Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754509AbdDDRPp (ORCPT ); Tue, 4 Apr 2017 13:15:45 -0400 Received: from quartz.orcorp.ca ([184.70.90.242]:39889 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753477AbdDDRPo (ORCPT ); Tue, 4 Apr 2017 13:15:44 -0400 Date: Tue, 4 Apr 2017 11:15:33 -0600 From: Jason Gunthorpe To: Paul Menzel Cc: tpmdd-devel@lists.sourceforge.net, Linux Kernel Mailing List Subject: Re: [tpmdd-devel] Regression between Linux 3.16 and 4.8/4.9 on Lenovo X60 with coreboot Message-ID: <20170404171533.GA3255@obsidianresearch.com> References: <31e0ed69-174b-93ce-abf2-66cf08b1594e@molgen.mpg.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <31e0ed69-174b-93ce-abf2-66cf08b1594e@molgen.mpg.de> User-Agent: Mutt/1.5.24 (2015-08-30) X-Broken-Reverse-DNS: no host name found for IP address 10.0.0.156 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 796 Lines: 22 On Tue, Apr 04, 2017 at 06:29:06PM +0200, Paul Menzel wrote: > Unfortunately, there seems to have been a regression between Linux 3.16 > and 4.8 and 4.9, so that the Linux kernel doesn’t create the TPM > device. That old kernel did not check error codes when reading burst count, the new one does. It is quite possible the older kernel is failing to read burst count and subtly malfunctioning. It would be helpful if you could prove/disprove this statement by adding some debugging to 3.16. As to why the burst count cannot be read.. I don't know, check if increasing the retries helps, it could be this particular TPM is out of spec for the cold startup process. > Remove module and run `sudo modprobe tpm_tis itpm=1 force=1`. Is this really an 'itpm'? It doesn't look like it.. Jason