Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755790AbZDNNji (ORCPT ); Tue, 14 Apr 2009 09:39:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752260AbZDNNj0 (ORCPT ); Tue, 14 Apr 2009 09:39:26 -0400 Received: from Mycroft.westnet.com ([216.187.52.7]:42531 "EHLO Mycroft.westnet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752178AbZDNNjZ (ORCPT ); Tue, 14 Apr 2009 09:39:25 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <18916.37351.872568.757026@stoffel.org> Date: Tue, 14 Apr 2009 09:38:47 -0400 From: "John Stoffel" To: Pete Zaitcev Cc: "John Stoffel" , Jarek Poplawski , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: usb_mon oops Re: tcpdump crashes 2.6.29.1 (and 2.6.29-rc5) In-Reply-To: <20090413174105.b03a1f19.zaitcev@redhat.com> References: <18906.49779.243047.207639@stoffel.org> <20090407120022.GA6519@ff.dom.local> <18907.28788.965069.573489@stoffel.org> <20090407130403.e0061a8d.zaitcev@redhat.com> <18908.42166.404232.721757@stoffel.org> <20090408232344.afed8103.zaitcev@redhat.com> <18909.65347.234817.29689@stoffel.org> <20090413174105.b03a1f19.zaitcev@redhat.com> X-Mailer: VM 8.0.9 under Emacs 22.3.1 (i486-pc-linux-gnu) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1881 Lines: 46 >>>>> "Pete" == Pete Zaitcev writes: Pete> On Thu, 9 Apr 2009 09:59:31 -0400, "John Stoffel" wrote: >> Here's a dmesg of bootup: >> [ 0.000000] Linux version 2.6.29.1 (john@sail) (gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) ) #24 SMP PREEMPT Tue Apr 7 11:30:52 EDT 2009 >> [ 0.000999] Checking aperture... >> [ 0.000999] No AGP bridge found >> [ 0.000999] Node 0: aperture @ 20000000 size 32 MB >> [ 0.000999] Aperture pointing to e820 RAM. Ignoring. >> [ 0.000999] Your BIOS doesn't leave a aperture memory hole >> [ 0.000999] Please enable the IOMMU option in the BIOS setup >> [ 0.000999] This costs you 64 MB of RAM >> [ 0.000999] Mapping aperture over 65536 KB of RAM @ 20000000 >> [ 1396.271782] BUG: unable to handle kernel paging request at ffff880020a15cc0 Pete> So 20a15000 is in the aperture. Oh well, I screwed up. I meant Pete> to check for this back in 2006 but forgot, and miraclously it Pete> worked until now. Pete> Here's the problem: Pete> pg = phys_to_page(dma_addr); Pete> map = kmap_atomic(pg, KM_IRQ0); Pete> offset = mon_copy_to_buff(rp, offset, map + page_off, step_len); Pete> kunmap_atomic(map, KM_IRQ0); Pete> Obviously we don't want the page that's overlayed by the Pete> aperture, but the page where IOMMU is pointing. Thanks for finding this! I was working on getting 2.6.25 built and running, but it hates my Forcedeth ethernet ports and won't bring them up, which complicated testing immensely. It's tough when your home directory is on NFS and the network is down... I'm happy to test any patches you have. Thanks, John -- 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/