From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga18.intel.com ([134.134.136.126]:56520 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727140AbeISAff (ORCPT ); Tue, 18 Sep 2018 20:35:35 -0400 Date: Tue, 18 Sep 2018 21:59:52 +0300 From: Jarkko Sakkinen To: Boris Ostrovsky Cc: peterhuewe@gmx.de, jgg@ziepe.ca, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, jgross@suse.com, dunlapg@umich.edu, "Dr. Greg Wettstein" , "Dr . Greg Wettstein" , stable@vger.kernel.org Subject: Re: [PATCH v3] tpm: Restore functionality to xen vtpm driver. Message-ID: <20180918185952.GA26508@linux.intel.com> References: <20180917225333.10426-1-boris.ostrovsky@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180917225333.10426-1-boris.ostrovsky@oracle.com> Sender: linux-integrity-owner@vger.kernel.org List-ID: On Mon, Sep 17, 2018 at 06:53:33PM -0400, Boris Ostrovsky wrote: > From: "Dr. Greg Wettstein" > > Functionality of the xen-tpmfront driver was lost secondary to > the introduction of xenbus multi-page support in commit ccc9d90a9a8b > ("xenbus_client: Extend interface to support multi-page ring"). > > In this commit pointer to location of where the shared page address > is stored 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. > > Fixes: ccc9d90a9a8b ("xenbus_client: Extend interface to support multi-page ring") > Signed-off-by: Dr. Greg Wettstein > > [boris: Updated commit message, added Fixes tag] > Signed-off-by: Boris Ostrovsky > Cc: stable@vger.kernel.org # v4.1+ > --- > 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 911475d36800..b150f87f38f5 100644 > --- a/drivers/char/tpm/xen-tpmfront.c > +++ b/drivers/char/tpm/xen-tpmfront.c > @@ -264,7 +264,7 @@ 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; > > -- > 2.17.1 > Reviewed-by: Jarkko Sakkinen /Jarkko