From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:40350) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RlkQ6-0000kY-55 for qemu-devel@nongnu.org; Fri, 13 Jan 2012 11:56:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RlkQ0-0001pb-Cc for qemu-devel@nongnu.org; Fri, 13 Jan 2012 11:56:02 -0500 Received: from e4.ny.us.ibm.com ([32.97.182.144]:44745) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RlkQ0-0001nb-8S for qemu-devel@nongnu.org; Fri, 13 Jan 2012 11:55:56 -0500 Received: from /spool/local by e4.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 13 Jan 2012 11:55:38 -0500 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q0DGsNEU425074 for ; Fri, 13 Jan 2012 11:54:28 -0500 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q0DGsMdN008118 for ; Fri, 13 Jan 2012 11:54:22 -0500 Message-ID: <4F1061BA.1020809@us.ibm.com> Date: Fri, 13 Jan 2012 10:54:18 -0600 From: Anthony Liguori MIME-Version: 1.0 References: <1326462355-8203-1-git-send-email-aliguori@us.ibm.com> In-Reply-To: <1326462355-8203-1-git-send-email-aliguori@us.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] qdev: fix device_del by refactoring reference counting List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: qemu-devel@nongnu.org, Markus Armbruster On 01/13/2012 07:45 AM, Anthony Liguori wrote: > Commit 8eb0283 broken device_del by having too overzealous reference counting > checks. Move the reference count checks to qdev_free(), make sure to remove > the parent link on free, and decrement the reference count on property removal. > > Reported-by: Markus Armbruster > Signed-off-by: Anthony Liguori Applied. Regards, Anthony Liguori > --- > hw/qdev.c | 45 +++++++++++++++++++++++++++++++++++++++------ > 1 files changed, 39 insertions(+), 6 deletions(-) > > diff --git a/hw/qdev.c b/hw/qdev.c > index d0cf66d..e59f345 100644 > --- a/hw/qdev.c > +++ b/hw/qdev.c > @@ -376,11 +376,6 @@ int qdev_unplug(DeviceState *dev) > } > assert(dev->info->unplug != NULL); > > - if (dev->ref != 0) { > - qerror_report(QERR_DEVICE_IN_USE, dev->id?:""); > - return -1; > - } > - > qdev_hot_removed = true; > > return dev->info->unplug(dev); > @@ -465,6 +460,29 @@ static void qdev_property_del_all(DeviceState *dev) > } > } > > +static void qdev_property_del_child(DeviceState *dev, DeviceState *child, Error **errp) > +{ > + DeviceProperty *prop; > + > + QTAILQ_FOREACH(prop,&dev->properties, node) { > + if (strstart(prop->type, "child<", NULL)&& prop->opaque == child) { > + break; > + } > + } > + > + g_assert(prop != NULL); > + > + QTAILQ_REMOVE(&dev->properties, prop, node); > + > + if (prop->release) { > + prop->release(dev, prop->name, prop->opaque); > + } > + > + g_free(prop->name); > + g_free(prop->type); > + g_free(prop); > +} > + > /* Unlink device from bus and free the structure. */ > void qdev_free(DeviceState *dev) > { > @@ -491,6 +509,12 @@ void qdev_free(DeviceState *dev) > prop->info->free(dev, prop); > } > } > + if (dev->parent) { > + qdev_property_del_child(dev->parent, dev, NULL); > + } > + if (dev->ref != 0) { > + qerror_report(QERR_DEVICE_IN_USE, dev->id?:""); > + } > g_free(dev); > } > > @@ -1239,6 +1263,14 @@ static void qdev_get_child_property(DeviceState *dev, Visitor *v, void *opaque, > g_free(path); > } > > +static void qdev_release_child_property(DeviceState *dev, const char *name, > + void *opaque) > +{ > + DeviceState *child = opaque; > + > + qdev_unref(child); > +} > + > void qdev_property_add_child(DeviceState *dev, const char *name, > DeviceState *child, Error **errp) > { > @@ -1247,7 +1279,8 @@ void qdev_property_add_child(DeviceState *dev, const char *name, > type = g_strdup_printf("child<%s>", child->info->name); > > qdev_property_add(dev, name, type, qdev_get_child_property, > - NULL, NULL, child, errp); > + NULL, qdev_release_child_property, > + child, errp); > > qdev_ref(child); > g_assert(child->parent == NULL);