Re: [PATCH 2/3] mac80211: create a STA entry for a WDS interface after receiving a beacon

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2011-05-31 at 21:46 +0200, Felix Fietkau wrote:
> On 2011-05-31 9:31 PM, Johannes Berg wrote:
> > On Tue, 2011-05-31 at 21:16 +0200, Felix Fietkau wrote:
> >
> >>  +	rcu_read_lock();
> >>  +
> >>  +	sta = sta_info_get(sdata, sdata->u.wds.remote_addr);
> >>  +
> >>  +	if (!sta) {
> >>  +		rcu_read_unlock();
> >>  +		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
> >>  +				     GFP_KERNEL);
> >>  +		if (!sta)
> >>  +			return;
> >>  +
> >>  +		new = true;
> >>  +	}
> >
> > ...
> >
> >>  +	rcu_read_unlock();
> >
> > definitely doesn't look right.
> It's a bit weird because in the case of a new sta being allocated, the 
> rcu read lock is acquired by sta_info_insert_rcu, and the code inbetween 
> does not need to be covered by the rcu read lock as the sta entry has 
> not been added to the list yet.
> It should be correct though, unless I'm missing something...

Oh right, I forgot about that.

johannes