Message-ID: <f0835218828401ed49ceacbb62c62284f4d99d95.camel@sipsolutions.net>
Subject: Re: [PATCH -next] mac80211: fix suspicious RCU usage in
 ieee80211_set_tx_power()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Bixuan Cui <cuibixuan@linux.alibaba.com>,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        linux-wireless@vger.kernel.org
Cc:     davem@davemloft.ne, kuba@kernel.org
Date:   Fri, 26 Nov 2021 13:02:42 +0100
In-Reply-To: <1636956548-114723-1-git-send-email-cuibixuan@linux.alibaba.com>
References: <1636956548-114723-1-git-send-email-cuibixuan@linux.alibaba.com>
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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