Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758625AbYGXPKw (ORCPT ); Thu, 24 Jul 2008 11:10:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752193AbYGXPKn (ORCPT ); Thu, 24 Jul 2008 11:10:43 -0400 Received: from mx1.redhat.com ([66.187.233.31]:43236 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752009AbYGXPKm (ORCPT ); Thu, 24 Jul 2008 11:10:42 -0400 Message-ID: <4888959D.6090907@redhat.com> Date: Thu, 24 Jul 2008 10:45:49 -0400 From: Prarit Bhargava User-Agent: Thunderbird 2.0.0.16 (X11/20080707) MIME-Version: 1.0 To: FUJITA Tomonori CC: joro@8bytes.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, jbarnes@virtuousgeek.org, ed.pollard@ibm.com, epollard@redhat.com Subject: Re: [PATCH]: PCI: GART iommu alignment fixes [v2] References: <488854DB.60307@redhat.com> <20080724193457S.fujita.tomonori@lab.ntt.co.jp> <20080724123755.GP31439@8bytes.org> <20080724223309C.fujita.tomonori@lab.ntt.co.jp> <4888925E.8050504@redhat.com> In-Reply-To: <4888925E.8050504@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1997 Lines: 46 >>> >> >> Yeah, I'm not against fixing IOMMUs to make alloc_consistent return >> the reqeuested size aligned memory. My point is that it's not likely >> to fix anything. Even with the patch, we hit the above problem because >> as I explained, the root cause of the problem is the boundary issue; >> we need to fix pci-dma.c >> >> > > Sorry, I misquoted code up there and was looking for a clear example > of where this would happen. The issue I'm trying to resolve didn't > happen on the skge -- it was just a convenient piece of code to > examine and point out ;) > Here's a case where USB has problems: BIOS-e820: 0000000000000000 - 000000000009f400 (usable) BIOS-e820: 000000000009f400 - 00000000000a0000 (reserved) BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 00000000f57f6800 (reserved) BIOS-e820: 00000000f57f6800 - 00000000f5800000 (ACPI data) BIOS-e820: 00000000f5800000 - 00000000fdc00000 (reserved) BIOS-e820: 00000000fdc00000 - 00000000fdc01000 (reserved) BIOS-e820: 00000000fdc10000 - 00000000fdc01000 (reserved) BIOS-e820: 00000000fdc20000 - 00000000fdc01000 (reserved) BIOS-e820: 00000000fdc30000 - 00000000fdc01000 (reserved) BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved) BIOS-e820: 00000000fec10000 - 00000000fec20000 (reserved) BIOS-e820: 00000000fec20000 - 00000000fec30000 (reserved) BIOS-e820: 00000000fee00000 - 00000000fee10000 (reserved) BIOS-e820: 00000000fee10000 - 00000000ff800000 (reserved) BIOS-e820: 00000000ff800000 - 0000000100000000 (reserved) BIOS-e820: 0000000100000000 - 00000017fffff000 (usable) I haven't tracked down what pci_alloc_consistent went wrong in usb-storage yet ... it seemed irrelevant because GART was broken. P. -- 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/