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Message-ID: <1495487095.26008.7.camel@sipsolutions.net> (sfid-20170522_230602_645383_E62D40B0)
Subject: Re: 4.12-RC2 BUG: scheduling while atomic: irq/47-iwlwifi
From: Johannes Berg <johannes@sipsolutions.net>
To: Arend Van Spriel <arend.vanspriel@broadcom.com>,
        Sander Eikelenboom <linux@eikelenboom.it>
Cc: linux-wireless <linux-wireless@vger.kernel.org>,
        netdev@vger.kernel.org
Date: Mon, 22 May 2017 23:04:55 +0200
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Hi Arend,

Sorry, I forgot that the original message wasn't Cc'ed to the wireless
list, only netdev.

> +++ b/net/wireless/scan.c
> @@ -322,9 +322,7 @@ static void cfg80211_del_sched_scan_req(struct
> cfg80211_regi
>  {
>         struct cfg80211_sched_scan_request *pos;
> 
> -       ASSERT_RTNL();
> -
> -       list_for_each_entry(pos, &rdev->sched_scan_req_list, list) {
> +       list_for_each_entry_rcu(pos, &rdev->sched_scan_req_list,
> list) {

[snip]

This looks fine, but perhaps in the above we should have some kind of
locking assertion, e.g.

	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());

johannes