On 4/12/2018 10:42 AM, solsTiCe d'Hiver wrote:
> Hi.
>
> This is beyond my comprehension that you could assert this is a non issue.
Well. I am just saying that it is by design. There is no way for the
regulatory code to determine where you and your hardware actually reside
so instead it takes a conservative approach.
btw. can you change the global reg back to FR using iw reg set?
Regards,
Arend
> If this is a hint, then someone should take this as a hint , and not
> enforce it blindly.
>
> I loose the capability to use a lot of channels on a card because of
> the mis-behaving of another. Or the crda framework, or whatever.
>
> What is even more stupid is that the TL-W722N is a 2.4GHz only band
> and that breaks operation on the 5GHz band of the other card.
>
> I am not even speaking about the fact that I use this in monitor mode,
> hence I will never emit anything. But anyway... crda has already
> broken everyhting even before I am entering monitor mode for the
> cards.
>
> Well, non issue... sight
>
> 2018-04-12 9:48 GMT+02:00 Arend van Spriel <[email protected]>:
>> On 4/12/2018 9:00 AM, solsTiCe d'Hiver wrote:
>>>
>>> Nobody cares about this ?
>>>
>>> Should I report this as a bug to the LKML ? or elsewhere ? to
>>> ath9k_htc dev ? to crda dev ?
>>>
>>> Please.
>>
>>
>> Hi,
>>
>> I do not think nobody cares, but what you describe is actually no issue as
>> far as I can determine. Wifi cards are typically programmed with some
>> country code and both provide that as a regulatory hint to the regulatory
>> framework, which adapts to a regulatory domain in which only channels and
>> power limits are set that are allowed for both devices. That is why some of
>> the rules in the global set #98 are matching the FR set and some rules match
>> the CN set. And because FR uses ETSI DFS and CN uses FCC DFS you are loosing
>> all channels that require DFS.
>>
>> Regards,
>> Arend
>>
>>
>>>
>>> 2018-04-10 21:57 GMT+02:00 solsTiCe d'Hiver <[email protected]>:
>>>>
>>>> hi.
>>>>
>>>> I am trying to capture on 2 channels at the same time with 2 cards.
>>>>
>>>> One card is TP-Link TL-W722N v1 using ath9k_htc and the second one is
>>>> an Alfa AWUS051NH v2 using rt2800usb.
>>>>
>>>> I have tried this, first, on raspberry pi 0 W using archlinux-arm and
>>>> reproduced the issue on a netbook using archlinux x64 too using latest
>>>> kernel and drivers. (seems to happen on ubuntu 17.10 on dell laptop
>>>> too)
>>>>
>>>> So when the Alfa card is used alone using the default reg dom FR, one
>>>> can change to 112 channel for example (using iw dev wlan1 set channel
>>>> 112)
>>>>
>>>> But once the tp-link is plugged in, reg dom seems to become CN and one
>>>> can't change the alfa card to 112 channel.
>>>>
>>>> iw reg get output change from
>>>> global
>>>> country FR: DFS-ETSI
>>>> (2402 - 2482 @ 40), (N/A, 20), (N/A)
>>>> (5170 - 5250 @ 80), (N/A, 20), (N/A), AUTO-BW
>>>> (5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS, AUTO-BW
>>>> (5490 - 5710 @ 160), (N/A, 27), (0 ms), DFS
>>>> (57000 - 66000 @ 2160), (N/A, 40), (N/A)
>>>> to
>>>> global
>>>> country 98: DFS-UNSET
>>>> (2402 - 2482 @ 40), (N/A, 20), (N/A)
>>>> (5170 - 5250 @ 80), (N/A, 20), (N/A), AUTO-BW
>>>> (5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS, AUTO-BW
>>>> (57240 - 59400 @ 2160), (N/A, 28), (N/A)
>>>> (59400 - 63720 @ 2160), (N/A, 40), (N/A)
>>>> (63720 - 65880 @ 2160), (N/A, 28), (N/A)
>>>>
>>>> phy#2
>>>> country CN: DFS-FCC
>>>> (2402 - 2482 @ 40), (N/A, 20), (N/A)
>>>> (5170 - 5250 @ 80), (N/A, 23), (N/A), AUTO-BW
>>>> (5250 - 5330 @ 80), (N/A, 23), (0 ms), DFS, AUTO-BW
>>>> (5735 - 5835 @ 80), (N/A, 30), (N/A)
>>>> (57240 - 59400 @ 2160), (N/A, 28), (N/A)
>>>> (59400 - 63720 @ 2160), (N/A, 44), (N/A)
>>>> (63720 - 65880 @ 2160), (N/A, 28), (N/A)
>>>>
>>>>
>>>> and all the channels above 100 are marked as disabled in iw list
>>>> output (after the plug not before) for the alfa card
>>>>
>>>> It is as if the TL-WN722N has CN reg dom hard-coded and that switches
>>>> it globally to CN too ???
>>>>
>>>> Is this a bug in ath9k_htc ? a bug with the TL-WN722N card ??
>>
>>
On Thu, Apr 12, 2018 at 3:51 AM, Arend van Spriel
<[email protected]> wrote:
> On 4/12/2018 10:42 AM, solsTiCe d'Hiver wrote:
>>
>> Hi.
>>
>> This is beyond my comprehension that you could assert this is a non issue.
>
>
> Well. I am just saying that it is by design. There is no way for the
> regulatory code to determine where you and your hardware actually reside so
> instead it takes a conservative approach.
>
To say it another way: mixing regulatory domains on your host system
should result in a _smaller_ set of channels - ie only those channels
at the intersection of the two.
And another wrinkle to consider - one of the 802.11 amendments (can't
remember which one) actually causes the radio to listen to the beacons
around it, determine what the local regulatory domain is based on the
beacons it hears, and then lock to that regulatory domain. It's
possible for that information to be propagated up to the card's host
and the regulatory domain then would affect both cards. That's how
it's supposed to work, though I don't factually know Linux does this
in all cases. Could it be you're somewhere where CN is the local
regulatory domain and the TL-WN722N has this feature?
In any case, as Arend points out, despite the hand-wringing that
regulatory domains cause users trying to do something particular,
between certain rules and regulations and certain manufacturers bad
interpretations and implementations around it, there's little that can
be done about it. Fact is, your radio must comply to whatever
regulatory domain you are in, otherwise it's breaking the rules. And
people breaking the regulatory rules is part of what's gotten
governments to pass even worse (for us OSS guys) laws that tighten
those rules down further.
You asked who to contact. Its not the LKML - it's your relevant
government body. And certain manufacturers who improperly interpret
said rules because it's easier for them.
- Steve
--
Steve deRosier
Cal-Sierra Consulting LLC
https://www.cal-sierra.com/