Re: regulatory: Operation already in progress

["Luis R. Rodriguez" <lrodriguez@atheros.com>]

On Sun, Jan 25, 2009 at 12:05:37PM -0800, Michael Buesch wrote:
> On Sunday 25 January 2009 20:36:56 Luis R. Rodriguez wrote:
> > On Sun, Jan 25, 2009 at 10:45:17AM -0800, Luis Rodriguez wrote:
> > > On Sun, Jan 25, 2009 at 10:41:38AM -0800, Michael Buesch wrote:
> > > > On Sunday 25 January 2009 19:21:07 Luis R. Rodriguez wrote:
> > > > > On Sun, Jan 25, 2009 at 05:22:42AM -0800, Michael Buesch wrote:
> > > > > > mb@quimby:~/kernel$ sudo iw reg set DE
> > > > > > command failed: Operation already in progress (-114)
> > > > > >
> > > > > > I wonder why this happens.
> > > > > > What I just did was install 2.6.28.2 and install today's compat-wireless.
> > > > > >
> > > > > > In dmesg I can see it succeeded once but it doesn't work anymore now.
> > > > > > [  973.992710] cfg80211: Calling CRDA for country: DE
> > > > > > [  973.998576] cfg80211: Regulatory domain changed to country: DE
> > > > > > [  973.998630]  (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
> > > > > > [  973.998691]  (2400000 KHz - 2483500 KHz @ 40000 KHz), (N/A, 2000 mBm)
> > > > > > [  973.998738]  (5150000 KHz - 5255000 KHz @ 40000 KHz), (N/A, 2301 mBm)
> > > > > > [  973.998785]  (5470000 KHz - 5650000 KHz @ 40000 KHz), (N/A, 3000 mBm)
> > > > >
> > > > > Had you called twice?
> > > >
> > > > yeah, once manually with iw and once with hostapd.
> > > >
> > > > > If so we now tell userspace when its there by -EALREADY,
> > > > > we were just silently accepting two consecutive calls before.
> > > >
> > > > Well, but it makes hostapd fail.
> > > > I think it's a bit weird to throw and error code. In general most programs
> > > > silently return success early, if an operation was already done.
> > >
> > > We can prevent to propagate -EALREADY to userspace -- sure, I'll cook
> > > up the patch.
> >
> > Actually we could also patch hostapd to deal with -EALREADY as a success too.
> > Its either that or we have nl80211 return 0 instead of -EALREADY. Jouni, any
> > preference?
> 
> I think returning an error doesn't make sense.
> All the set-regulatory nl80211 command does is "set the domain to X". So why does it
> fail, if it was already X before the call. All the caller wants is to select domain X.
> That's what he gets in any case. Whether it was set to X or not before the call shouldn't matter.
> It's also confusing to get a "command failed" from iw.

Yeah that is true, well I'll send a patch.

  Luis