From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from anor.bigon.be ([91.121.173.99]:44867 "EHLO anor.bigon.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753320AbdJUJCk (ORCPT ); Sat, 21 Oct 2017 05:02:40 -0400 Subject: Re: [tpmdd-devel] tpm device not showing up in /dev anymore To: Jerry Snitselaar , Jarkko Sakkinen Cc: Alexander.Steffen@infineon.com, tpmdd-devel@lists.sourceforge.net, linux-integrity@vger.kernel.org References: <47c4300b-8701-79a6-1c58-3a5853f4c5e3@debian.org> <595efb25-8d87-f39d-037f-9c9a98462339@debian.org> <857106e4bb864bb8a68b1381fffc8f50@MUCSE603.infineon.com> <20170831164015.3ajgwydgxtippwoz@rhwork> <0d9be244-ace0-030d-6ff9-c4e94c63b7e9@debian.org> <20170906040555.fqedhmo5277sd6fq@linux.intel.com> <20171014081318.busge2fhteusfjwx@rhwork> From: Laurent Bigonville Message-ID: Date: Sat, 21 Oct 2017 10:53:55 +0200 MIME-Version: 1.0 In-Reply-To: <20171014081318.busge2fhteusfjwx@rhwork> Content-Type: multipart/mixed; boundary="------------A9FE3B2D3EA7C477C0DA4586" Sender: linux-integrity-owner@vger.kernel.org List-ID: Le 14/10/17 a 10:13, Jerry Snitselaar a ecrit : > On Wed Sep 06 17, Jarkko Sakkinen wrote: >> On Fri, Sep 01, 2017 at 02:10:18PM +0200, Laurent Bigonville wrote: >>> Le 31/08/17 a 18:40, Jerry Snitselaar a ecrit : >>> > On Thu Aug 31 17, Alexander.Steffen@infineon.com wrote: >>> > > > Le 29/08/17 a 18:35, Laurent Bigonville a ecrit : >>> > > > > Le 29/08/17 a 18:00, Alexander.Steffen@infineon.com a ecrit : >>> > > > >>> An idea how to troubleshoot this? >>> > > > >> Can you run git bisect on the changes between 4.11 and >>> 4.12, so that >>> > > > >> we find the offending commit? It is probably sufficient to >>> limit the >>> > > > >> search to commits that touch something in drivers/char/tpm. >>> > > > > >>> > > > > I'll try and keep you posted. >>> > > > >>> > > > OK I've been able to bisect the problem and the bad commit is: >>> > > > >>> > > > e6aef069b6e97790cb127d5eeb86ae9ff0b7b0e3 is the first bad commit >>> > > > commit e6aef069b6e97790cb127d5eeb86ae9ff0b7b0e3 >>> > > > Author: Jerry Snitselaar >>> > > > Date: Mon Mar 27 08:46:04 2017 -0700 >>> > > > >>> > > > tpm_tis: convert to using locality callbacks >>> > > > >>> > > > This patch converts tpm_tis to use of the new tpm class ops >>> > > > request_locality, and relinquish_locality. >>> > > > >>> > > > With the move to using the callbacks, release_locality is >>> > > > changed so >>> > > > that we now release the locality even if there is no >>> > > > request pending. >>> > > > >>> > > > This required some changes to the tpm_tis_core_init code >>> path to >>> > > > make sure locality is requested when needed: >>> > > > >>> > > > - tpm2_probe code path will end up calling >>> > > > request/release through >>> > > > callbacks, so request_locality prior to tpm2_probe >>> not needed. >>> > > > >>> > > > - probe_itpm makes calls to tpm_tis_send_data which no >>> > > > longer calls >>> > > > request_locality, so add request_locality prior to >>> > > > tpm_tis_send_data >>> > > > calls. Also drop release_locality call in middleof >>> > > > probe_itpm, and >>> > > > keep locality until release_locality called at end of >>> > > > probe_itpm. >>> > > > >>> > > > Cc: Peter Huewe >>> > > > Cc: Jarkko Sakkinen >>> > > > Cc: Jason Gunthorpe >>> > > > Cc: Marcel Selhorst >>> > > > Signed-off-by: Jerry Snitselaar >>> > > > Reviewed-by: Jarkko Sakkinen >>> >>> > > > Tested-by: