From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759720AbcDEWmA (ORCPT ); Tue, 5 Apr 2016 18:42:00 -0400 Received: from 8bytes.org ([81.169.241.247]:54329 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751884AbcDEWl6 (ORCPT ); Tue, 5 Apr 2016 18:41:58 -0400 Date: Wed, 6 Apr 2016 00:41:52 +0200 From: Joerg Roedel To: Steven Rostedt Cc: Paul Gortmaker , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Subject: Re: [PATCH] drivers/iommu: don't select DEBUG_FS for AMD_IOMMU_STATS Message-ID: <20160405224152.GK17838@8bytes.org> References: <1459041524-30929-1-git-send-email-paul.gortmaker@windriver.com> <20160405151951.GG11519@8bytes.org> <20160405123754.30786ede@grimm.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160405123754.30786ede@grimm.local.home> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 05, 2016 at 12:37:54PM -0400, Steven Rostedt wrote: > I will argue that people have asked me to move tracing out of debugfs > (which is why I created tracefs) because the problem with debugfs is > that it opens up a entire system that is not well scrutinized, and > holds lots of possible ways to crack the kernel. > > Disabling debugfs does help with the "security" point you mentioned > above. Yes, that reasoning makes more sense than "debug features are bad for production". It should've been part of the commit message. The AMD_IOMMU_STATS feature is on my list of things to remove anyway, it is mostly disabled and should be done differently (via per-device sysfs stats). So I am just going to remove it for now. Joerg