From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752381Ab2G0O4m (ORCPT ); Fri, 27 Jul 2012 10:56:42 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:44754 "EHLO e4.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751462Ab2G0O4l (ORCPT ); Fri, 27 Jul 2012 10:56:41 -0400 Date: Fri, 27 Jul 2012 09:51:29 -0500 From: Kent Yoder To: "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org, tpmdd-devel@lists.sourceforge.net, m.selhorst@sirrix.com, safford@us.ibm.com Subject: Re: [PATCH 1/2] tpm: Move tpm_get_random api into the TPM device driver Message-ID: <20120727145129.GB22046@linux.vnet.ibm.com> References: <1339094567.21398.2.camel@key-ThinkPad-W510> <1339094834.21398.4.camel@key-ThinkPad-W510> <5011DC84.6010003@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5011DC84.6010003@zytor.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12072714-3534-0000-0000-00000AD592CE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 26, 2012 at 05:10:44PM -0700, H. Peter Anvin wrote: > On 06/07/2012 11:47 AM, Kent Yoder wrote: > >Move the tpm_get_random api from the trusted keys code into the TPM > >device driver itself so that other callers can make use of it. Also, > >change the api slightly so that the number of bytes read is returned in > >the call, since the TPM command can potentially return fewer bytes than > >requested. > > > >Signed-off-by: Kent Yoder > > I see a second problem with this patch: you don't seem to handle the > case where you get a short return anywhere in your code. Presumably > this should either be considered an error condition, or you need to > create a private wrapper which can loop and make additional > requests. > > As it is if you get a short return you simply proceed as if you had > gotten what you requested, since this was not an error mode > supported by the old code. Right, I did notice this but didn't think I was creating a regression so I left it. I'll add both a loop and then error out if that fails. Thanks, Kent > > -hpa > > -- > H. Peter Anvin, Intel Open Source Technology Center > I work for Intel. I don't speak on their behalf. >