From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756363Ab3E1Uqv (ORCPT ); Tue, 28 May 2013 16:46:51 -0400 Received: from emvm-gh1-uea08.nsa.gov ([63.239.67.9]:49751 "EHLO nsa.gov" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756102Ab3E1Uqu (ORCPT ); Tue, 28 May 2013 16:46:50 -0400 X-TM-IMSS-Message-ID: <701b402d000f6b07@nsa.gov> Message-ID: <51A51782.2070406@tycho.nsa.gov> Date: Tue, 28 May 2013 16:45:54 -0400 From: Daniel De Graaf Organization: National Security Agency User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130402 Thunderbird/17.0.5 MIME-Version: 1.0 To: Konrad Rzeszutek Wilk CC: linux-kernel@vger.kernel.org, tpmdd-devel@lists.sourceforge.net, xen-devel@lists.xen.org, mail@srajiv.net, tpmdd@selhorst.net, tpmdd@sirrix.com, leosilva@linux.vnet.ibm.com, adlai@linux.vnet.ibm.com, shpedoikal@gmail.com Subject: Re: [PATCH v3] drivers/tpm: add xen tpmfront interface References: <1369755632-2753-1-git-send-email-dgdegra@tycho.nsa.gov> <20130528203216.GA25602@phenom.dumpdata.com> In-Reply-To: <20130528203216.GA25602@phenom.dumpdata.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/28/2013 04:32 PM, Konrad Rzeszutek Wilk wrote: > On Tue, May 28, 2013 at 11:40:32AM -0400, Daniel De Graaf wrote: >> This is a complete rewrite of the Xen TPM frontend driver, taking >> advantage of a simplified frontend/backend interface and adding support >> for cancellation and timeouts. The backend for this driver is provided >> by a vTPM stub domain using the interface in Xen 4.3. >> >> Signed-off-by: Daniel De Graaf >> Acked-by: Matthew Fioravante > > .. snip.. >> +static void ring_free(struct tpm_private *priv) >> +{ >> + if (!priv) >> + return; >> + >> + if (priv->ring_ref) >> + gnttab_end_foreign_access(priv->ring_ref, 0, >> + (unsigned long)priv->shr); >> + else >> + free_page((unsigned long)priv->shr); >> + >> + if (priv->chip && priv->chip->vendor.irq) >> + unbind_from_irqhandler(priv->chip->vendor.irq, priv); > > You are missing: > > if (priv->evtchn != INVALID_EVTCHN) > xenbus_free_evtchn(priv->xdev, priv->evtchn); This is already handled by unbind_from_irqhandler when it calls unbind_from_irq, which gets the event channel from the IRQ. This should be the same event channel as priv->evtchn, and it already calls EVTCHNOP_close on this port. Calling xenbus_free_evtchn on the event channel again will just double-free the port. This is done the same way as drivers/block/xen-blkfront.c, for reference. >> + >> + kfree(priv); >> +} >> + -- Daniel De Graaf National Security Agency