Re: [PATCH -next] mac80211: fix suspicious RCU usage in ieee80211_set_tx_power()

From: Johannes Berg
Date: Fri Nov 26 2021 - 07:39:38 EST


On Mon, 2021-11-15 at 14:09 +0800, Bixuan Cui wrote:
>
> diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
> index 1ab8483..14fbe9e 100644
> --- a/net/mac80211/cfg.c
> +++ b/net/mac80211/cfg.c
> @@ -2702,14 +2702,19 @@ static int ieee80211_set_tx_power(struct wiphy *wiphy,
> enum nl80211_tx_power_setting txp_type = type;
> bool update_txp_type = false;
> bool has_monitor = false;
> + int ret = 0;
> +
> + rtnl_lock();
>

This will almost certainly result in lockups, or at least lockdep
complaints, that's just wrong.

johannes