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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 814C4C433DF for ; Fri, 10 Jul 2020 15:49:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 55DC820725 for ; Fri, 10 Jul 2020 15:49:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OXRoxJfs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728156AbgGJPse (ORCPT ); Fri, 10 Jul 2020 11:48:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728133AbgGJPsd (ORCPT ); Fri, 10 Jul 2020 11:48:33 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E951CC08C5CE; Fri, 10 Jul 2020 08:48:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=9AtbCOMTaB9TfwaJoiXvcEqoE4bI1Zlr762TPY5bg7c=; b=OXRoxJfsNINR7br0uKMyJjdYcl 6X48gTp/kiEodNwE1h+FcQV5JegQ7xLzmUUJMPEq042U+WEwTA9S6bK5gJCmF2vY+wZWbP9yMSeBo fDtjSM+peY/yGflCRuLRZNaEtdolGYlj6E69yMWatTZOzNcRgmXVf6P85JajST8fE8MkaybEZ8rZB GT5Gbo+Gi291k2ksp5XvmSfXd6ASZEPcWfxhgODXeM+EWAS0pDkwoYUF2rv8dfEiusfQoSiw6u1LJ wTp/mXuSsfIZkxYtR9gmS6Gv57A6SShRG+4SducoOIEIGCU4a1HG0Cxp/KzzEK0yP2hhjaa6u+H0p HfaOsmgQ==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jtvFv-0001yh-FL; Fri, 10 Jul 2020 15:48:07 +0000 Date: Fri, 10 Jul 2020 16:48:07 +0100 From: Christoph Hellwig To: Giovanni Cabiddu Cc: alex.williamson@redhat.com, herbert@gondor.apana.org.au, cohuck@redhat.com, nhorman@redhat.com, vdronov@redhat.com, bhelgaas@google.com, mark.a.chambers@intel.com, gordon.mcfadden@intel.com, ahsan.atta@intel.com, qat-linux@intel.com, kvm@vger.kernel.org, linux-crypto@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/5] vfio/pci: add blocklist and disable qat Message-ID: <20200710154807.GA7292@infradead.org> References: <20200701110302.75199-1-giovanni.cabiddu@intel.com> <20200701124209.GA12512@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200701124209.GA12512@infradead.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Jul 01, 2020 at 01:42:09PM +0100, Christoph Hellwig wrote: > On Wed, Jul 01, 2020 at 12:02:57PM +0100, Giovanni Cabiddu wrote: > > This patchset defines a blocklist of devices in the vfio-pci module and adds > > the current generation of Intel(R) QuickAssist devices to it as they are > > not designed to run in an untrusted environment. > > How can they not be safe? If any device is not safe to assign the > whole vfio concept has major issues that we need to fix for real instead > of coming up with quirk lists for specific IDs. No answer yet: how is this device able to bypass the IOMMU? Don't we have a fundamental model flaw if a random device can bypass the IOMMU protection? Except for an ATS bug I can't really think of a way how a device could bypass the IOMMU, and in that case we should just disable ATS.