Re: [cfg80211 / iwlwifi] setting wireless regulatory domain doesn't work.

[Sander Eikelenboom]

Wednesday, December 18, 2013, 8:43:28 PM, you wrote:

> On Wed, Dec 18, 2013 at 11:48:45AM +0100, Sander Eikelenboom wrote:
>> 
>> Wednesday, December 18, 2013, 10:26:25 AM, you wrote:
>> 
>> > Hi all,
>> 
>> > We really should be asking Luis to look at this who hasn't yet chimed
>> > in, presumably because he's between jobs (and travelling IIRC)
>> 
>> > On Wed, 2013-12-18 at 10:16 +0100, Arend van Spriel wrote:
>> >> On 12/17/2013 11:06 PM, Linus Torvalds wrote:
>> >> > We have literally had this *exact* same issue with firmware loading.
>> >> > Network drivers shouldn't try to load firmware at module load time.
>> >> > Same deal.
>> >> 
>> >> It is kind of a chicken and egg problem for (wireless) networking
>> >> drivers. To get IFF_UP from the network layer you have to register a
>> >> netdevice. For wireless drivers this means you have to register a wiphy
>> >> device with cfg80211 which flags capabilities and optionally are custom
>> >> regulatory domain. That information depends on the device and firmware
>> >> used. And there we have a full circle.
>> 
>> > This is all really beside the point.
>> 
>> > For this CRDA information, the kernel never actually *waits* for it, so
>> > in the case that there's no reply, it uses the built-in world domain. So
>> > it's not like request_firmware(), which will block boot forever, but
>> > it's also not like request_firmware_nowait() which will eventually time
>> > out and come back with an error if userspace isn't handling it (though
>> > now that firmware loading is built in ...)
>> 
>> > The issue is that it uses the built-in data *forever*, and what Sander
>> > said was "or it will block forever" but just meant that it never was
>> > able to do any further updates.
>> 
>> > It *doesn't* actually block the boot process or such. Everything Linus
>> > said is true but seems to have been written in understanding "blocks" as
>> > "blocking the boot process", rather than "blocking further updates".
>> 
>> > Regardless of this, even blocking further updates is a really bad idea.
>> > There are a few ways to handle this, but I'll let Luis poke at that.
>> 
>> Your description is correct, sorry if I was not clear.

> We have a timeout handler for this, I'll check to see what's going on
> by trying to reproduce on my end. Are you using wireless-testing ?

Originally 3.13-rc4, after that i tried with 3.13-rc4 with wireless-next pulled on top of it
(since there were major changes to reg.c) but the problem occurs with both.


>   Luis


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