Re: [PATCH 3/7] mac80211: Improve error handling for off-channel operation

[Seth Forshee <seth.forshee@canonical.com>]

On Thu, Jan 31, 2013 at 04:15:50PM +0100, Johannes Berg wrote:
> On Tue, 2013-01-29 at 17:47 -0600, Seth Forshee wrote:
> > Errors in sending nullfunc or probe request frames during off-channel
> > operation may have undesirable consequences, e.g. failure to set
> > powersave at the AP. Add error handling for failures to transmit these
> > frames. In the case of a nullfunc failure, fail to go off-channel and
> > return an error to userspace. In the case of a failed probe request,
> > abort the scan.
> 
> That latter part seems excessive? Maybe increase the time to use a
> passive scan? But if there are multiple scan requests ...
> 
> Is all of this really worth the effort? The driver queues should be
> empty after the flush, after all, and the driver doesn't return any TX
> status. So what can really happen?

Hmm, yeah, maybe it is a bit excessive. The idea of falling back to a
passive scan is interesting though. I'll rip out the scan abort stuff
for v2 and think about doing the passive scan fallback as a future
enhancement.

Seth