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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 8AE14C43381 for ; Fri, 22 Feb 2019 21:50:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 613E9206DD for ; Fri, 22 Feb 2019 21:50:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725814AbfBVVuJ (ORCPT ); Fri, 22 Feb 2019 16:50:09 -0500 Received: from mga12.intel.com ([192.55.52.136]:20413 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725811AbfBVVuJ (ORCPT ); Fri, 22 Feb 2019 16:50:09 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Feb 2019 13:50:05 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,401,1544515200"; d="scan'208";a="124503361" Received: from delmer-mobl.ger.corp.intel.com (HELO localhost) ([10.249.254.153]) by fmsmga007.fm.intel.com with ESMTP; 22 Feb 2019 13:50:00 -0800 Date: Fri, 22 Feb 2019 23:50:01 +0200 From: Jarkko Sakkinen To: "Michael S. Tsirkin" Cc: David Tolnay , Peter Huewe , Jason Gunthorpe , linux-integrity@vger.kernel.org, Jason Wang , virtualization@lists.linux-foundation.org, dgreid@chromium.org, apronin@chromium.org Subject: Re: [PATCH] tpm: Add driver for TPM over virtio Message-ID: <20190222215001.GA21427@linux.intel.com> References: <388c5b80-21a7-1e91-a11f-3a1c1432368b@gmail.com> <20190222102610.GB5613@linux.intel.com> <20190222101728-mutt-send-email-mst@kernel.org> <20190222193156.GA6475@linux.intel.com> <20190222193305.GB6475@linux.intel.com> <20190222161636-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190222161636-mutt-send-email-mst@kernel.org> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Fri, Feb 22, 2019 at 04:25:08PM -0500, Michael S. Tsirkin wrote: > On Fri, Feb 22, 2019 at 09:33:05PM +0200, Jarkko Sakkinen wrote: > > On Fri, Feb 22, 2019 at 09:31:56PM +0200, Jarkko Sakkinen wrote: > > > On Fri, Feb 22, 2019 at 10:23:02AM -0500, Michael S. Tsirkin wrote: > > > > On Fri, Feb 22, 2019 at 12:26:10PM +0200, Jarkko Sakkinen wrote: > > > > > On Thu, Feb 21, 2019 at 06:14:02PM -0800, David Tolnay wrote: > > > > > > Add a config TCG_VIRTIO_VTPM which enables a driver providing the guest > > > > > > kernel side of TPM over virtio. > > > > > > > > > > > > Use case: TPM support is needed for performing trusted work from within > > > > > > a virtual machine launched by Chrome OS. > > > > > > > > > > > > Tested inside crosvm, the Chrome OS virtual machine monitor. Crosvm's > > > > > > implementation of the virtio TPM device can be found in these two source > > > > > > files: > > > > > > > > > > > > - https://chromium.googlesource.com/chromiumos/platform/crosvm/+/18ce5713e6cb99c40aafec52b67c28ba12a44f31/devices/src/virtio/tpm.rs > > > > > > - https://chromium.googlesource.com/chromiumos/platform/crosvm/+/18ce5713e6cb99c40aafec52b67c28ba12a44f31/tpm2/src/lib.rs > > > > > > > > > > These files/links do not make sense for kernel testing. Please remove > > > > > them from the next version. > > > > > > > > To clarify generally for a virtio device we want > > > > - guest support > > > > - device support > > > > - spec > > > > > > > > If the device is implemented in qemu and guest in linux kernel, > > > > then there are lots of people familiar with these > > > > programming environments, so sometimes we merge > > > > guest and host code even if spec isn't written up at all. > > > > > > > > If you don't want to do that there's a small number of people who can > > > > properly review code, e.g. I don't think lots of people on this list are > > > > familiar with crosvm. One way to address this would be to build a QEMU > > > > implementation. Another would be to write up a spec. You can do both > > > > too :) > > > > > > I don't really understand your arguments. > > > > ... and I did your response total three times and did not find any > > causality of any sort from anything. > > > > /Jarkko > > Thanks for spending the time reading my response. What was included in > it was a general suggestion for a virtio based driver to be acceptable > in upstream Linux. > > You pointed out that a pointer to a prototype implementation in Rust > isn't relevant. However, FYI just posting guest code and asking for it > to be merged alone won't work for a virtio driver either. I am merely > trying to speed things up instead of having the contributor repost with > a tweaked commit log just to immediately get another set of nacks. I did not say anything about relevance of any implementation. I tried to mainly point out that looking at random source files implemented with a relatively alien language to most does not really make a case. Things that would help to move this forward: - Documentation of the stack, nothing spectacular but more like how it works in practical terms. - Sufficiently easy ways to test the code. - Explain in the commit message why we want this. /Jarkko