Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755593Ab0DNXi5 (ORCPT ); Wed, 14 Apr 2010 19:38:57 -0400 Received: from sous-sol.org ([216.99.217.87]:42117 "EHLO sequoia.sous-sol.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751597Ab0DNXiz (ORCPT ); Wed, 14 Apr 2010 19:38:55 -0400 Date: Wed, 14 Apr 2010 16:37:13 -0700 From: Chris Wright To: Pedro Ribeiro Cc: Chris Wright , David Woodhouse , Alan Stern , Daniel Mack , USB list , Andi Kleen , Kernel development list , Andrew Morton , Greg KH , iommu@lists.linux-foundation.org Subject: Re: USB transfer_buffer allocations on 64bit systems Message-ID: <20100414233713.GC25962@sequoia.sous-sol.org> References: <1271270197.31006.2133.camel@macbook.infradead.org> <20100414222550.GB25962@sequoia.sous-sol.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1950 Lines: 44 * Pedro Ribeiro (pedrib@gmail.com) wrote: > On 14 April 2010 23:25, Chris Wright wrote: > > * Pedro Ribeiro (pedrib@gmail.com) wrote: > >> Turns out CONFIG_DMAR was disabled because of PREEMPT_RT. I disabled > >> the later and enabled _DMAR. It took a long time to boot, something > >> wrong with the usb ports. You can see it in the appended dmesg from > >> time 11s to 100s. > >> > >> Then after it booted, I could barely move my USB mouse and lots of > >> errors appeared on dmesg. I tried to connect the DVB card but it > >> wouldn't even initialize. > > > > [ ?316.360045] DMAR:[DMA Write] Request device [00:02.0] fault addr 23c00000 > > [ ?316.360046] DMAR:[fault reason 05] PTE Write access is not set > > > > That's your video device. ?Do you have CONFIG_DMAR_BROKEN_GFX_WA=y? > > Where do I find this option in make menuconfig? Doesn't seem to be available... It's hidden behind CONFIG_BROKEN. The iommu=pt test puts all devices in a 1:1 mapping (the broken graphics workaround does that just for all graphics devices). > >> Enabling it with iommu=pt seemed to make no difference. > > > > It should (it should at least eliminate the video device problem). > > You are right, it does eliminate that problem. However I can't get any > of the USB devices to work, and the mouse is terribly slow. One more > dmesg attached. Thanks. It works for me here. I just booted 2.6.33-rt4 on my T400 w/ iommu on, and an external USB mouse is working fine (I don't have the same number of devices plugged in as you do). You are not seeing DMA faults which suggest that the IOMMU mappings are correct w.r.t. the DMA transactions that the controller is initiating. thanks, -chris -- 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/