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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 255ABC63697 for ; Sat, 28 Nov 2020 12:27:32 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AFA63205CA for ; Sat, 28 Nov 2020 12:27:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CUb+qf0j"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="fIMIGrnM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AFA63205CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=NRzlLCmDwxa/x1Rxlus8oW8FEK55KW9QMhZQCnW3+5c=; b=CUb+qf0j3S9tDPXFRMKs7ORCj UYiOmeLz5fvhPkM/X6xLyXyzXVRvDP7Ypk3DQjbfbLpeYp/dbCQNZyuwIesxcMEvztFV74JQx/Egf DfPsElv8QIn0FHFUZ9i1X+AR+/zx5BvdNdNzKgaalP22mKQ1HynpvoOGNEM9I+uadDZb0K086VHIX 0JCF8JngcqK98kbynPQS2o8kxg2VuK43XotUHL+CRmk8q1Gf+BVfWAWGrH6wFTue7Lr7jZuwYsZKY kMsppGeYTvF1ZQVWJ4BUw+olidcVSRtoRk6KZ9FYWJZ2ntSwGTdT6RfDwZ6kvtCJfFw7WdW5JfbIp oosQJUb1Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kizHt-0007lb-5I; Sat, 28 Nov 2020 12:25:13 +0000 Received: from mail-lj1-x244.google.com ([2a00:1450:4864:20::244]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kizHp-0007kg-9M for linux-arm-kernel@lists.infradead.org; Sat, 28 Nov 2020 12:25:10 +0000 Received: by mail-lj1-x244.google.com with SMTP id r18so9061516ljc.2 for ; Sat, 28 Nov 2020 04:25:06 -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; bh=PYgQnFYgqUddsNplUpnQ4HvBK/TKAevGLbAhKiY2Sqc=; b=fIMIGrnMtMGMEQHKUg84oqutRK7An0A4QoghvTjaNXNAHu7IsPMzqKYeQhmZboXDzx qQeqDC1U+k4iI3d7AWDKdOWJiIFamQMdsVmZsl4gKDDRq0i+jlI8C4Fwy/7b2oMszEdS qdcTC5oxaSBXyAup0bm7F1mZ67s2RhL89iM/bf7Cf7L+4U0sK2MT1yLst3NKUcNPzTj6 VEMobKzhttO5DxKgO/Ltyzwbd8t5UfC92/w5dzLqBYxCzfxtISEof+9hd8oQzCXcyrPQ Ja125i5V6Ht+IpAD3hoXhWDOBmgqXvfqUKPyY/xXYsF0z3PGmvcngJ579HKFB2ZkcHDQ Kz+g== 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; bh=PYgQnFYgqUddsNplUpnQ4HvBK/TKAevGLbAhKiY2Sqc=; b=AYNX/w4fiiT/NmgoiTxZ7CPiSKjGv9V6pdWy2jzVqOJS4zxfsSGBGVEabBN66QDw2s ZJL/M9RrPKDfHELu7Z+d/ZwNYutj9KravJeDu0DR7kpNQQ0q5XtbbWt0ofNRBOrbJpmC noR60aHhNU/0hipONMnemQGhtXGUnvhXIi0BFncZ18QxvJa2t2G/uyW/aLUyAdThTi2O 5sLBHoRQap/TrzZ8FGeLC4y3kMhK0BNzxE+atagDMr7zmCs0cHIF8tLMBREGE6b/A2GH gPPl00b3rbREENkxjkchJRhyaPIYBa41wU4WzPwH7GGMiPgCLfZH2HwK50ZD1lG2lXlF stPA== X-Gm-Message-State: AOAM5300IgtiIU/mdspo6RYDFDTeOM5+eKDa5qeFdCNv2+t9DyAGB+Th Sb+TxY92GwjqRRA+rOWnO5rQ9w== X-Google-Smtp-Source: ABdhPJzRKZv6BWNPJR4vg7a2vtSAmL9dIGprulpJaUGZoeRquRv8tvUhN3N6eQT+f1s8ji97RQm7HQ== X-Received: by 2002:a2e:2a86:: with SMTP id q128mr5357135ljq.158.1606566305424; Sat, 28 Nov 2020 04:25:05 -0800 (PST) Received: from jade (h-249-223.A175.priv.bahnhof.se. [98.128.249.223]) by smtp.gmail.com with ESMTPSA id u25sm1315496lji.6.2020.11.28.04.25.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 28 Nov 2020 04:25:04 -0800 (PST) Date: Sat, 28 Nov 2020 13:25:02 +0100 From: Jens Wiklander To: Sudeep Holla Subject: Re: [PATCH v2 0/9] firmware: Add initial support for Arm FF-A Message-ID: <20201128122502.GA8649@jade> References: <20201103174350.991593-1-sudeep.holla@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201103174350.991593-1-sudeep.holla@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201128_072509_730387_ABD93CF4 X-CRM114-Status: GOOD ( 19.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Trilok Soni , devicetree@vger.kernel.org, David Hartley , Andrew Walbran , Achin Gupta , arve@android.com, Trilok Soni , Fuad Tabba , Android Kernel Team , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Sudeep, On Tue, Nov 03, 2020 at 05:43:41PM +0000, Sudeep Holla wrote: > Hi all, > > Let me start stating this is just initial implementation to check on > the idea of providing more in-kernel and userspace support. Lot of things > are still work in progress, I am posting just to get the early feedback > before building lot of things on this idea. Consider this more as RFC > though not tagged explicity(just to avoid it being ignored :)) > > Arm Firmware Framework for Armv8-A specification[1] describes a software > architecture that provides mechanism to utilise the virtualization > extension to isolate software images and describes interfaces that > standardize communication between the various software images. This > includes communication between images in the Secure and Normal world. > > The main idea here is to create FFA device to establish any communication > with a partition(secure or normal world VM). > > If it is a partition managed by hypervisor, then we will register chardev > associated with each of those partition FFA device. > > /dev/arm_ffa: > > e3a48fa5-dc54-4a8b-898b-bdc4dfeeb7b8 > 49f65057-d002-4ae2-b4ee-d31c7940a13d > > For in-kernel usage(mostly communication with secure partitions), only > in-kernel APIs are accessible(no userspace). There may be a need to > provide userspace access instead of in-kernel, it is not yet support > in this series as we need way to identify those and I am not sure if > that belong to DT. With unfiltered VM to VM commnication from user space there's no easy way for two VMs to exchange privileged information that excludes user space. Perhaps access to the FFA device is considered privileged and enough for all purposes. If I've understood it correctly is VM to SP communication only allowed via kernel mode in the VM. The communication with OP-TEE depends on this with the recent commit c5b4312bea5d ("tee: optee: Add support for session login client UUID generation"). Cheers, Jens _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel