TL;DR: How to get some canonical work-around for quirks into official module and/or kernel repo ? Running with gpu passed through to virtual machine.
----- I'm running this card: 00:06.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Curacao PRO [Radeon R7 370 / R9 270/370 OEM] (prog-if 00 [VGA controller]) passed through to a user domain under Xen. (xen-4.11 release candidate ). I have been running with this patch for a long while now: ----------------------- --- a/drivers/gpu/drm/drm_pci.c 2017-07-30 23:29:43.550000000 +0200 +++ b/drivers/gpu/drm/drm_pci.c 2017-07-30 23:28:55.580000000 +0200 @@ -337,11 +337,28 @@ u32 lnkcap, lnkcap2; *mask = 0; - if (!dev->pdev) - return -EINVAL; - + if (!dev->pdev) { + DRM_INFO("invalid dev->pdev\n"); + return -EINVAL; + } + + if (!dev->pdev->bus) { + DRM_INFO("invalid dev->pdev->bus\n"); + return -EINVAL; + } + + if (!dev->pdev->bus->self) { + DRM_INFO("invalid dev->pdev->bus->self\n"); + return -EINVAL; + } + root = dev->pdev->bus->self; + if (!root->vendor) { + DRM_INFO("invalid root->vendor\n"); + return -EINVAL; + } + /* we've been informed via and serverworks don't make the cut */ if (root->vendor == PCI_VENDOR_ID_VIA || root->vendor == PCI_VENDOR_ID_SERVERWORKS) ------------------------------------------------------ This gets me the following logged on boot: mai 17 23:27:35 gt kernel: [drm] invalid dev->pdev->bus->self I created the patch on a hunch without any knowledge of how that return-value gets interpreted. At the moment I'm using the radeon driver in kernel 4.16.9-gentoo, but I'm thinking about switching to amdgpu. Before I do that I'd hope to have the deficiencies running under Xen could get some kind of "official" work-around. Works OK, but I have some random stalls in window-manager and browsers, without anything showing up in top or atop. One of my suspected culprits is some kind of error time-out in graphics rendering. I'm not a programmer, so wading through threads in gdb is not my forte. _______________________________________________ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx