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Date:   Mon, 21 Mar 2022 13:17:52 -0700
From:   Brian Norris <briannorris@chromium.org>
To:     Niels Dossche <dossche.niels@gmail.com>
Cc:     linux-wireless@vger.kernel.org,
        Amitkumar Karwar <amitkarwar@gmail.com>,
        Ganapathi Bhat <ganapathi017@gmail.com>,
        Sharvari Harisangam <sharvari.harisangam@nxp.com>,
        Xinming Hu <huxinming820@gmail.com>,
        Kalle Valo <kvalo@kernel.org>
Subject: Re: [PATCH RFT] mwifiex: add mutex lock for call in
 mwifiex_dfs_chan_sw_work_queue
Message-ID: <YjjdcG5NmzLOmjEu@google.com>
References: <20220319224751.72241-1-dossche.niels@gmail.com>
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On Sat, Mar 19, 2022 at 11:47:52PM +0100, Niels Dossche wrote:
> --- a/drivers/net/wireless/marvell/mwifiex/11h.c
> +++ b/drivers/net/wireless/marvell/mwifiex/11h.c
> @@ -285,6 +285,7 @@ void mwifiex_dfs_chan_sw_work_queue(struct work_struct *work)
>  	struct mwifiex_private *priv =
>  			container_of(delayed_work, struct mwifiex_private,
>  				     dfs_chan_sw_work);
> +	struct net_device *netdev;
>  
>  	bss_cfg = &priv->bss_cfg;
>  	if (!bss_cfg->beacon_period) {
> @@ -301,7 +302,11 @@ void mwifiex_dfs_chan_sw_work_queue(struct work_struct *work)
>  		return;
>  	}
>  
> +	netdev = priv->netdev;
> +
>  	mwifiex_dbg(priv->adapter, MSG,
>  		    "indicating channel switch completion to kernel\n");
> -	cfg80211_ch_switch_notify(priv->netdev, &priv->dfs_chandef);
> +	mutex_lock(&netdev->ieee80211_ptr->mtx);

A more appropriate route to this object might be priv->wdev.mtx. But
otherwise, I think this makes sense, and matches what
ath6kl_cfg80211_ch_switch_notify() and qtnf_event_handle_freq_change()
do. With the suggested change:

Reviewed-by: Brian Norris <briannorris@chromium.org>

Thanks.

> +	cfg80211_ch_switch_notify(netdev, &priv->dfs_chandef);
> +	mutex_unlock(&netdev->ieee80211_ptr->mtx);
>  }
> -- 
> 2.35.1
>