Re: [PATCH] mac80211: always pick a basic rate to tx RTS/CTS for pre-HT rates

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2013-04-09 at 12:55 +0200, Karl Beldan wrote:
> On Tue, Apr 09, 2013 at 12:29:16PM +0200, Johannes Berg wrote:
> > On Fri, 2013-04-05 at 12:06 +0200, Karl Beldan wrote:
> > > From: Karl Beldan <karl.beldan@rivierawaves.com>
> > > 
> > > When the 1st rate control entry is a pre-HT rate we want to set
> > > rts_cts_rate_idx "as the fastest basic rate that is not faster than the
> > > data rate"(code comments).
> > > But in case some bss allowed rate indexes are lower than the lowest bss
> > > basic rate, if the rate control selects a rate among the formers for its
> > > 1st rate control entry, rts_cts_rate_idx remains 0 and is not a basic
> > > rate index.
> > > This commit sets rts_cts_rate_idx to the lowest bss basic rate index in
> > > this situation.
> > 
> > I guess it's a good thing you're looking at this code. However, I'm not
> > sure what you're doing here is correct. In this case, the PHY mandatory
> > rates should be used. See 9.7.6.5.2 "Selection of a rate or MCS":
> > 
> Thanks for looking at this.
> 
> You are quoting the chapter for "control _response_ frames" which does
> not apply here (even CTS-to-self are not control response frames).

Oh, oops, confused. But then you look at 9.7.6.2 "Rate selection for
control frames that initiate a TXOP", which just mandates that you use
any rate that the receiver supports, so why bother doing basic rates
etc. at all?

johannes