Return-path: Received: from s3.sipsolutions.net ([5.9.151.49]:35531 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbbJFNm4 (ORCPT ); Tue, 6 Oct 2015 09:42:56 -0400 Message-ID: <1444138971.1976.0.camel@sipsolutions.net> (sfid-20151006_154300_917862_12BA573B) Subject: Re: Deadlock in mac80211 running 3.18.11 + compat-wireless 2015-03-09 From: Johannes Berg To: projekt-wlan@fem.tu-ilmenau.de, linux-wireless@vger.kernel.org Date: Tue, 06 Oct 2015 15:42:51 +0200 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: commit 2c158887f1185e04b3763ae346da9f71fcbc4429 Author: Johannes Berg Date: Thu Mar 12 19:28:31 2015 +0100 mac80211: agg-tx: avoid sending DelBA with sta->lock held The rate control locking caused a potential deadlock here due to the locks being acquired in different orders, so that change cannot yet be applied. However, there's no fundamental reason for this code to hold the sta->lock while transmitting frames. Clearly it's better not to hold the lock for longer periods of time, which can happen here since we call all the way down to the driver. Change the code a bit to not hold it while doing that. Signed-off-by: Johannes Berg