Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752751AbYCSTaj (ORCPT ); Wed, 19 Mar 2008 15:30:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753712AbYCST0U (ORCPT ); Wed, 19 Mar 2008 15:26:20 -0400 Received: from mtagate6.de.ibm.com ([195.212.29.155]:56441 "EHLO mtagate6.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753681AbYCST0R (ORCPT ); Wed, 19 Mar 2008 15:26:17 -0400 In-Reply-To: Subject: Re: [PATCH 1/3] Infiniband: make ehca_pd use struct pid pointer rather than pid_t To: Roland Dreier Cc: Christoph Raisch , general@lists.openfabrics.org, Hal Rosenstock , Linux Kernel Mailing List , Roland Dreier , Sean Hefty , Pavel Emelyanov X-Mailer: Lotus Notes Release 7.0 HF277 June 21, 2006 Message-ID: From: Hoang-Nam Nguyen Date: Tue, 18 Mar 2008 16:52:27 +0100 X-MIMETrack: Serialize by Router on D12ML065/12/M/IBM(Release 7.0.2FP2HF322 | September 26, 2007) at 18/03/2008 16:52:28 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1453 Lines: 31 Hi Roland! > > The task_struct->tgid field is about to become deprecated, due to > > pid namespaces make tasks have many pids, not one. The infiniband > > driver is one of the code, that still uses it in some places. > > Looks fine in terms of the changes it makes, but actually it seems > that the ehca use of this is completely bogus and the ownership > checking should be removed. > > The core ib_uverbs module has checks that make sure that objects can > only be accessed through the file that they were created through; of > course there are tricky ways a file can be passed from one process to > another, but I don't think we want to disallow userspace processes > from trying to do interesting stuff as long as it doesn't hurt anything. > > In other words-- ehca shouldn't be looking at tgids or anything like > that at all. If there are missing checks then they should be in the > core userspace verbs stuff; but I think what we have is actually OK. > > ehca guys, what do you think? Reason for above checking is to prevent a child process releasing a resource that the parent process has created and still wants to use. Do you think that's something we can generalize into ib_core? Regards Nam -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/