Subject: Re: [RFC 3/9] nl80211/cfg80211: add ability to enable TX on
 op-channel
From: Johannes Berg <johannes@sipsolutions.net>
To: "Goldenshtein, Victor" <victorg@ti.com>
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Date: Mon, 06 Feb 2012 22:01:30 +0100
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On Thu, 2012-02-02 at 18:06 +0200, Goldenshtein, Victor wrote:

> > So do we think that no safeguards here at all are acceptable? Not even
> > checking that radar detection was enabled, CAC time expired, etc.?
> 
> We can add a check whether dfs is supported by the driver
> (rdev->wiphy.features & NL80211_FEATURE_DFS).
> 
> The nl/cfg/mac doesn't have the info whether the radar detection is
> enabled and definitely doesn't heard about CAC time, on other hand the
> driver which starts/handles radar detection know whether it started or
> not. 

I'm just trying to make sure that you're OK with a simple two-line iw
patch being sufficient to start transmitting on radar channels ...

> I think the driver should perform this simple "sanity" checks,
> otherwise we"ll need to save different DFS states in the mac, not sure
> that this is what we want.

I disagree -- adding this in each driver, which will surely end up with
slightly different semantics, seems like a recipe for disaster.

johannes