From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753371AbdBJQTr (ORCPT ); Fri, 10 Feb 2017 11:19:47 -0500 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:51696 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751460AbdBJQTo (ORCPT ); Fri, 10 Feb 2017 11:19:44 -0500 Message-ID: <1486743431.2502.6.camel@HansenPartnership.com> Subject: Re: [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code From: James Bottomley To: Jarkko Sakkinen , tpmdd-devel@lists.sourceforge.net Cc: linux-security-module@vger.kernel.org, Peter Huewe , Marcel Selhorst , Jason Gunthorpe , open list Date: Fri, 10 Feb 2017 08:17:11 -0800 In-Reply-To: <20170210123249.nrppoez2kdr2q4nw@intel.com> References: <20170208110713.14070-1-jarkko.sakkinen@linux.intel.com> <20170208110713.14070-7-jarkko.sakkinen@linux.intel.com> <20170210123249.nrppoez2kdr2q4nw@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote: > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote: > > From: James Bottomley [...] > > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle) > > +{ > > + struct tpm_space *space = &chip->work_space; > > + int i; > > + > > + for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) > > + if (space->session_tbl[i] == 0) > > + break; > > + if (i == ARRAY_SIZE(space->session_tbl)) { > > + dev_err(&chip->dev, "out of session slots\n"); > > This really should be dev_dbg. This was my reply to the comment the last time: I can do that, but I think this should be higher than debug. If this trips, something an application was doing will fail with a non TPM error and someone may wish to investigate why. Having a kernel message would help with that (but they won't see it if it's debug). I'm also leaning towards the idea that we should actually have one more _tbl slot than we know the TPM does, so that if someone goes over it's the TPM that gives them a real TPM out of memory error rather than the space code returning -ENOMEM. If you agree, I think it should be four for both sessions_tbl and context_tbl. So I really don't think it should be debug. Could we compromise on dev_info? James