On 4/12/2018 10:42 AM, solsTiCe d'Hiver wrote:

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?


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

Well, non issue... sight

2018-04-12 9:48 GMT+02:00 Arend van Spriel <arend.vanspr...@broadcom.com>:
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 ?



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.


2018-04-10 21:57 GMT+02:00 solsTiCe d'Hiver <solstice.dhi...@gmail.com>:


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

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

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
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)
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)

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 ??

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