Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754695AbZAaEpS (ORCPT ); Fri, 30 Jan 2009 23:45:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751957AbZAaEpE (ORCPT ); Fri, 30 Jan 2009 23:45:04 -0500 Received: from bombadil.infradead.org ([18.85.46.34]:48238 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751698AbZAaEpD (ORCPT ); Fri, 30 Jan 2009 23:45:03 -0500 Date: Fri, 30 Jan 2009 23:44:54 -0500 From: Kyle McMartin To: Bhavesh Davda Cc: "David.Woodhouse@intel.com" , "mingo@elte.hu" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] intel-iommu: intel_iommu_domain_alloc should check 'dmar_disabled' Message-ID: <20090131044454.GA5184@bombadil.infradead.org> Reply-To: kyle@infradead.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1064 Lines: 25 On Fri, Jan 16, 2009 at 03:54:12PM -0800, Bhavesh Davda wrote: > > intel_iommu_domain_alloc() will try and iommu_alloc_domain(iommu), > which calls alloc_domain_mem() to allocate out of 'iommu_domain_cache'. > Unfortunately iommu_domain_cache will not be created if booted with > "intel_iommu=off", i.e. dmar_disabled = 1. > Hi Bhavesh, What's the callchain that can result in intel_iommu_domain_alloc being called? It looks like most possible callsites are checking intel_iommu_found, which will be 0 since we check dmar_disabled before calling init_dmars to enumerate the iommus. (I'm looking at 2.6.28.y right now, is there an interim between when you stumbled upon this two weeks ago and git head where it's no longer an issue? I guess it probably got missed due to folks travelling for LCA.) regards, Kyle -- 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/