From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: [Bug 1612] Can't start VM when vif set and udev version is greater than 151 Date: Wed, 07 Jul 2010 10:34:41 -0700 Message-ID: <4C34BAB1.2040804@goop.org> References: <201007051720.o65HKsI6030388@bugzilla.xensource.com> <20100706151023.GA25263@phenom.dumpdata.com> <4C3369970200007800009C71@vpn.id2.novell.com> <20100706164642.GA31742@phenom.dumpdata.com> <4C34492B0200007800009EC0@vpn.id2.novell.com> <20100707144857.GF4823@phenom.dumpdata.com> <4C349C9C.2090909@goop.org> <20100707171830.GA4275@phenom.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100707171830.GA4275@phenom.dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Konrad Rzeszutek Wilk Cc: james.harper@bendigoit.com.au, xen-devel@lists.xensource.com, Jan Beulich , bastian@waldi.eu.org List-Id: xen-devel@lists.xenproject.org On 07/07/2010 10:18 AM, Konrad Rzeszutek Wilk wrote: > Here is a redux that is compile and regression tested. And I've > addressed your concerns Jeremy. Putting this on the BZ to solicit some > testing from folks. > > diff --git a/drivers/xen/netback/xenbus.c b/drivers/xen/netback/xenbus.c > index ba7b1de..7a9ae2e 100644 > --- a/drivers/xen/netback/xenbus.c > +++ b/drivers/xen/netback/xenbus.c > @@ -19,6 +19,7 @@ > > #include > #include > +#include > #include > #include "common.h" > > @@ -28,6 +29,7 @@ > printk("netback/xenbus (%s:%d) " fmt ".\n", __FUNCTION__, __LINE__, ##args) > #endif > > +static DECLARE_RWSEM(teardown_sem); > > static int connect_rings(struct backend_info *); > static void connect(struct backend_info *); > @@ -41,14 +43,19 @@ static int netback_remove(struct xenbus_device *dev) > //netback_remove_accelerators(be, dev); > > unregister_hotplug_status_watch(be); > - if (be->netif) { > + if (be->netif) > kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE); > + > + down_write(&teardown_sem); > + if (be->netif) { > xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status"); > netif_disconnect(be->netif); > be->netif = NULL; > } > - kfree(be); > dev_set_drvdata(&dev->dev, NULL); > + up_write(&teardown_sem); > + kfree(be); > + > return 0; > } > > @@ -187,9 +194,15 @@ static int netback_uevent(struct xenbus_device *xdev, struct kobj_uevent_env *en > kfree(val); > } > > - if (add_uevent_var(env, "vif=%s", netif->dev->name)) > - return -ENOMEM; > - > + down_read(&teardown_sem); > + be = dev_get_drvdata(&xdev->dev); > + if (be && be->netif) { > + if (add_uevent_var(env, "vif=%s", netif->dev->name)) { > The extra {} helps, but I was thinking more along the lines of: if (be && be->netif && add_uevent_var(env, "vif=%s", netif->dev->name)) { ... (with line break after the second && if that's too long). > + up_read(&teardown_sem); > + return -ENOMEM; > + } > + } > + up_read(&teardown_sem); > return 0; > } > > @@ -199,6 +212,7 @@ static void backend_create_netif(struct backend_info *be) > int err; > long handle; > struct xenbus_device *dev = be->dev; > + struct xen_netif *netif; > > if (be->netif != NULL) > return; > @@ -209,13 +223,13 @@ static void backend_create_netif(struct backend_info *be) > return; > } > > - be->netif = netif_alloc(&dev->dev, dev->otherend_id, handle); > - if (IS_ERR(be->netif)) { > - err = PTR_ERR(be->netif); > - be->netif = NULL; > + netif = netif_alloc(&dev->dev, dev->otherend_id, handle); > + if (IS_ERR(netif)) { > + err = PTR_ERR(netif); > xenbus_dev_fatal(dev, err, "creating interface"); > return; > } > + be->netif = netif; > > kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE); > } >