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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14C60C43334 for ; Mon, 25 Jul 2022 19:27:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230348AbiGYT1L (ORCPT ); Mon, 25 Jul 2022 15:27:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229908AbiGYT1K (ORCPT ); Mon, 25 Jul 2022 15:27:10 -0400 Received: from mail-oi1-f182.google.com (mail-oi1-f182.google.com [209.85.167.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA7E0A45A; Mon, 25 Jul 2022 12:27:08 -0700 (PDT) Received: by mail-oi1-f182.google.com with SMTP id bb16so14655316oib.11; Mon, 25 Jul 2022 12:27:08 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=biplv8ZnovJJIoreJcaFobXzSk+jEJJVI0kZQA2bmqY=; b=uqu+6HMtKu11PhWQkaU8nbwJVlQTV/9vlUq1cXkrYdZOPv8bLGAH+0AD+SE0zxCgS/ C/CaT5IbrfRsC6D8JiDcJzs0f/rQNvtrKpd+j3eG0O97cr/p9ls0Ni9SvEfTEJcv4XPj zH7HK5wKq7lquBgvUeFNCnHmJa4zBv0zD4qRE2tGCE12N+HqlduAGkXnBleTofD3cqPW 7u+CfBeNaNUs7OvLtnBCyEt2atwaJhEamm6eOinbeC/hCt/+QeZJn3FyuXbjcdqG9//O vL9+l0+Nhp7GkWNBTg/XRnEENZsFYWc1Nlz1C/qiHbK8RmM1B96DfnoSZCrAxHqJG6D/ L2zQ== X-Gm-Message-State: AJIora92tBFTEYVrCiRcTFP4s0R/xiL0ejRElC/MjsBUfCxOq2S7l/Bu yLSFyMQfUDkhivB9s+xzvw== X-Google-Smtp-Source: AGRyM1sHRDiIqGa4CnHexl48xYWTF6EUArhGrzGDOK0Z9M8NJdDZGNdX/YvkELxDpJNw/dF1MbyF6A== X-Received: by 2002:a05:6808:1a88:b0:33a:a573:c1a0 with SMTP id bm8-20020a0568081a8800b0033aa573c1a0mr11389536oib.222.1658777228095; Mon, 25 Jul 2022 12:27:08 -0700 (PDT) Received: from robh.at.kernel.org ([64.188.179.248]) by smtp.gmail.com with ESMTPSA id w7-20020a4aca07000000b0041ba304546csm5176012ooq.1.2022.07.25.12.27.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jul 2022 12:27:07 -0700 (PDT) Received: (nullmailer pid 2550854 invoked by uid 1000); Mon, 25 Jul 2022 19:27:05 -0000 Date: Mon, 25 Jul 2022 13:27:05 -0600 From: Rob Herring To: Maximilian Luz Cc: Andy Gross , Bjorn Andersson , Ard Biesheuvel , Konrad Dybcio , Krzysztof Kozlowski , Steev Klimaszewski , Shawn Guo , Sudeep Holla , Cristian Marussi , Greg Kroah-Hartman , linux-arm-msm@vger.kernel.org, linux-efi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4] firmware: Add support for Qualcomm UEFI Secure Application Message-ID: <20220725192705.GA2536409-robh@kernel.org> References: <20220723224949.1089973-1-luzmaximilian@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220723224949.1089973-1-luzmaximilian@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Sun, Jul 24, 2022 at 12:49:45AM +0200, Maximilian Luz wrote: > On modern Qualcomm platforms, access to EFI variables is restricted to > the secure world / TrustZone, i.e. the Trusted Execution Environment > (TrEE or TEE) as Qualcomm seems to call it. To access EFI variables, we > therefore need to talk to the UEFI Secure Application (uefisecapp), > residing in the TrEE. The whole point of UEFI is providing a standard interface. Why can't the UEFI implementation call the TEE itself? I'm not sure custom interfaces is something we want. > This series adds support for accessing EFI variables on those platforms. > > To do this, we first need to add some SCM call functions used to manage > and talk to Secure Applications. A very small subset of this interface > is added in the second patch (whereas the first one exports the required > functions for that). Interface specifications are extracted from [1]. > While this does not (yet) support re-entrant SCM calls (including > callbacks and listeners), this is enough to talk to the aforementioned > uefisecapp on a couple of platforms (I've tested this on a Surface Pro X > and heard reports from Lenovo Flex 5G, Lenovo Thinkpad x13s, and Lenovo > Yoga C630 devices). What does Windows do on these devices? I'm surprised something like this would fly with Microsoft. Rob