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=-5.6 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,URIBL_BLOCKED,USER_AGENT_SANE_2 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 97571C47083 for ; Thu, 3 Jun 2021 00:21:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 54B1961090 for ; Thu, 3 Jun 2021 00:21:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54B1961090 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com 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=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc: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=bCS6PO159fiIF1ST8Jw7nTqixMT1JpFmWHms/iW8H9U=; b=xP77gcUSTjL2uQ 2r9wqdW5fye8RZXIi+rmjVTYFofmyvn8cQiocooY8qd6/0/TZpH+D+3o77hEVOCtj6I/4mPaNOGL0 B9h1t1HRU0AS5yQGhRz8jbI5l6zrsRx8xUioTACvVfheJ+Sj2ZUfELHIz1S333b9vRKHrMP0bOtms dyZ2nhZa+gwD7MFnZx/WFTSX950e3aOc79XgHiuPd8HPrNWgjd3Pni3m7tcvuG3lFkmyAiiBxZxLD GqTbUWKrQXdYS+WeIWsvYG4z23cPKetk45NdWc2n1mYLvSXOveoBJB6RhvwRhXQcn4+pSRSfTv83x LxpdffpawajPdZxO0Bww==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lob5i-006b40-Ej; Thu, 03 Jun 2021 00:20:06 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lob5e-006b2z-B1 for linux-arm-kernel@lists.infradead.org; Thu, 03 Jun 2021 00:20:04 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3715F11FB; Wed, 2 Jun 2021 17:19:55 -0700 (PDT) Received: from slackpad.fritz.box (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 359A43F774; Wed, 2 Jun 2021 17:19:54 -0700 (PDT) Date: Thu, 3 Jun 2021 01:19:22 +0100 From: Andre Przywara To: Benjamin Herrenschmidt Cc: Ard Biesheuvel , Mark Brown , Will Deacon , "Saidi, Ali" , Linux ARM Subject: Re: RNDR/SS vs. SMCCC Message-ID: <20210603011922.1d0e9249@slackpad.fritz.box> In-Reply-To: <2ae9253c6f5753c13a7ed755ab0c67316c06d9b0.camel@kernel.crashing.org> References: <7d5697f3994fc1f9cf39d332525269056e3649b3.camel@kernel.crashing.org> <0339748b54e2faeddeec8d50e32a6c6ff4e8b3b7.camel@kernel.crashing.org> <20210531020235.6e4ea946@slackpad.fritz.box> <2ae9253c6f5753c13a7ed755ab0c67316c06d9b0.camel@kernel.crashing.org> Organization: Arm Ltd. X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.31; x86_64-slackware-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210602_172002_498177_6370FD11 X-CRM114-Status: GOOD ( 15.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 On Thu, 03 Jun 2021 08:04:43 +1000 Benjamin Herrenschmidt wrote: > On Mon, 2021-05-31 at 07:24 +0200, Ard Biesheuvel wrote: > > > > The SMCCC interface was created not as an alternative/complement to > > RNDR/RNDRRS, but to codify what several partners (including AWS) were > > doing at the time: > > Talking of which, any particular reasons not to have (happy to > contribute ours) a /dev/hwrng wrapper around SMCCC ? For various "gov > compliance" kind of thing it's useful in addition to seeding the kernel > CRNG. You mean like this? https://gitlab.arm.com/linux-arm/linux-ap/-/commit/87e3722f437f9c3f09397e0e9812e6509c94786a This is not reviewed nor widely tested, but I used it for assessing the quality of the SMCCC provided numbers on the Juno board using rngtest. I think one problem was that this opens the SMCCC to userland, so the entropy could be depleted from there (again under the assumption that this is really a problem in practice). I would be interested to hear opinions on this. Cheers, Andre _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel