From mboxrd@z Thu Jan 1 00:00:00 1970 From: Or Gerlitz Subject: Re: [PATCH] mlx4: Use GFP_NOFS calls during the ipoib TX path when creating the QP Date: Wed, 26 Feb 2014 23:18:50 +0200 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Roland Dreier , Amir Vadai , Eli Cohen , Or Gerlitz , Eugenia Emantayev , "David S. Miller" , Mel Gorman , "netdev@vger.kernel.org" , linux-kernel To: Jiri Kosina Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Feb 26, 2014 at 12:55 AM, Jiri Kosina wrote: > On Wed, 26 Feb 2014, Or Gerlitz wrote: [...] > That definitely can be verified, and I am putting it on my TODO list. OK, thanks > But let's make sure that we don't diverge from the original problem too > much. Simple fact is that the deadlock is there when using connected mode, > and there is nothing preventing users from using it this way, therefore I > believe it should be fixed one way or another. the patch is titled with "mlx4:" -- do you expect the problem to come into play only when ipoib connected mode runs over the mlx4 driver? what's about mlx5 or other upstream IB drivers? I'll be looking on the details of the problem/solution, but this way or another the API being module param sounds more like a hack.... Do we have a way to tell a net-device instance they should do their memory allocations in a NOFS manner? if not, shouldn't we come up with more general injection method?