From: Robert Foss <robert.foss@collabora.com>
To: Oliver Neukum <oneukum@suse.com>
Cc: pprabhu@chromium.org, gregkh@linuxfoundation.org,
linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org
Subject: Re: [PACTH v1] cdc-wdm: Clear read pipeline in case of error
Date: Tue, 2 Aug 2016 09:54:04 -0400 [thread overview]
Message-ID: <04ca38d7-6538-d220-3fe7-7ece503ce4ad@collabora.com> (raw)
In-Reply-To: <1470140595.30985.20.camel@suse.com>
On 2016-08-02 08:23 AM, Oliver Neukum wrote:
> On Thu, 2016-07-28 at 14:19 -0400, robert.foss@collabora.com wrote:
>> From: Prathmesh Prabhu <pprabhu@chromium.org>
>>
>> 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
>
>
next prev parent reply other threads:[~2016-08-02 14:03 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-28 18:19 [PACTH v1] cdc-wdm: Clear read pipeline in case of error robert.foss
2016-08-02 12:23 ` Oliver Neukum
2016-08-02 13:54 ` Robert Foss [this message]
2016-08-02 13:59 ` Oliver Neukum
2016-08-02 14:37 ` Robert Foss
2016-08-03 10:39 ` Oliver Neukum
2016-08-04 17:44 ` Robert Foss
2016-08-07 8:59 ` Oliver Neukum
2016-08-08 14:38 ` Robert Foss
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