Re: [PATCH 2/4] net: mac80211: scan.c: Fix RCU list related warnings.

[Johannes Berg]

On Thu, 2020-04-09 at 13:58 +0530, madhuparnabhowmik10@xxxxxxxxx wrote:
> From: Madhuparna Bhowmik <madhuparnabhowmik10@xxxxxxxxx>
> 
> This patch fixes the following warning:
> 
> WARNING: suspicious RCU usage
> [   84.530619] 5.6.0+ #4 Not tainted
> [   84.530637] -----------------------------
> [   84.530658] net/mac80211/scan.c:454 RCU-list traversed in non-reader section!!
> 
> As local->mtx is held in __ieee80211_scan_completed()

Yeah, but is that really the right lock? I think it should be RTNL or
iflist_mtx for the interface list.

(Not that this is necessarily a good idea - we perhaps should clean up
and significantly reduce the number of locks used here.)

johannes