Re: [PATCH V5 5/5] rpmsg: glink: unregister rpmsg device during endpoint destroy

[Arun Kumar Neelakantam]

On 5/14/2020 3:43 AM, Mathieu Poirier wrote:
> On Wed, May 13, 2020 at 10:40:06AM +0530, Arun Kumar Neelakantam wrote:
> > Rpmsg device unregister is not happening if channel close is triggered
> > from local side and causing re-registration of device failures.
> >
> > Unregister rpmsg device for local close in endpoint destroy path.
> >
> > Signed-off-by: Arun Kumar Neelakantam <aneela@xxxxxxxxxxxxxx>
> > ---
> >   drivers/rpmsg/qcom_glink_native.c | 9 +++++++++
> >   1 file changed, 9 insertions(+)
> >
> > diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
> > index 0e8a28c0..fc8ef66 100644
> > --- a/drivers/rpmsg/qcom_glink_native.c
> > +++ b/drivers/rpmsg/qcom_glink_native.c
> > @@ -1207,6 +1207,7 @@ static void qcom_glink_destroy_ept(struct rpmsg_endpoint *ept)
> >   {
> >   	struct glink_channel *channel = to_glink_channel(ept);
> >   	struct qcom_glink *glink = channel->glink;
> > +	struct rpmsg_channel_info chinfo;
> >   	unsigned long flags;
> >   
> >   	spin_lock_irqsave(&channel->recv_lock, flags);
> > @@ -1214,6 +1215,13 @@ static void qcom_glink_destroy_ept(struct rpmsg_endpoint *ept)
> >   	spin_unlock_irqrestore(&channel->recv_lock, flags);
> >   
> >   	/* Decouple the potential rpdev from the channel */
> > +	if (channel->rpdev) {
> If we proceed this way no other channel can have an rpdev.  I would hope that
> unregistration of rpdev would be more symetrical to what is done in patch 03.
>
> Thanks,
> Mathieu
Unregister here also required along with in qcom_glink_rx_close() 
otherwise if the remote open the channel again it map to stale rpmsg 
device.
> > +		strncpy(chinfo.name, channel->name, sizeof(chinfo.name));
> > +		chinfo.src = RPMSG_ADDR_ANY;
> > +		chinfo.dst = RPMSG_ADDR_ANY;
> > +
> > +		rpmsg_unregister_device(glink->dev, &chinfo);
> > +	}
> >   	channel->rpdev = NULL;
> >   
> >   	qcom_glink_send_close_req(glink, channel);
> > @@ -1477,6 +1485,7 @@ static void qcom_glink_rx_close(struct qcom_glink *glink, unsigned int rcid)
> >   
> >   		rpmsg_unregister_device(glink->dev, &chinfo);
> >   	}
> > +	channel->rpdev = NULL;
> >   
> >   	qcom_glink_send_close_ack(glink, channel->rcid);
> >   
> > --
> > 2.7.4