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charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" T24gV2VkLCBPY3QgMTQsIDIwMjAgYXQgMDg6Mzc6MDZQTSArMDEwMCwgQW5kcmV3IENvb3BlciB3 cm90ZToKPiBPbiAxNC8xMC8yMDIwIDIwOjI4LCBKYXNvbiBBbmRyeXVrIHdyb3RlOgo+ID4gSGks Cj4gPgo+ID4gQnVnIG9wZW5lZCBhdCBodHRwczovL2dpdGxhYi5mcmVlZGVza3RvcC5vcmcvZHJt L2ludGVsLy0vaXNzdWVzLzI1NzYKPiA+Cj4gPiBJJ20gc2VlaW5nIERNQSBmYXVsdHMgZm9yIHRo ZSBpOTE1IGdyYXBoaWNzIGhhcmR3YXJlIG9uIGEgRGVsbAo+ID4gTGF0aXR1ZGUgNTUwMC4gVGhl c2Ugd2VyZSBjYXB0dXJlZCB3aGVuIEkgcGx1Z2dlZCBpbnRvIGEgRGVsbAo+ID4gVGh1bmRlcmJv bHQgZG9jayB3aXRoIHR3byBEaXNwbGF5UG9ydCBtb25pdG9ycyBhdHRhY2hlZC4gIFhlbiA0LjEy LjQKPiA+IHN0YWdpbmcgYW5kIExpbnV4IDUuNC43MCAoYW5kIHNvbWUgZWFybGllciB2ZXJzaW9u cykuCj4gPgo+ID4gT2N0IDE0IDE4OjQxOjQ5LjA1NjQ5MCBrZXJuZWw6WyAgIDg1LjU3MDM0N10g W2RybTpnZW44X2RlX2lycV9oYW5kbGVyCj4gPiBbaTkxNV1dICpFUlJPUiogRmF1bHQgZXJyb3Jz IG9uIHBpcGUgQTogMHgwMDAwMDA4MAo+ID4gT2N0IDE0IDE4OjQxOjQ5LjA1NjQ5NCBrZXJuZWw6 WyAgIDg1LjU3MDM5NV0gW2RybTpnZW44X2RlX2lycV9oYW5kbGVyCj4gPiBbaTkxNV1dICpFUlJP UiogRmF1bHQgZXJyb3JzIG9uIHBpcGUgQTogMHgwMDAwMDA4MAo+ID4gT2N0IDE0IDE4OjQxOjQ5 LjA1NjU4OSBWTSBoeXBlcnZpc29yOiAoWEVOKSBbVlQtRF1ETUFSOltETUEgUmVhZF0KPiA+IFJl cXVlc3QgZGV2aWNlIFswMDAwOjAwOjAyLjBdIGZhdWx0IGFkZHIgMzliNTg0NTAwMCwgaW9tbXUg cmVnID0KPiA+IGZmZmY4MmMwMDAyMWQwMDAKPiA+IE9jdCAxNCAxODo0MTo0OS4wNTY1OTQgVk0g aHlwZXJ2aXNvcjogKFhFTikgW1ZULURdRE1BUjogcmVhc29uIDA2IC0KPiA+IFBURSBSZWFkIGFj Y2VzcyBpcyBub3Qgc2V0Cj4gPiBPY3QgMTQgMTg6NDE6NDkuMDU2Nzg0IGtlcm5lbDpbICAgODUu NTcwNjY4XSBbZHJtOmdlbjhfZGVfaXJxX2hhbmRsZXIKPiA+IFtpOTE1XV0gKkVSUk9SKiBGYXVs dCBlcnJvcnMgb24gcGlwZSBBOiAweDAwMDAwMDgwCj4gPiBPY3QgMTQgMTg6NDE6NDkuMDU2Nzg5 IGtlcm5lbDpbICAgODUuNTcwNjg3XSBbZHJtOmdlbjhfZGVfaXJxX2hhbmRsZXIKPiA+IFtpOTE1 XV0gKkVSUk9SKiBGYXVsdCBlcnJvcnMgb24gcGlwZSBBOiAweDAwMDAwMDgwCj4gPiBPY3QgMTQg MTg6NDE6NDkuMDU2ODg1IFZNIGh5cGVydmlzb3I6IChYRU4pIFtWVC1EXURNQVI6W0RNQSBSZWFk XQo+ID4gUmVxdWVzdCBkZXZpY2UgWzAwMDA6MDA6MDIuMF0gZmF1bHQgYWRkciA0MjM4ZDBhMDAw LCBpb21tdSByZWcgPQo+ID4gZmZmZjgyYzAwMDIxZDAwMAo+ID4gT2N0IDE0IDE4OjQxOjQ5LjA1 Njg5MCBWTSBoeXBlcnZpc29yOiAoWEVOKSBbVlQtRF1ETUFSOiByZWFzb24gMDYgLQo+ID4gUFRF IFJlYWQgYWNjZXNzIGlzIG5vdCBzZXQKPiA+Cj4gPiBUaGV5IHJlcGVhdC4gSW4gdGhlIGxvZyBh dHRhY2hlZCB0bwo+ID4gaHR0cHM6Ly9naXRsYWIuZnJlZWRlc2t0b3Aub3JnL2RybS9pbnRlbC8t L2lzc3Vlcy8yNTc2LCB0aGV5IHN0YXJ0IGF0Cj4gPiAiT2N0IDE0IDE4OjQxOjQ5LjA1NjU4OSIg YW5kIGNvbnRpbnVlIHVudGlsIEkgdW5wbHVnIHRoZSBkb2NrIGFyb3VuZAo+ID4gIk9jdCAxNCAx ODo0MTo1NC44MDE4MDIiLgo+ID4KPiA+IEkndmUgYWxzbyBzZWVuIHNpbWlsYXIgbWVzc2FnZXMg d2hlbiBhdHRhY2hpbmcgdGhlIGxhcHRvcCdzIEhETUkgcG9ydAo+ID4gdG8gYSA0ayBtb25pdG9y LiBUaGUgZURQIGRpc3BsYXkgYnkgaXRzZWxmIHNlZW1zIG9rYXkuCj4gPgo+ID4gSSB0cmllZCBG ZWRvcmEgMzEgJiAzMiBsaXZlIGltYWdlcyB3aXRoIGludGVsX2lvbW11PW9uLCBzbyBubyBYZW4s