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=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 4DFA3C433DB for ; Wed, 3 Feb 2021 12:49:38 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 BFFE264DE7 for ; Wed, 3 Feb 2021 12:49:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BFFE264DE7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id A2E5A85124; Wed, 3 Feb 2021 12:49:37 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id w_5EYzWcRMVX; Wed, 3 Feb 2021 12:49:33 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 3EC2885010; Wed, 3 Feb 2021 12:49:33 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 0EA83C1DA7; Wed, 3 Feb 2021 12:49:33 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7E26BC0174; Wed, 3 Feb 2021 12:49:31 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 6579F8653F; Wed, 3 Feb 2021 12:49:31 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id XI9JYc3xxmOl; Wed, 3 Feb 2021 12:49:28 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by hemlock.osuosl.org (Postfix) with ESMTPS id 2A33485A82; Wed, 3 Feb 2021 12:49:27 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 3E31267357; Wed, 3 Feb 2021 13:49:23 +0100 (CET) Date: Wed, 3 Feb 2021 13:49:22 +0100 From: Christoph Hellwig To: Martin Radev Subject: Re: [PATCH] swiotlb: Validate bounce size in the sync/unmap path Message-ID: <20210203124922.GB16923@lst.de> References: <20210113113017.GA28106@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: thomas.lendacky@amd.com, file@sect.tu-berlin.de, robert.buhren@sect.tu-berlin.de, kvm@vger.kernel.org, konrad.wilk@oracle.com, mathias.morbitzer@aisec.fraunhofer.de, joro@8bytes.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, iommu@lists.linux-foundation.org, robin.murphy@arm.com, Christoph Hellwig , kirill.shutemov@linux.intel.com, m.szyprowski@samsung.com X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Mon, Jan 18, 2021 at 12:44:58PM +0100, Martin Radev wrote: > Your comment makes sense but then that would require the cooperation > of these vendors and the cloud providers to agree on something meaningful. > I am also not sure whether the end result would be better than hardening > this interface to catch corruption. There is already some validation in > unmap path anyway. So what? If you guys want to provide a new capability you'll have to do work. And designing a new protocol based around the fact that the hardware/hypervisor is not trusted and a copy is always required makes a lot of more sense than throwing in band aids all over the place. _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization