From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E48807E for ; Thu, 2 Feb 2023 03:25:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675308307; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iY/OQt8yhAuJl9finL5LdlRPRN18tAZGyT7vixhBhhY=; b=b/lVZWi8a46dtG933oYfXgagNj3B+kfQNgGzvkKc9ezf0Y/rzaOOoYyNrhgNc5Cwmvihdz NsiCGyPB43vuhZa3eycz2P3gdgGXpCYkFkmGs/jT/cLd1mGp6ysF07PpukIr9XFzR0g76k 8w3vJldvgdIRJzLsHk8pHBBPwG2q2yM= Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-596-7s_YBtlzOFiFIpzY3ibhOQ-1; Wed, 01 Feb 2023 22:25:03 -0500 X-MC-Unique: 7s_YBtlzOFiFIpzY3ibhOQ-1 Received: by mail-pf1-f197.google.com with SMTP id i15-20020aa787cf000000b00593addd14a5so271048pfo.15 for ; Wed, 01 Feb 2023 19:25:03 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iY/OQt8yhAuJl9finL5LdlRPRN18tAZGyT7vixhBhhY=; b=7QO3O9ODKxPHk9zNOVHB5fRhapBFWoUerA19d68IGFHByFAtokVZTbtFDKtSdaz54h byBsGa87PbkdetCgROZepfoBOB5fKAaCO35G3/9FcMzLS195BqYRTRAkRJmArrkYtEJk 5GTV7hwv8YLX2hz+doic1mKcExYA/vSK9g5qxzL98rP9mv7spKTRtiYGN2lqbqTCUtGm xD+ie0VK1Ju5X9tGLmpMxXY2bu8jvrTJnbY2RVHLfvuVxYx4g96LA7U23XJT9FajgLQY xm25aZrxduYiE7x8GFV5ZMu8yHX9LB+8cBrexMoKNbP6uQOAt1HjdTxSZ/Omwl2OwKwG mqAA== X-Gm-Message-State: AO0yUKWZop8jkk0eBe96orrpr7PrcX970LEo6xMNCWK0ie8gK0+vtS2z +R3CRY6kXaltOg3hPrE5Qfh235NFU0GjRqZPwKaQdNKzvnyS5JStzVjRmGEvjHoomvaPb649B4e cOZxFQAb/1LrLtMWCT6ScKA== X-Received: by 2002:a17:902:ecd0:b0:196:8445:56be with SMTP id a16-20020a170902ecd000b00196844556bemr5788459plh.42.1675308302892; Wed, 01 Feb 2023 19:25:02 -0800 (PST) X-Google-Smtp-Source: AK7set/pvefWS1/CpqW1NscmlurIGYYGDzwh8/dBgY5gfye1noE+4RvwU+vANRnhJEPiWLcmieADdw== X-Received: by 2002:a17:902:ecd0:b0:196:8445:56be with SMTP id a16-20020a170902ecd000b00196844556bemr5788421plh.42.1675308302560; Wed, 01 Feb 2023 19:25:02 -0800 (PST) Received: from [10.72.14.0] ([43.228.180.230]) by smtp.gmail.com with ESMTPSA id x5-20020a1709027c0500b00198b0fd363bsm2034171pll.45.2023.02.01.19.24.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 01 Feb 2023 19:25:02 -0800 (PST) Message-ID: Date: Thu, 2 Feb 2023 11:24:51 +0800 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.6.1 Subject: Re: Linux guest kernel threat model for Confidential Computing To: "Michael S. Tsirkin" , Christophe de Dinechin Dupont de Dinechin Cc: Christophe de Dinechin , James Bottomley , "Reshetova, Elena" , Leon Romanovsky , Greg Kroah-Hartman , "Shishkin, Alexander" , "Shutemov, Kirill" , "Kuppuswamy, Sathyanarayanan" , "Kleen, Andi" , "Hansen, Dave" , Thomas Gleixner , Peter Zijlstra , "Wunner, Lukas" , Mika Westerberg , "Poimboe, Josh" , "aarcange@redhat.com" , Cfir Cohen , Marc Orr , "jbachmann@google.com" , "pgonda@google.com" , "keescook@chromium.org" , James Morris , Michael Kelley , "Lange, Jon" , "linux-coco@lists.linux.dev" , Linux Kernel Mailing List , Kernel Hardening References: <702f22df28e628d41babcf670c909f1fa1bb3c0c.camel@linux.ibm.com> <220b0be95a8c733f0a6eeddc08e37977ee21d518.camel@linux.ibm.com> <261bc99edc43990eecb1aac4fe8005cedc495c20.camel@linux.ibm.com> <20230131123033-mutt-send-email-mst@kernel.org> <6BCC3285-ACA3-4E38-8811-1A91C9F03852@redhat.com> <20230201055412-mutt-send-email-mst@kernel.org> From: Jason Wang In-Reply-To: <20230201055412-mutt-send-email-mst@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 在 2023/2/1 19:01, Michael S. Tsirkin 写道: > On Wed, Feb 01, 2023 at 11:52:27AM +0100, Christophe de Dinechin Dupont de Dinechin wrote: >> >>> On 31 Jan 2023, at 18:39, Michael S. Tsirkin wrote: >>> >>> On Tue, Jan 31, 2023 at 04:14:29PM +0100, Christophe de Dinechin wrote: >>>> Finally, security considerations that apply irrespective of whether the >>>> platform is confidential or not are also outside of the scope of this >>>> document. This includes topics ranging from timing attacks to social >>>> engineering. >>> Why are timing attacks by hypervisor on the guest out of scope? >> Good point. >> >> I was thinking that mitigation against timing attacks is the same >> irrespective of the source of the attack. However, because the HV >> controls CPU time allocation, there are presumably attacks that >> are made much easier through the HV. Those should be listed. > Not just that, also because it can and does emulate some devices. > For example, are disk encryption systems protected against timing of > disk accesses? > This is why some people keep saying "forget about emulated devices, require > passthrough, include devices in the trust zone". One problem is that the device could be yet another emulated one that is running in the SmartNIC/DPU itself. Thanks