Re: [PATCH] vhost: make destroy callback on VHOST_USER_RESET_OWNER

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Tue, Nov 10, 2015 at 12:51:42PM +0900, Tetsuya Mukawa wrote:
> On 2015/11/10 11:25, Yuanhan Liu wrote:
> > On Mon, Nov 09, 2015 at 06:15:13PM -0800, Rich Lane wrote:
> >> QEMU sends this message first when shutting down. There was previously no way
> >> for the dataplane to know that the virtio_net instance had become unusable and
> >> it would segfault when trying to do RX/TX.
> >>
> >> Signed-off-by: Rich Lane <rlane@bigswitch.com>
> > Thanks. Even I have same patch in my patch queue (I have some other
> > issues to fix), you got my ack.
> >
> > Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> >
> > 	--yliu
> >
> 
> Hi Liu and Rich,
> 
> How about saving "dev->ifname" while processing reset_owner like
> "dev->device_fh"?
> It was only set when connection is established.
> But so far, it will be cleared when reset_owner message comes.
> Probably it should be cleared when unix domain socket connection is closed.

Yes, you are right, and I was thinking (and doing) same stuff. And we
may need save few more fields.

(For Thomas, this patch is still needed).

	--yliu
> 
> >> ---
> >>  lib/librte_vhost/virtio-net.c | 3 +++
> >>  1 file changed, 3 insertions(+)
> >>
> >> diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
> >> index 14278de..39a6a5e 100644
> >> --- a/lib/librte_vhost/virtio-net.c
> >> +++ b/lib/librte_vhost/virtio-net.c
> >> @@ -436,6 +436,9 @@ reset_owner(struct vhost_device_ctx ctx)
> >>  	if (dev == NULL)
> >>  		return -1;
> >>  
> >> +	if (dev->flags & VIRTIO_DEV_RUNNING)
> >> +		notify_ops->destroy_device(dev);
> >> +
> >>  	device_fh = dev->device_fh;
> >>  	cleanup_device(dev);
> >>  	init_device(dev);
> >> -- 
> >> 1.9.1