On 11/10/2021 12:51, Kalle Valo wrote:

Nicolas Cavallari [off-list ref] writes:

quoted

On 29/11/2020 16:30, Luca Coelho wrote:

quoted

From: Ilan Peer <redacted>

When custom regulatory was set, only the channels setting was updated, but
the regulatory domain was not saved. Fix it by saving it.

Signed-off-by: Ilan Peer <redacted>
Signed-off-by: Luca Coelho <redacted>
---
   net/wireless/reg.c | 8 ++++++++
   1 file changed, 8 insertions(+)

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index a04fdfb35f07..094492b62f8a 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c

@@ -2547,6 +2547,7 @@ static void handle_band_custom(struct wiphy *wiphy,
   void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
   				   const struct ieee80211_regdomain *regd)
   {
+	const struct ieee80211_regdomain *new_regd, *tmp;
   	enum nl80211_band band;
   	unsigned int bands_set = 0;
   @@ -2566,6 +2567,13 @@ void wiphy_apply_custom_regulatory(struct

wiphy *wiphy,
   	 * on your device's supported bands.
   	 */
   	WARN_ON(!bands_set);
+	new_regd = reg_copy_regd(regd);
+	if (IS_ERR(new_regd))
+		return;
+
+	tmp = get_wiphy_regdom(wiphy);
+	rcu_assign_pointer(wiphy->regd, new_regd);
+	rcu_free_regdom(tmp);
   }
   EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
   

Hello,

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.

I have lost track, is this regression fixed now or is it sill
unresolved?

I admit i forgot about it after reverting the patch and haven't tried a new 
kernel with ath9k since then, but from a quick glance, the code hasn't changed. 
I'll try a new kernel tomorrow.