On Tue, 2023-11-14 at 16:50 +0100, Johan Hovold wrote:
> Hi,
>
> I get the lockdep splat below when booting 6.7-rc1 with ath11k (Lenovo
> ThinkPad X13s).
>
> It's the new assert added by commit 0e8185ce1dde ("wifi: mac80211: check
> wiphy mutex in ops") which triggers in drv_get_txpower().
>
> Naively adding locking around the call in ieee80211_get_tx_power()
> (e.g. similar to 6b348f6e34ce ("wifi: mac80211: ethtool: always hold
> wiphy mutex")) does not work as there are other paths that call this
> function with the lock held, specifically via ieee80211_register_hw().
The latter we can just take the lock I guess?
> [ 7.127780] ieee80211_get_tx_power+0x19c/0x1c0 [mac80211]
> [ 7.127859] nl80211_send_iface+0x208/0x6a4 [cfg80211]
> [ 7.127946] nl80211_dump_interface+0x120/0x254 [cfg80211]
>
And here maybe we should just take the mutex at the nl80211 level.
That's the nice thing now, it's shared between the layers :)
I can't do it right now, but I'll take a look tomorrow.
johannes