IGFuZAo+ID4gZGlkbid0IHNlZSBhbnkgZXJyb3JzCj4gPgo+ID4gVGhpcyBpcyBhIGtlcm5lbCAm IHhlbiBsb2cgd2l0aCBkcm0uZGVidWc9MHgxZS4gSXQgYWxzbyBpbmNsdWRlcyBzb21lCj4gPiBh cHBsaWNhdGlvbiAoZ2xhc3MpIGxvZ2dpbmcgd2hlbiBpdCBjaGFuZ2VzIHJlc29sdXRpb25zIHdo aWNoIHNlZW1zIHRvCj4gPiBzZXQgb2ZmIHRoZSBETUEgZmF1bHRzLiA1NTAwLWlnZngtbWVzc2Fn ZXMta2Vybi14ZW4tZ2xhc3MKPiA+Cj4gPiBSdW5uaW5nIHhlbiB3aXRoIGlvbW11PW5vLWlnZngg ZGlzYWJsZXMgdGhlIGlvbW11IGZvciB0aGUgaTkxNQo+ID4gZ3JhcGhpY3MgYW5kIG5vIGZhdWx0 cyBhcmUgcmVwb3J0ZWQuIEhvd2V2ZXIsIHRoYXQgYnJlYWtzIHNvbWUgb3RoZXIKPiA+IGRldmlj ZXMgKERlbGwgTGF0aXR1ZGUgNzIwMCBhbmQgNTU4MCkgZ2l2aW5nIGEgYmxhY2sgc2NyZWVuIHdp dGg6Cj4gPgo+ID4gT2N0IDEwIDEzOjI0OjM3LjAyMjExNyBrZXJuZWw6WyAgIDE0Ljg4NDc1OV0g aTkxNSAwMDAwOjAwOjAyLjA6IEZhaWxlZAo+ID4gdG8gaWRsZSBlbmdpbmVzLCBkZWNsYXJpbmcg d2VkZ2VkIQo+ID4gT2N0IDEwIDEzOjI0OjM3LjAyMjExOCBrZXJuZWw6WyAgIDE0Ljk2NDc5NF0g aTkxNSAwMDAwOjAwOjAyLjA6IEZhaWxlZAo+ID4gdG8gaW5pdGlhbGl6ZSBHUFUsIGRlY2xhcmlu ZyBpdCB3ZWRnZWQhCj4gPgo+ID4gQW55IHN1Z2dlc3Rpb25zIHdlbGNvbWUuCj4gCj4gUHJlc3Vt YWJseSB0aGlzIGlzIHdpdGggYSBQViBkb20wLsKgIFdoYXQgYXJlIDM5YjU4NDUwMDAgYW5kIDQy MzhkMGEwMDAKPiBpbiB0aGUgbWFjaGluZSBtZW1vcnkgbWFwPwo+IAo+IFRoaXMgc21lbGxzIGxp a2UgYSBtaXNzaW5nIFJNUlIgaW4gdGhlIEFDUEkgdGFibGVzLgoKSSBhZ3JlZS4KCkNhbiB5b3Ug cGFzdGUgdGhlIG1lbW9yeSBtYXAgYXMgcHJpbnRlZCBieSBYZW4gd2hlbiBib290aW5nLCBhbmQg d2hhdApjb21tYW5kIGxpbmUgYXJlIHlvdSB1c2luZyB0byBib290IFhlbi4KCkhhdmUgeW91IHRy aWVkIGFkZGluZyBkb20wLWlvbW11PW1hcC1pbmNsdXNpdmUgdG8gdGhlIFhlbiBjb21tYW5kCmxp bmU/CgpSb2dlci4KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X18KSW50ZWwtZ2Z4IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3Jn Cmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4 Cg== 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 X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4A02C433E7 for ; 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d="scan'208";a="29314360" Date: Thu, 15 Oct 2020 13:31:33 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jason Andryuk CC: Andrew Cooper , , xen-devel Subject: Re: i915 dma faults on Xen Message-ID: <20201015113109.GA68032@Air-de-Roger> References: <1a3b90f4-564e-84d3-fd6a-3454e8753579@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1a3b90f4-564e-84d3-fd6a-3454e8753579@citrix.com> X-ClientProxiedBy: AMSPEX02CAS02.citrite.net (10.69.22.113) To FTLPEX02CL06.citrite.net (10.13.108.179) On Wed, Oct 14, 2020 at 08:37:06PM +0100, Andrew Cooper wrote: > On 14/10/2020 20:28, Jason Andryuk wrote: > > Hi, > > > > Bug opened at https://gitlab.freedesktop.org/drm/intel/-/issues/2576 > > > > I'm seeing DMA faults for the i915 graphics hardware on a Dell > > Latitude 5500. These were captured when I plugged