Jarkko Sakkinen >>> > > > Signed-off-by: Jarkko Sakkinen >>> >>> > > > >>> > > > :040000 040000 70234365da69959d47076ebb40c8d17f520c3e44 >>> > > > 72f21b446e45ea1003de75902b0553deb99157fd M drivers >>> > > > >>> > > >>> > > I've looked again at the code in question, but could not find >>> > > anything that is obviously wrong there. Locality is now >>> > > requested/released at slightly different points in the process than >>> > > before, but that's it. It does not seem to cause problems with the >>> > > majority of TPMs, since you are the first to report any, so >>> maybe it >>> > > is a quirk that only affects this device. >>> > > >>> > > Perhaps Jerry can help, since this is his change? >>> > > >>> > > Alexander >>> > >>> > Getting some caffeine in me, and starting to take a look. Adding >>> > Jarkko as well since this might involve the general locality changes. >>> > >>> > Laurent, if I send you a patch with some debugging code added, would >>> > you be able to run it on that system? I wasn't running into issues >>> > on the system I had with a 1.2 device, but I no longer have access >>> > to it. I'll see if I can find one in our labs and reproduce it there. >>> >>> Yes I should be able to do that >> >> Any findings? >> >> /Jarkko > > Okay, finally getting back to this. Looking at the code it isn't clear > to me > why the change is causing this. So while I stare at this some more > Laurent > could you reproduce it with this patch so I can see what the status and > access registers look like? Does anyone else on here happen to have a > Sinosun > tpm device? The systems I have access to with TPM1.2 devices don't > have this > issue. > > --8<-- > > diff --git a/drivers/char/tpm/tpm_tis_core.c > b/drivers/char/tpm/tpm_tis_core.c > index fdde971bc810..7d60a7e4b50a 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -258,6 +258,7 @@ static int tpm_tis_send_data(struct tpm_chip > *chip, const u8 *buf, size_t len) > int rc, status, burstcnt; > size_t count = 0; > bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND; > + u8 access; > > status = tpm_tis_status(chip); > if ((status & TPM_STS_COMMAND_READY) == 0) { > @@ -292,6 +293,11 @@ static int tpm_tis_send_data(struct tpm_chip > *chip, const u8 *buf, size_t len) > } > status = tpm_tis_status(chip); > if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) { > + rc = tpm_tis_read8(priv, TPM_ACCESS(priv->locality), > &access); > + if (rc < 0) > + dev_info(&chip->dev, "TPM_STS_DATA_EXPECT == 0: read > failure TPM_ACCESS(%d)\n", priv->locality); > + else > + dev_info(&chip->dev, "TPM_STS_DATA_EXPECT == 0: > locality: %d status: %x access: %x\n", priv->locality, status, access); > rc = -EIO; > goto out_err; > } > @@ -309,6 +315,11 @@ static int tpm_tis_send_data(struct tpm_chip > *chip, const u8 *buf, size_t len) > } > status = tpm_tis_status(chip); > if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) { > + rc = tpm_tis_read8(priv, TPM_ACCESS(priv->locality), &access); > + if (rc < 0) > + dev_info(&chip->dev, "TPM_STS_DATA_EXPECT != 0: read > failure TPM_ACCESS(%d)\n", priv->locality); > + else > + dev_info(&chip->dev, "TPM_STS_DATA_EXPECT != 0: locality: > %d status: %x access: %x\n", priv->locality, status, access); > rc = -EIO; > goto out_err; > } Please find here the dmesg output of the patched kernel [ Part 2, Application/GZIP (Name: "dmesg.txt.gz") 20 KB. ] [ Unable to print this part. ]