From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f50.google.com (mail-lf1-f50.google.com [209.85.167.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6C92364D for ; Wed, 14 Feb 2024 08:34:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707899695; cv=none; b=dfHpE5agKPkydoyHWWoQgZfqs5ZyJDv+QurIbddEjJm1cydXQ4cxQMZj1JtuxSk4ccrdJ7HQojLMUjS6LkoXGEVz20cqi2alJs5AC8dL81JjiQt02FECIgqdTIl1AP3LeKoqM37PBxxJFhHjJaKcoBB36KJpABUFb8MzP/QksN4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707899695; c=relaxed/simple; bh=PFn4wCJ4Kc9o4ZUF1udSybUYlNbwYhG9hFxqj59fXaM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=DkSVcEdqbLIqKMojWxGJbuTW3AoN4qzO+ptYSq6MSpp3T9/5O7+Oc2Dc05IqPpjzR+uxzxHuN6MD4QhtsCZGqJ/g6tZinpDLxbS5uqAI0oQk7w0ON/xRhCwdj3RavDMuUyhWgqnGcj0XBQEqgck/K/D2BSGd01SZM9UrfE0gDbQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=XzfrNNr1; arc=none smtp.client-ip=209.85.167.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="XzfrNNr1" Received: by mail-lf1-f50.google.com with SMTP id 2adb3069b0e04-511976c126dso2345449e87.1 for ; Wed, 14 Feb 2024 00:34:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1707899691; x=1708504491; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=uAiL2qOT91a69hH8+cvQmScbp9QK6BB+OUyGeu3FPlA=; b=XzfrNNr1BA93ARo8mkAC9sVjYAr6liasUZtDjSZx/f7gFs5RB9ckuqQDGoSjRYviWe l0s/bQniZhHkDMtPAubE1iAv2Tdq298I0FQ4HWa1EE9doRRtRCK0Itr7tipAY5THpFTh kSQqWJl63n3KYYkMAkUPe34JmEiqM/WxOFR5z4rV78s8UK2S/L6Ssuv1p+bEYbtfTeOC 2+QxCuQNMY3F7TZWKDQ+FOpMlQAMCYa0w4Y94XTHzOv+xb6RXoPyzZxJDIhL/plGgzjd EaULKFrtteqh5gBE+fLUNMYgunjf5lbgs1EwLB+6C62qPoB4cclGOW1ZTrO5NFKb/Fm2 YFvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707899691; x=1708504491; 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=uAiL2qOT91a69hH8+cvQmScbp9QK6BB+OUyGeu3FPlA=; b=vCWp6mzrQDkFJgPmIQvNkjoN7fsDX3APPqYXH1b7MkI0zAJP2fRsIThbfwHot2qarZ yaVeD3eI9kcIXuREP1ZhWpLJrE0v3ME5iXZAhFpZ9vzCT2wRYh6zZtPkweENaX5J2ZQT mLE6DHd5SjO1wr1wW290g/69saLh3EOxdW67Opmvc0nG4UqyNoG7onI/5Pa10aSw/Z22 W4XGuo7JzJX9Xzi9zp9GCVXo1o7B175UxhLFwReajVTvx2/JiIVTZB3Iki5xLknz0RqP TN2Hp72h4jhkm5GwGw5IUrPHKUE3amegYfpobgqkyvSjZHHjd3Jxtu9s8OQ/z1bA59x+ umVQ== X-Forwarded-Encrypted: i=1; AJvYcCWTJ83rwJcVbRuHsN2xt3yKyv9UVtoGpmXv8UjXS3UUtQFs2YJXFhBvgC/Gm7oZ1fu+zmmmPH1g7Nqz1P0qgGwMnyQyEHtsVBykTKsw X-Gm-Message-State: AOJu0YzyCDXj1EYQL6F63+HdeSpWkRVpdhPpxm3Ae1OpR2+lEpieJzV1 6kWifNUqL9hRVzr1cJkowuprfppOXyB+K2cfkt92UB1Ie8azpMwfnZjj9QNM0Gg= X-Google-Smtp-Source: AGHT+IGNZP5/YY1RfF2lKO9BAAKxQ2ruwwCntxr2AxjDChypk993E72C6C2Q1/RyRnrut17odI30UA== X-Received: by 2002:ac2:5b4c:0:b0:511:483b:91c6 with SMTP id i12-20020ac25b4c000000b00511483b91c6mr1203488lfp.48.1707899691455; Wed, 14 Feb 2024 00:34:51 -0800 (PST) X-Forwarded-Encrypted: i=1; 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 Received: from [192.168.0.20] (nborisov.ddns.nbis.net. [85.187.217.136]) by smtp.gmail.com with ESMTPSA id s1-20020a056512214100b005115dc3a63fsm1598800lfr.135.2024.02.14.00.34.