From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2a00:1450:400c:c09::235; helo=mail-wm0-x235.google.com; envelope-from=leif.lindholm@linaro.org; receiver=edk2-devel@lists.01.org Received: from mail-wm0-x235.google.com (mail-wm0-x235.google.com [IPv6:2a00:1450:400c:c09::235]) (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 0CA062034D80E for ; Tue, 7 Nov 2017 03:26:37 -0800 (PST) Received: by mail-wm0-x235.google.com with SMTP id b189so2964921wmd.4 for ; Tue, 07 Nov 2017 03:30:37 -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=9R1MN8brMPfyAjZ6cKgBcQNNbf0v61eE70hmTlkl+gY=; b=PfCth2rokyMmhHUkOlpt6wM05gY+rfwVrG3aPCGDJDmvBBhN7b7i3DddToicLQjOMB R7gPpxironWMUSg8WmtEwEFqFj9ueQ1mVSaMya59eEwITYJL1aX95eKerIGCR6g9kMve 5DXeNxFwcnU9/q0XozAWcq0LVamAmSA473ZD4= 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=9R1MN8brMPfyAjZ6cKgBcQNNbf0v61eE70hmTlkl+gY=; b=fBvvanacbE3AetVBAOBzlPrfOmyzEgJ8RseIJxq0p8Mxq+l2FSmJhZsIBVe82Hd6Pq 3OJvlzveQ7yOXnfm6v6RFVW8qT6Zvzo1f8ORMnCV6Egm+J/EliVWJhAXwsgYaB4NlL7e GOOGsFMqsfmQLRoQc+y7rPHwQfOJj5+jwUuWIEjdeCJNmISS6yVSYuMjG+xXrIzZl1ae zw/vHuPEXKFjJtfMXyyHtqNoXPAqzM6/LIlIz9OC9DDzK3hW9ZJEjvA/DHbIJhdmRyh4 JCi6b6bz3nfqO5BI0sD76KPVwCqCuWVR1DKGc2wUp9flXk8X513gEj24EYGpi197e5uA oyDA== X-Gm-Message-State: AJaThX4NN2zX+yRSPGP7oB262xIxN7e/QFS8x9qXkt2YRuj+dj3+LGKV MNT1bIKXuH7bvUNQg9tLZYPfgQ== X-Google-Smtp-Source: ABhQp+ToN0OBIGlMwIKFV8g0RJpzT9eFWCKrf3EUEpGN0qp15US/zAXS634HcORmeFjfC9/G5KHrxg== X-Received: by 10.28.166.143 with SMTP id p137mr1235408wme.149.1510054236014; Tue, 07 Nov 2017 03:30:36 -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 x70sm801526wmf.0.2017.11.07.03.30.34 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 07 Nov 2017 03:30:35 -0800 (PST) Date: Tue, 7 Nov 2017 11:30:33 +0000 From: Leif Lindholm To: Ard Biesheuvel Cc: Heyi Guo , linaro-uefi , "edk2-devel@lists.01.org" , Peicong Li Message-ID: <20171107113033.kiyzdte6nhyh3nw7@bivouac.eciton.net> References: <1510052748-5564-1-git-send-email-heyi.guo@linaro.org> <20171107112326.atof7lwtgxn5s7nv@bivouac.eciton.net> MIME-Version: 1.0 In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Subject: Re: [RFC] ArmPkg/ArmMmuLib: Add new attribute WRITE_BACK_NONSHARE X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Nov 2017 11:26:38 -0000 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Nov 07, 2017 at 11:25:16AM +0000, Ard Biesheuvel wrote: > >> I'd prefer the name > >> ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK_NONSHAREABLE but other than > >> that, this looks sensible to me. Leif? > > > > And the same for NONSECURE, yes. > > With that modification, this sounds like something absolutely required > > in this situation. > > > > Does this scenario have any further implications for runtime use? > > I don't think so. These attributes are only used to select the > attributes UEFI uses for its own mapping, and they should only be used > for non-DRAM, so they shouldn't leak into the UEFI memory map in a way > the OS would be able to notice. Yes, that makes sense. Just wanted to double-check. / Leif