Re: [PACTH v1] cdc-wdm: Clear read pipeline in case of error

[Robert Foss]

On 2016-08-02 08:23 AM, Oliver Neukum wrote:
> On Thu, 2016-07-28 at 14:19 -0400, robert.foss@xxxxxxxxxxxxx wrote:
> > From: Prathmesh Prabhu <pprabhu@xxxxxxxxxxxx>
> >
> > Implemented queued response handling. This queue is processed every
> > time the
> > WDM_READ flag is cleared.
> >
> > In case of a read error, userspace may not actually read the data,
> > since the
> > driver returns an error through wdm_poll. After this, the underlying
> > device may
> > attempt to send us more data, but the queue is not processed. While
> > userspace is
> > also blocked, because the read error is never cleared.
>
> Could you explain why user space cannot just read more data?
> That will clear the error.

Userspace certainly could read more data, but for the case when 
userspace doesn't read and clear a potential an error, we still would 
like to not be stuck if the device sends more data.

I hope that answers your question, if not I'll try to be more elaborate.

> 	Regards
> 		Oliver