From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [patch net] mlxsw: spectrum: Add FDB lock to prevent session interleaving Date: Mon, 11 Jan 2016 00:21:03 -0500 (EST) Message-ID: <20160111.002103.979291218776108297.davem@davemloft.net> References: <1452414736-3571-1-git-send-email-jiri@resnulli.us> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, idosch@mellanox.com, eladr@mellanox.com, yotamg@mellanox.com, ogerlitz@mellanox.com To: jiri@resnulli.us Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:33175 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751035AbcAKFVH (ORCPT ); Mon, 11 Jan 2016 00:21:07 -0500 In-Reply-To: <1452414736-3571-1-git-send-email-jiri@resnulli.us> Sender: netdev-owner@vger.kernel.org List-ID: From: Jiri Pirko Date: Sun, 10 Jan 2016 09:32:16 +0100 > From: Ido Schimmel > > Dumping the FDB (invoked with a process context) or handling FDB > notifications (polled periodicly in delayed work) might each entail > multiple EMAD transcations due to the number of entries. > > While we only allow one EMAD transaction at a time, there is nothing > stopping the dump and notification processing sessions from > interleaving. However, this is forbidden by the hardware, so we need to > make sure only one of these sessions can run at a time. > > Solve this by adding a mutex ('fdb_lock'), as both kernel threads can > sleep while waiting for the response EMAD. > > Fixes: 56ade8fe3f ("mlxsw: spectrum: Add initial support for Spectrum ASIC") > Signed-off-by: Ido Schimmel > Signed-off-by: Jiri Pirko Jiri, I noticed you submitted both a net and a net-next variant of this same fix. Please don't ever do that. it's easiest if I just apply the 'net' variant and handle the merge issues when I pull 'net' into 'net-next', so that how I'm going to handle this change. Applied, thanks.