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 14 Feb 2024 00:34:51 -0800 (PST) Message-ID: Date: Wed, 14 Feb 2024 10:34:48 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] x86/random: Retry on RDSEED failure Content-Language: en-US To: Theodore Ts'o , Dan Williams Cc: "Reshetova, Elena" , "Jason A. Donenfeld" , "Kirill A. Shutemov" , "H. Peter Anvin" , Dave Hansen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "x86@kernel.org" , Kuppuswamy Sathyanarayanan , "Nakajima, Jun" , Tom Lendacky , "Kalra, Ashish" , Sean Christopherson , "linux-coco@lists.linux.dev" , "linux-kernel@vger.kernel.org" References: <20240202153927.GA119530@mit.edu> <20240212163236.GA444708@mit.edu> <65cb1a1fe2dda_29b1294e@dwillia2-mobl3.amr.corp.intel.com.notmuch> <20240213231341.GB394352@mit.edu> <65cc0ef2c7be_29b12948d@dwillia2-mobl3.amr.corp.intel.com.notmuch> <20240214043245.GC394352@mit.edu> From: Nikolay Borisov In-Reply-To: <20240214043245.GC394352@mit.edu> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 14.02.24 г. 6:32 ч., Theodore Ts'o wrote: > On Tue, Feb 13, 2024 at 04:53:06PM -0800, Dan Williams wrote: >> >> Indeed it is. Typically when you have x86, riscv, arm, and s390 folks >> all show up at a Linux Plumbers session [1] to talk about their approach >> to handling a new platform paradigm, that is a decent indication that >> the technology is more real than not. Point taken that it is not here >> today, but it is also not multiple hardware generations away as the >> Plumbers participation indicated. > > My big concerns with TDISP which make me believe it may not be a > silver bullet is that (a) it's hyper-complex (although to be fair > Confidential Compute isn't exactly simple, and (b) it's one thing to > digitally sign software so you know that it comes from a trusted > source; but it's a **lot** harder to prove that hardware hasn't been > tampered with --- a digital siganture can't tell you much about > whether or not the hardware is in an as-built state coming from the > factory --- this requires things like wrapping the device with > resistive wire in multiple directions with a whetstone bridge to > detect if the wire has gotten cut or shorted, then dunking the whole > thing in epoxy, so that any attempt to tamper with the hardware will > result it self-destructing (via a thermite charge or equivalent :-) This really reminds me of the engineering that goes into the omnipresent POS terminals ate every store, since they store certificates from the card (Visa/Master) operators. So I wonder if at somepoint we'll have a pos-like device (by merit of its engineering) in every server.... > > Remember, the whole conceit of Confidential Compute is that you don't > trust the cloud provider --- but if that entity controls the PCI cards > installed in their servers, and and that entity has the ability to > *modify* the PCI cards in the server, all of the digital signatures > and fancy-schmancy TDISP complexity isn't necessarily going to save > you. Can't the same argument go for the CPU, though it's a lot more "integrated" into the silicong substrate, yet we somehow believe CoCo ascertains that a vm is running on trusted hardware? But ultimately the CPU is still a part that comes from the untrusted CSP.