From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751208AbdAXObF (ORCPT ); Tue, 24 Jan 2017 09:31:05 -0500 Received: from mga06.intel.com ([134.134.136.31]:46714 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751009AbdAXObD (ORCPT ); Tue, 24 Jan 2017 09:31:03 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,278,1477983600"; d="scan'208";a="34773613" Date: Tue, 24 Jan 2017 16:30:42 +0200 From: Jarkko Sakkinen To: James Bottomley Cc: Jason Gunthorpe , open list , linux-security-module@vger.kernel.org, tpmdd-devel@lists.sourceforge.net Subject: Re: [tpmdd-devel] [PATCH RFC v4 4/5] tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c Message-ID: <20170124143042.rt3ldqfw7w3ty3yt@intel.com> References: <20170122234438.12102-1-jarkko.sakkinen@linux.intel.com> <20170122234438.12102-5-jarkko.sakkinen@linux.intel.com> <20170123164754.GA29360@obsidianresearch.com> <1485210503.2534.32.camel@HansenPartnership.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1485210503.2534.32.camel@HansenPartnership.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 23, 2017 at 02:28:23PM -0800, James Bottomley wrote: > On Mon, 2017-01-23 at 09:47 -0700, Jason Gunthorpe wrote: > > On Mon, Jan 23, 2017 at 01:44:32AM +0200, Jarkko Sakkinen wrote: > > > From: James Bottomley > > > > > > Signed-off-by: James Bottomley > > > > > > > I really think we should not use the ugly read/write interface for > > any new things. > > The R/W interface is needed for backward compat, so we don't really > have a choice (well, it could go in for long term deprecation, but I > found in SCSI that "long term" == "never"). I think no-one objects to > the ioctl interface ... it's just no-one feels strongly enough to build > and test it. I'm sure if you send patches, Jarkko will include them. > > James I feel that it is incorrect to speak backwards compatibility because we do no touch /dev/tpm0. We can only speak about backwards compatibility only after the API for tpms0 is in a kernel release. If someone uses that device, she must know the constraints that it has. /Jarkko