| Message ID | 1369047912-31901-1-git-send-email-wei.liu2@citrix.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Mon, May 20, 2013 at 12:05:12PM +0100, Wei Liu wrote: > We should correctly free related resources (grant ref, memory page, evtchn) > when setup_netfront fails. Looks ok to me. > > Signed-off-by: Wei Liu <wei.liu2@citrix.com> > --- > drivers/net/xen-netfront.c | 33 +++++++++++++++++++++------------ > 1 file changed, 21 insertions(+), 12 deletions(-) > > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > index 1db10141..5770e3b 100644 > --- a/drivers/net/xen-netfront.c > +++ b/drivers/net/xen-netfront.c > @@ -1532,40 +1532,49 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); > > err = xenbus_grant_ring(dev, virt_to_mfn(txs)); > - if (err < 0) { > - free_page((unsigned long)txs); > - goto fail; > - } > + if (err < 0) > + goto grant_tx_ring_fail; > > info->tx_ring_ref = err; > rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); > if (!rxs) { > err = -ENOMEM; > xenbus_dev_fatal(dev, err, "allocating rx ring page"); > - goto fail; > + goto alloc_rx_ring_fail; > } > SHARED_RING_INIT(rxs); > FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); > > err = xenbus_grant_ring(dev, virt_to_mfn(rxs)); > - if (err < 0) { > - free_page((unsigned long)rxs); > - goto fail; > - } > + if (err < 0) > + goto grant_rx_ring_fail; > info->rx_ring_ref = err; > > err = xenbus_alloc_evtchn(dev, &info->evtchn); > if (err) > - goto fail; > + goto alloc_evtchn_fail; > > err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, > 0, netdev->name, netdev); > if (err < 0) > - goto fail; > + goto bind_fail; > netdev->irq = err; > return 0; > > - fail: > + /* If we fail to setup netfront, it is safe to just revoke access to > + * granted pages because backend is not accessing it at this point. > + */ > +bind_fail: > + xenbus_free_evtchn(dev, info->evtchn); > +alloc_evtchn_fail: > + gnttab_end_foreign_access_ref(info->rx_ring_ref, 0); > +grant_rx_ring_fail: > + free_page((unsigned long)rxs); > +alloc_rx_ring_fail: > + gnttab_end_foreign_access_ref(info->tx_ring_ref, 0); > +grant_tx_ring_fail: > + free_page((unsigned long)txs); > +fail: > return err; > } > > -- > 1.7.10.4 > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Wei Liu <wei.liu2@citrix.com> Date: Mon, 20 May 2013 12:05:12 +0100 > We should correctly free related resources (grant ref, memory page, evtchn) > when setup_netfront fails. > > Signed-off-by: Wei Liu <wei.liu2@citrix.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 1db10141..5770e3b 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1532,40 +1532,49 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); err = xenbus_grant_ring(dev, virt_to_mfn(txs)); - if (err < 0) { - free_page((unsigned long)txs); - goto fail; - } + if (err < 0) + goto grant_tx_ring_fail; info->tx_ring_ref = err; rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); if (!rxs) { err = -ENOMEM; xenbus_dev_fatal(dev, err, "allocating rx ring page"); - goto fail; + goto alloc_rx_ring_fail; } SHARED_RING_INIT(rxs); FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); err = xenbus_grant_ring(dev, virt_to_mfn(rxs)); - if (err < 0) { - free_page((unsigned long)rxs); - goto fail; - } + if (err < 0) + goto grant_rx_ring_fail; info->rx_ring_ref = err; err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) - goto fail; + goto alloc_evtchn_fail; err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, 0, netdev->name, netdev); if (err < 0) - goto fail; + goto bind_fail; netdev->irq = err; return 0; - fail: + /* If we fail to setup netfront, it is safe to just revoke access to + * granted pages because backend is not accessing it at this point. + */ +bind_fail: + xenbus_free_evtchn(dev, info->evtchn); +alloc_evtchn_fail: + gnttab_end_foreign_access_ref(info->rx_ring_ref, 0); +grant_rx_ring_fail: + free_page((unsigned long)rxs); +alloc_rx_ring_fail: + gnttab_end_foreign_access_ref(info->tx_ring_ref, 0); +grant_tx_ring_fail: + free_page((unsigned long)txs); +fail: return err; }
We should correctly free related resources (grant ref, memory page, evtchn) when setup_netfront fails. Signed-off-by: Wei Liu <wei.liu2@citrix.com> --- drivers/net/xen-netfront.c | 33 +++++++++++++++++++++------------ 1 file changed, 21 insertions(+), 12 deletions(-)