Message-ID: <1492505735.2472.3.camel@sipsolutions.net> (sfid-20170418_105805_973108_07FD1D99)
Subject: Re: [PATCH V2 02/10] nl80211: allow multiple active scheduled scan
 requests
From: Johannes Berg <johannes@sipsolutions.net>
To: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>
Date: Tue, 18 Apr 2017 10:55:35 +0200
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On Tue, 2017-04-18 at 10:53 +0200, Johannes Berg wrote:
> Hi Arend,
> 
> Overall this looks good, and I've almost applied it - but I have a
> question on this patch.
> 
> You have this list:
> 
> > +	struct list_head sched_scan_req_list;
> >  	struct cfg80211_sched_scan_request __rcu *sched_scan_req;
> 
> but you kept this. In fact, it's even still *used*. I don't
> understand
> that part.
> 
> Also, you used RCU primitives for the new list, but you never
> actually
> used them - except in one place (in nl80211_stop_sched_scan) where
> it's
> actually not needed at all and the _rcu should be removed (since it
> holds the lock)
> 
> What's up with that?

Actually, I think I see what's up - you simply forgot to remove the
sched_scan_req member, and then didn't realize that it was still used
in nl80211_netlink_notify(), and that's the place that *does* need the
RCU stuff.

johannes