into a Dell > > Thunderbolt dock with two DisplayPort monitors attached. Xen 4.12.4 > > staging and Linux 5.4.70 (and some earlier versions). > > > > Oct 14 18:41:49.056490 kernel:[ 85.570347] [drm:gen8_de_irq_handler > > [i915]] *ERROR* Fault errors on pipe A: 0x00000080 > > Oct 14 18:41:49.056494 kernel:[ 85.570395] [drm:gen8_de_irq_handler > > [i915]] *ERROR* Fault errors on pipe A: 0x00000080 > > Oct 14 18:41:49.056589 VM hypervisor: (XEN) [VT-D]DMAR:[DMA Read] > > Request device [0000:00:02.0] fault addr 39b5845000, iommu reg = > > ffff82c00021d000 > > Oct 14 18:41:49.056594 VM hypervisor: (XEN) [VT-D]DMAR: reason 06 - > > PTE Read access is not set > > Oct 14 18:41:49.056784 kernel:[ 85.570668] [drm:gen8_de_irq_handler > > [i915]] *ERROR* Fault errors on pipe A: 0x00000080 > > Oct 14 18:41:49.056789 kernel:[ 85.570687] [drm:gen8_de_irq_handler > > [i915]] *ERROR* Fault errors on pipe A: 0x00000080 > > Oct 14 18:41:49.056885 VM hypervisor: (XEN) [VT-D]DMAR:[DMA Read] > > Request device [0000:00:02.0] fault addr 4238d0a000, iommu reg = > > ffff82c00021d000 > > Oct 14 18:41:49.056890 VM hypervisor: (XEN) [VT-D]DMAR: reason 06 - > > PTE Read access is not set > > > > They repeat. In the log attached to > > https://gitlab.freedesktop.org/drm/intel/-/issues/2576, they start at > > "Oct 14 18:41:49.056589" and continue until I unplug the dock around > > "Oct 14 18:41:54.801802". > > > > I've also seen similar messages when attaching the laptop's HDMI port > > to a 4k monitor. The eDP display by itself seems okay. > > > > I tried Fedora 31 & 32 live images with intel_iommu=on, so no Xen, and > > didn't see any errors > > > > This is a kernel & xen log with drm.debug=0x1e. It also includes some > > application (glass) logging when it changes resolutions which seems to > > set off the DMA faults. 5500-igfx-messages-kern-xen-glass > > > > Running xen with iommu=no-igfx disables the iommu for the i915 > > graphics and no faults are reported. However, that breaks some other > > devices (Dell Latitude 7200 and 5580) giving a black screen with: > > > > Oct 10 13:24:37.022117 kernel:[ 14.884759] i915 0000:00:02.0: Failed > > to idle engines, declaring wedged! > > Oct 10 13:24:37.022118 kernel:[ 14.964794] i915 0000:00:02.0: Failed > > to initialize GPU, declaring it wedged! > > > > Any suggestions welcome. > > Presumably this is with a PV dom0.  What are 39b5845000 and 4238d0a000 > in the machine memory map? > > This smells like a missing RMRR in the ACPI tables. I agree. Can you paste the memory map as printed by Xen when booting, and what command line are you using to boot Xen. Have you tried adding dom0-iommu=map-inclusive to the Xen command line? Roger.