From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D8CDC433EF for ; Fri, 24 Jun 2022 13:28:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231986AbiFXN2S (ORCPT ); Fri, 24 Jun 2022 09:28:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231852AbiFXN2R (ORCPT ); Fri, 24 Jun 2022 09:28:17 -0400 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 670E2B7 for ; Fri, 24 Jun 2022 06:28:14 -0700 (PDT) Received: by theia.8bytes.org (Postfix, from userid 1000) id 52E59672; Fri, 24 Jun 2022 15:28:12 +0200 (CEST) Date: Fri, 24 Jun 2022 15:28:08 +0200 From: Joerg Roedel To: Robin Murphy Cc: will@kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, hch@lst.de, john.garry@huawei.com Subject: Re: [PATCH v2] iommu/dma: Add config for PCI SAC address trick Message-ID: References: <3f06994f9f370f9d35b2630ab75171ecd2065621.1654782107.git.robin.murphy@arm.com> <653fba02-7eef-5f0d-66dd-7599af84db86@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <653fba02-7eef-5f0d-66dd-7599af84db86@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 23, 2022 at 12:41:00PM +0100, Robin Murphy wrote: > On 2022-06-23 12:33, Joerg Roedel wrote: > > On Wed, Jun 22, 2022 at 02:12:39PM +0100, Robin Murphy wrote: > > > Thanks for your bravery! > > > > It already starts, with that patch I am getting: > > > > xhci_hcd 0000:02:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x000f address=0xff00ffffffefe000 flags=0x0000] > > > > In my kernel log. The device is an AMD XHCI controller and seems to > > funciton normally after boot. The message disappears with > > iommu.forcedac=0. > > > > Need to look more into that... > > Given how amd_iommu_domain_alloc() sets the domain aperture, presumably the > DMA address allocated was 0xffffffffffefe000? Odd that it gets bits punched > out in the middle rather than simply truncated off the top as I would have > expected :/ So even more weird, as a workaround I changed the AMD IOMMU driver to allocate a 4-level page-table and limit the DMA aperture to 48 bits. I still get the same message.