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Message-ID: <0848f5eba90a2125425da52b6b5f6f47ba9d6630.camel@sipsolutions.net>
Subject: Re: [PATCH 09/13] cfg80211: Save the regulatory domain when setting
 custom regulatory
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Nicolas Cavallari <Nicolas.Cavallari@green-communications.fr>,
        Kalle Valo <kvalo@codeaurora.org>,
        Toke =?ISO-8859-1?Q?H=F8iland-J=F8rgensen?= <toke@redhat.com>
Cc:     linux-wireless@vger.kernel.org
Date:   Thu, 03 Feb 2022 23:30:07 +0100
In-Reply-To: <cedc93ef-496f-a403-0089-b2a82477fe0f@green-communications.fr>
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         <e8e6afa6-275e-2cc5-6351-e1ed5eb0e0af@green-communications.fr>
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On Tue, 2021-10-12 at 12:24 +0200, Nicolas Cavallari wrote:
> > > 
> > > This patch somehow appears to break ath9k's eeprom hints and restrict
> > > it to the world regulatory domain on v5.12.10.
> > > 
> > > ath9k calls wiphy_apply_custom_regulatory() with its own kind of world
> > > regulatory domain, before it decodes hints from the eeprom and uses
> > > regulatory_hint() to request a specific alpha2.
> > > 
> > > With this patch, applying the hint fails because wiphy->regd is already set.
> > > If i revert this patch, ath9k works again.
> > 

Hm. It stands to reason that perhaps ath9k should call
wiphy_apply_custom_regulatory(NULL) (if that's possible) to reset the
knowledge of having a custom regulatory domain, before requesting the
correct one be applied by cfg80211 (and possibly even crda userspace).

I can't really say that I think the patch itself is wrong, even if it
caused this problem.

johannes