From mboxrd@z Thu Jan 1 00:00:00 1970 From: Amit Shah Subject: Re: [PATCH v2 09/11] virtio: net: Add freeze, restore handlers to support S4 Date: Tue, 15 Nov 2011 17:59:36 +0530 Message-ID: <20111115122902.GA26378@amit-x200.redhat.com> References: <5b7834c9a30254220f9c079ba54d29abaf63db8f.1317311033.git.amit.shah@redhat.com> <20111002093324.GD29706@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20111002093324.GD29706@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, Virtualization List List-Id: virtualization@lists.linuxfoundation.org On (Sun) 02 Oct 2011 [11:33:26], Michael S. Tsirkin wrote: > On Thu, Sep 29, 2011 at 09:19:40PM +0530, Amit Shah wrote: > > Remove all the vqs on hibernation and re-create them after restoring > > from a hibernated image. This keeps networking working across > > hibernation. > > > > Signed-off-by: Amit Shah > > --- > > drivers/net/virtio_net.c | 28 ++++++++++++++++++++++++++++ > > 1 files changed, 28 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index dcd4b01..8b9ed43 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -1131,6 +1131,30 @@ static void __devexit virtnet_remove(struct virtio_device *vdev) > > free_netdev(vi->dev); > > } > > > > +#ifdef CONFIG_PM > > +static int virtnet_freeze(struct virtio_device *vdev) > > +{ > > + struct virtnet_info *vi = vdev->priv; > > I'm guessing we need to do something like netif_device_detach here, > otherwise guest might be in the process of using the vq for transmit at > this point. Done. > I think we also must make sure NAPI RX handler is not in progress. How to do that? napi_disable() / napi_enable() doesn't seem right (and it doesn't work, too). pci_disable_device() in the suspend routine may work? > We also might need to mask interrupts from the device > to prevent TX or RX from getting rescheduled? pci_disable_device() will help this too, right? Amit