Re: Patch "wifi: mac80211: remove debugfs dir for virtual monitor" has been added to the 6.13-stable tree

Re: Patch "wifi: mac80211: remove debugfs dir for virtual monitor" has been added to the 6.13-stable tree

[Alexander Wetzel]

On 4/7/25 17:25, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
> 
>      wifi: mac80211: remove debugfs dir for virtual monitor
> 
> to the 6.13-stable tree which can be found at:
>      http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>       wifi-mac80211-remove-debugfs-dir-for-virtual-monitor.patch
> and it can be found in the queue-6.13 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
> 

The commit here is causing a sparse warning. Please always add commit 
861d0445e72e ("wifi: mac80211: Fix sparse warning for monitor_sdata") 
when you backport this patch to avoid that. (So far I got the  backport 
notification for 6.12 and 6.13.)

It's also no big deal when you decide to not backport this patch.

> 
> 
> commit 193bafe31a2a08b5631a98ecf148fa0d18e94b0d
> Author: Alexander Wetzel <Alexander@wetzel-home.de>
> Date:   Tue Feb 4 17:42:40 2025 +0100
> 
>      wifi: mac80211: remove debugfs dir for virtual monitor
>      
>      [ Upstream commit 646262c71aca87bb66945933abe4e620796d6c5a ]
>      
>      Don't call ieee80211_debugfs_recreate_netdev() for virtual monitor
>      interface when deleting it.
>      
>      The virtual monitor interface shouldn't have debugfs entries and trying
>      to update them will *create* them on deletion.
>      
>      And when the virtual monitor interface is created/destroyed multiple
>      times we'll get warnings about debugfs name conflicts.
>      
>      Signed-off-by: Alexander Wetzel <Alexander@wetzel-home.de>
>      Link: https://patch.msgid.link/20250204164240.370153-1-Alexander@wetzel-home.de
>      Signed-off-by: Johannes Berg <johannes.berg@intel.com>
>      Signed-off-by: Sasha Levin <sashal@kernel.org>
> 
> diff --git a/net/mac80211/driver-ops.c b/net/mac80211/driver-ops.c
> index 299d38e9e8630..2fc60e1e77a55 100644
> --- a/net/mac80211/driver-ops.c
> +++ b/net/mac80211/driver-ops.c
> @@ -116,8 +116,14 @@ void drv_remove_interface(struct ieee80211_local *local,
>   
>   	sdata->flags &= ~IEEE80211_SDATA_IN_DRIVER;
>   
> -	/* Remove driver debugfs entries */
> -	ieee80211_debugfs_recreate_netdev(sdata, sdata->vif.valid_links);
> +	/*
> +	 * Remove driver debugfs entries.
> +	 * The virtual monitor interface doesn't get a debugfs
> +	 * entry, so it's exempt here.
> +	 */
> +	if (sdata != local->monitor_sdata)
> +		ieee80211_debugfs_recreate_netdev(sdata,
> +						  sdata->vif.valid_links);
>   
>   	trace_drv_remove_interface(local, sdata);
>   	local->ops->remove_interface(&local->hw, &sdata->vif);
> diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
> index 806dffa48ef92..04b3626387309 100644
> --- a/net/mac80211/iface.c
> +++ b/net/mac80211/iface.c
> @@ -1212,16 +1212,17 @@ void ieee80211_del_virtual_monitor(struct ieee80211_local *local)
>   		return;
>   	}
>   
> -	RCU_INIT_POINTER(local->monitor_sdata, NULL);
> -	mutex_unlock(&local->iflist_mtx);
> -
> -	synchronize_net();
> -
> +	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
>   	ieee80211_link_release_channel(&sdata->deflink);
>   
>   	if (ieee80211_hw_check(&local->hw, WANT_MONITOR_VIF))
>   		drv_remove_interface(local, sdata);
>   
> +	RCU_INIT_POINTER(local->monitor_sdata, NULL);
> +	mutex_unlock(&local->iflist_mtx);
> +
> +	synchronize_net();
> +
>   	kfree(sdata);
>   }
>   

Re: Patch "wifi: mac80211: remove debugfs dir for virtual monitor" has been added to the 6.13-stable tree

[Greg KH]

On Mon, Apr 07, 2025 at 06:23:27PM +0200, Alexander Wetzel wrote:
> On 4/7/25 17:25, Sasha Levin wrote:
> > This is a note to let you know that I've just added the patch titled
> > 
> >      wifi: mac80211: remove debugfs dir for virtual monitor
> > 
> > to the 6.13-stable tree which can be found at:
> >      http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> > 
> > The filename of the patch is:
> >       wifi-mac80211-remove-debugfs-dir-for-virtual-monitor.patch
> > and it can be found in the queue-6.13 subdirectory.
> > 
> > If you, or anyone else, feels it should not be added to the stable tree,
> > please let <stable@vger.kernel.org> know about it.
> > 
> 
> The commit here is causing a sparse warning. Please always add commit
> 861d0445e72e ("wifi: mac80211: Fix sparse warning for monitor_sdata") when
> you backport this patch to avoid that. (So far I got the  backport
> notification for 6.12 and 6.13.)
> 
> It's also no big deal when you decide to not backport this patch.

Now queued up, thanks.

greg k-h