From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752419AbdATPAK (ORCPT ); Fri, 20 Jan 2017 10:00:10 -0500 Received: from wind.enjellic.com ([76.10.64.91]:45007 "EHLO wind.enjellic.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751962AbdATPAJ (ORCPT ); Fri, 20 Jan 2017 10:00:09 -0500 Date: Fri, 20 Jan 2017 09:00:02 -0600 From: "Dr. Greg Wettstein" Message-Id: <201701201500.v0KF02N1027871@wind.enjellic.com> Reply-To: greg@enjellic.com X-Mailer: Mail User's Shell (7.2.6-ESD1.0 03/31/2012) To: linux-kernel@vger.kernel.org Subject: [PATCH] tpm: Restore functionality to xen vtpm driver. Cc: Boris Ostrovsky , dgdegra@tycho.nsa.gov, konrad.wilk@oracle.com, jarkko.sakkinen@linux.intel.com X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.2.3 (wind.enjellic.com [0.0.0.0]); Fri, 20 Jan 2017 09:00:03 -0600 (CST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Functionality of the xen-tpmfront driver was lost secondary to the introduction of xenbus multi-page support in the following commit: ccc9d90a9a8b5c4ad7e9708ec41f75ff9e98d61d xenbus_client: Extend interface to support multi-page ring In this commit a pointer to the shared page address was being passed to the xenbus_grant_ring() function rather then the address of the shared page itself. This resulted in a situation where the driver would attach to the vtpm-stubdom but any attempt to send a command to the stub domain would timeout. A diagnostic finding for this regression is the following error message being generated when the xen-tpmfront driver probes for a device: <3>vtpm vtpm-0: tpm_transmit: tpm_send: error -62 <3>vtpm vtpm-0: A TPM error (-62) occurred attempting to determine the timeouts This fix is relevant to all kernels from 4.1 forward which is the release in which multi-page xenbus support was introduced. Daniel De Graaf formulated the fix by code inspection after the regression point was located. Cc: # 4.1- Suggested-by: Daniel De Graaf Signed-off-by: Dr. Greg Wettstein --- drivers/char/tpm/xen-tpmfront.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/tpm/xen-tpmfront.c b/drivers/char/tpm/xen-tpmfront.c index 3111f2778079..d1478f7b3f97 100644 --- a/drivers/char/tpm/xen-tpmfront.c +++ b/drivers/char/tpm/xen-tpmfront.c @@ -201,7 +201,7 @@ static int setup_ring(struct xenbus_device *dev, struct tpm_private *priv) return -ENOMEM; } - rv = xenbus_grant_ring(dev, &priv->shr, 1, &gref); + rv = xenbus_grant_ring(dev, priv->shr, 1, &gref); if (rv < 0) return rv; -- 2.11.0 As always, Dr. G.W. Wettstein, Ph.D. Enjellic Systems Development, LLC. 4206 N. 19th Ave. Specializing in information infra-structure Fargo, ND 58102 development. PH: 701-281-1686 FAX: 701-281-3949 EMAIL: greg@enjellic.com ------------------------------------------------------------------------------ "I will not eat aged beef." -- Johannes Christian Grosen Resurrection. --