51 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k1EjS-0005wu-2y for xen-devel@lists.xenproject.org; Thu, 30 Jul 2020 20:00:50 +0000 X-Inumbo-ID: 5c86ad53-d29f-11ea-8dc7-bc764e2007e4 Received: from mail.xenproject.org (unknown [104.130.215.37]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 5c86ad53-d29f-11ea-8dc7-bc764e2007e4; Thu, 30 Jul 2020 20:00:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=XOqBVUmSR6XbSqoKdv8Ee7IMVjkKW34Rs6RR9l/DbA0=; b=ASlhrZb4/vPTrI14J0edpJ4rPN gQupt3Wm6+qomnQ8/T36AAYCfR9H09QDwkS3v68uHdJgqBiTdhrcNyJW3lOwMOaqwmag/RdpwnbS2 vmqCQK/6qgmIsx9wnV99JKc1cLYRNMaK7DieTVHzfi0nQgpqUIyjo57yKiigaawxOXOE=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k1EjL-0001fi-E3; Thu, 30 Jul 2020 20:00:43 +0000 Received: from 54-240-197-226.amazon.com ([54.240.197.226] helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1k1EjL-0004yG-5k; Thu, 30 Jul 2020 20:00:43 +0000 Subject: Re: [PATCH 4/5] xen/memory: Fix acquire_resource size semantics To: Andrew Cooper , paul@xen.org, 'Xen-devel' References: <20200728113712.22966-1-andrew.cooper3@citrix.com> <20200728113712.22966-5-andrew.cooper3@citrix.com> <002b01d6664b$c7eb5f40$57c21dc0$@xen.org> <474ff131-83d8-deff-4e3a-32392ea092b3@citrix.com> From: Julien Grall Message-ID: <5c7d67c3-4731-caf0-cbe5-3849cd07bf98@xen.org> Date: Thu, 30 Jul 2020 21:00:40 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <474ff131-83d8-deff-4e3a-32392ea092b3@citrix.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: 'Stefano Stabellini' , 'Hubert Jasudowicz' , 'Wei Liu' , 'Konrad Rzeszutek Wilk' , 'George Dunlap' , =?UTF-8?B?J01pY2hhxYIgTGVzemN6ecWEc2tpJw==?= , 'Jan Beulich' , 'Ian Jackson' Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Hi Andrew, On 30/07/2020 20:46, Andrew Cooper wrote: > On 30/07/2020 09:31, Paul Durrant wrote: > In between these two hypercalls from the utility, the guest can do a > v1=>v2 or v2=>v1 switch and make the resource spontaneously appear or > disappear. This can only happen on platform where grant-table v2 is enabled. Where this is not enabled (e.g Arm), then I think we want to return 0 as there is nothing to map. Cheers, -- Julien Grall