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=-0.6 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID autolearn=ham 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 6F163C468C6 for ; Thu, 19 Jul 2018 20:27:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2295C206B7 for ; Thu, 19 Jul 2018 20:27:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=hansenpartnership.com header.i=@hansenpartnership.com header.b="YqkH31gm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2295C206B7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=HansenPartnership.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbeGSVMP (ORCPT ); Thu, 19 Jul 2018 17:12:15 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:43830 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727499AbeGSVMP (ORCPT ); Thu, 19 Jul 2018 17:12:15 -0400 Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 305618EE1DD; Thu, 19 Jul 2018 13:27:31 -0700 (PDT) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id X4BxADjUbOlu; Thu, 19 Jul 2018 13:27:31 -0700 (PDT) Received: from [153.66.254.194] (unknown [50.35.68.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id AE9DC8EE150; Thu, 19 Jul 2018 13:27:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=hansenpartnership.com; s=20151216; t=1532032050; bh=sc0ZEWKf5NOBv4V125GnLV5jEbj1mYXGn2GszcsovII=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=YqkH31gmOdoFxr+yRMo2RFlE+Bqbx71n9/hO9+zVJwJvGco2zrqh3VhTY6QAR2VnX vTH+ouda2cpN6Dyp+krDzZ5A4KJUWlvrT4Ue5MqWT47u8eQbYwltGshB4ii8fIR7qO rmFCQajxvS5t4PyJMHPiY5FeZUezHow972z4QGbo= Message-ID: <1532032049.3061.1.camel@HansenPartnership.com> Subject: Re: [PATCH] tpm: add support for partial reads From: James Bottomley To: Tadeusz Struk , jarkko.sakkinen@linux.intel.com Cc: jgg@ziepe.ca, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 19 Jul 2018 13:27:29 -0700 In-Reply-To: <0b9f0bb5-6620-0499-6680-5ec595167f23@intel.com> References: <153201555276.20155.1352499992826895966.stgit@tstruk-mobl1.jf.intel.com> <1532020750.5396.4.camel@HansenPartnership.com> <421c4b75-9e9d-7045-adad-797fd112898a@intel.com> <1532026030.3198.2.camel@HansenPartnership.com> <1532029979.3198.4.camel@HansenPartnership.com> <0b9f0bb5-6620-0499-6680-5ec595167f23@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2018-07-19 at 13:12 -0700, Tadeusz Struk wrote: > On 07/19/2018 12:52 PM, James Bottomley wrote: > > The ABI break is the error case as I outlined above.  We can't > > assume everyone uses the current interface without getting an error > > and one error and your hosed is a nasty failure case to change the > > interface to.  > > Well, if there is a broken application out there that doesn't work > today it will not work after this change neither. It doesn't have to be broken ... it could be using EFAULT to probe the buffer size for instance. That's the point of not breaking the ABI: you don't second guess what applications are doing. James