Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751347AbVJ0Rrk (ORCPT ); Thu, 27 Oct 2005 13:47:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751358AbVJ0Rrk (ORCPT ); Thu, 27 Oct 2005 13:47:40 -0400 Received: from zproxy.gmail.com ([64.233.162.196]:15050 "EHLO zproxy.gmail.com") by vger.kernel.org with ESMTP id S1751347AbVJ0Rrk convert rfc822-to-8bit (ORCPT ); Thu, 27 Oct 2005 13:47:40 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:mime-version:content-type:content-transfer-encoding:content-disposition; b=htHe1czxAuOSSih8rEgR2KO/huGVJVuQ9w7ibdMLwBy9dpHKi89zf01/2WvvQJYTEreyQihOhg53GicygLHNrMzOipAY/pUqdcKVP1BEj7o99Wwx1cOby3Lz1bKsIaOQVPeIubthFaKte0W3N73Hn3UUaRuGI70hhQReDPQGq7M= Message-ID: Date: Thu, 27 Oct 2005 10:47:38 -0700 From: Michael Madore To: linux-kernel@vger.kernel.org Subject: PCI-DMA: high address but no IOMMU MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2263 Lines: 70 Hi, I am seeing the following errors in /var/log/messages when booting 2.6.14-rc5 on a dual Opteron nforce4 motherboard with 8GB of RAM: Checking aperture... CPU 0: aperture @ be8c000000 size 32 MB Aperture from northbridge cpu 0 too small (32 MB) No AGP bridge found Your BIOS doesn't leave a aperture memory hole Please enable the IOMMU option in the BIOS setup This costs you 64 MB of RAM Mapping aperture over 65536 KB of RAM @ 8000000 ... PCI-DMA: Disabling AGP. PCI-DMA: More than 4GB of RAM and no IOMMU PCI-DMA: 32bit PCI IO may malfunction.<6>PCI-DMA: Disabling IOMMU. ... Attached scsi disk sda at scsi2, channel 0, id 0, lun 0 Kernel panic - not syncing: PCI-DMA: high address but no IOMMU. With 2.6.13, the systems boots OK with these messages in the log: Checking aperture... CPU 0: aperture @ 8000000 size 32 MB Aperture from northbridge cpu 0 too small (32 MB) No AGP bridge found Your BIOS doesn't leave a aperture memory hole Please enable the IOMMU option in the BIOS setup This costs you 64 MB of RAM Mapping aperture over 65536 KB of RAM @ 8000000 ... PCI-DMA: Disabling AGP. PCI-DMA: aperture base @ 8000000 size 65536 KB PCI-DMA: Reserving 64MB of IOMMU area in the AGP aperture Using git bisect, I narrowed the problem down to the following commit: 6142891a0c0209c91aa4a98f725de0d6e2ed4918 is first bad commit diff-tree 6142891a0c0209c91aa4a98f725de0d6e2ed4918 (from 357e11d4cbbbb959a88a9bdbbf33a10f160b0823) Author: Andi Kleen Date: Mon Sep 12 18:49:24 2005 +0200 [PATCH] x86-64: Avoid unnecessary double bouncing for swiotlb PCI_DMA_BUS_IS_PHYS has to be zero even when the GART IOMMU is disabled and the swiotlb is used. Otherwise the block layer does unnecessary double bouncing. Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds :040000 040000 d704d51d1e05f508f09c4388d3199cafbb9e3018 6a40204fd8b954634f2f7ea8f84861ed0a4bd88e M include Reverting this change allows 2.6.14-rc5 to boot. Mike - 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/