From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2a00:1450:4864:20::329; helo=mail-wm1-x329.google.com; envelope-from=leif.lindholm@linaro.org; receiver=edk2-devel@lists.01.org Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id F2C86211B7361 for ; Thu, 17 Jan 2019 04:08:21 -0800 (PST) Received: by mail-wm1-x329.google.com with SMTP id t200so823212wmt.0 for ; Thu, 17 Jan 2019 04:08:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ZnL7DEov/XvTuGcm4ZMNKWdxwfKetd/QrtIazjNI9Tc=; b=F4I0lzeqPs20rm3IOpA8h5oNckvquYJP9F0BGFnR1k/Zv/wSjG+L6iO80E1tfV5qP7 uWUum/4AGUuc3AxdowBAN8i/y519xaIY70tYhVD0fhbxpXKDq0jokL2g82zoYH/jA0B4 UyXYCed5PO3nPHKn8HI6xQsq5VP/hlHLbarfo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=ZnL7DEov/XvTuGcm4ZMNKWdxwfKetd/QrtIazjNI9Tc=; b=AuFpYE59p34vwr5e+wc0dieVhGEVr7jMI9gQ2pVi7dMbeCfdmMJwZOQ8lpFCxyP52x o/4qnCMQN33mB3bV4czO1PQaBP4edaEQDtISRtj53QXeYzLXqApP3DOQ1Kh/C73kf/Ir kxJM24v3maNjKS63oO4wq8Nyg7gkNavSESLBb3+zqhKTBKfCoJoMLoSAdhbGzom2gwZ4 l8IdH3NACMvVCoGL1B8DQaSmzlk+V3AX+iJluAx3w+JHLHH3D8b2AF8eNJwESH4Pc0FP cxHtKASRt/P6RglU7DHG4P/llQA1/I7OUk4divRqM/jzFxMzuB57wN6vbCVdDzbE66pO ruBQ== X-Gm-Message-State: AJcUukf1XVSre5pQo1Z8qRVnana1e/xuiD3hKEc4O5MtnSeOTSektOTJ Hfzg6gKFOeQgkUpWsbfMXIMFRnk2Ghs= X-Google-Smtp-Source: ALg8bN5K5iS9SSPJ2ieU0voo69dN7Yq3/BxGDfzQZaOJcgcG9c2WGDjw7PDFC+cndDgOJ8x+7KLYHQ== X-Received: by 2002:a1c:8d12:: with SMTP id p18mr12370103wmd.31.1547726900179; Thu, 17 Jan 2019 04:08:20 -0800 (PST) Received: from bivouac.eciton.net (bivouac.eciton.net. [2a00:1098:0:86:1000:23:0:2]) by smtp.gmail.com with ESMTPSA id u10sm66735923wrr.33.2019.01.17.04.08.19 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 17 Jan 2019 04:08:19 -0800 (PST) Date: Thu, 17 Jan 2019 12:08:17 +0000 From: Leif Lindholm To: Ard Biesheuvel Cc: "edk2-devel@lists.01.org" , Masahisa Kojima Message-ID: <20190117120817.c2kpkldlzn7zjrkg@bivouac.eciton.net> References: <20190104144336.8941-1-ard.biesheuvel@linaro.org> <20190104144336.8941-7-ard.biesheuvel@linaro.org> <20190117110456.z22z2udhnbza3liy@bivouac.eciton.net> MIME-Version: 1.0 In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Subject: Re: [PATCH edk2-platforms 6/7] Platform/DeveloperBox: add .DSC/.FDF description of MM components X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Jan 2019 12:08:22 -0000 X-List-Received-Date: Thu, 17 Jan 2019 12:08:22 -0000 X-List-Received-Date: Thu, 17 Jan 2019 12:08:22 -0000 X-List-Received-Date: Thu, 17 Jan 2019 12:08:22 -0000 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, Jan 17, 2019 at 12:10:01PM +0100, Ard Biesheuvel wrote: > > > ################################################################################ > > > # > > > @@ -294,8 +295,10 @@ [PcdsFixedAtBuild.common] > > > !endif > > > gEfiMdeModulePkgTokenSpaceGuid.PcdFirmwareRevision|$(BUILD_NUMBER) > > > > > > - gArmTokenSpaceGuid.PcdMmBufferBase|0xFFC00000 > > > - gArmTokenSpaceGuid.PcdMmBufferSize|0x00200000 > > > + gEfiSecurityPkgTokenSpaceGuid.PcdUserPhysicalPresence|TRUE > > > > So, I can see why you add this hard-wired for the purpose of testing. > > But please, add a *very* conspicuous, and strongly worded, comment > > statement preceding it. > > Well, I was talking to Peter about this the other day: according to > the spec, this setting should only matter before exit boot services, > and since this platform only supports serial and GOP consoles, one > could argue that only a physically present user could interact with it > before that time. But that also makes the Pcd pointless. > The obvious way of implementing this non-trivially on this platform is > to use a DIP switch, but that requires you to open the case to > enroll/delete the platform key. Perhaps that does not matter, and it > would in fact produce a less dangerous reference implementation. I would be totally OK with that. I would also be totally OK with a DynamicPcd settable through the UI (which is what most machines I come across have). But I would also be cool with a sufficiently evil "here be dragons" statement, pointing out that we don't care that much *on*this*specific*system* because the NOR isn't actually hw protected anyway, and this implementation is all about exercising the software stack.. / Leif