Alex Bennée <alex.ben...@linaro.org> writes: (doh, replying to virglrender-devel thanks to autocomplete failure)
> Hi, > > I'm trying to get an understanding of the blob allocation and mapping > flow for virtio-gpu for Vulkan and Rutabaga. Having gotten all the > various libraries setup I'm still seeing failures when running a TCG > guest (buildroot + latest glm, mesa, vkmark) with: > > ./qemu-system-aarch64 \ > -M virt -cpu cortex-a76 \ > -m 8192 \ > -object memory-backend-memfd,id=mem,size=8G,share=on \ > -serial mon:stdio \ > -kernel > ~/lsrc/linux.git/builds/arm64.initramfs/arch/arm64/boot/Image \ > -append "console=ttyAMA0" \ > -device virtio-gpu-gl,context_init=true,blob=true,hostmem=4G \ > -display sdl,gl=on -d > guest_errors,trace:virtio_gpu_cmd_res\*,trace:virtio_gpu_virgl_process_command > -D debug.log > > which shows up as detected in dmesg but not to vulkaninfo: > > [ 0.644879] virtio-pci 0000:00:01.0: enabling device (0000 -> 0003) > > [ 0.648643] virtio-pci 0000:00:02.0: enabling device (0000 -> 0002) > [ 0.672391] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled > > > [ 0.678071] Serial: AMBA driver > > [ 0.682122] [drm] pci: virtio-gpu-pci detected at 0000:00:02.0 > [ 0.683249] [drm] Host memory window: 0x8000000000 +0x100000000 > [ 0.683420] [drm] features: +virgl +edid +resource_blob +host_visible > [ 0.683470] [drm] features: +context_init > > > [ 0.695695] [drm] number of scanouts: 1 > > [ 0.695837] [drm] number of cap sets: 3 > > [ 0.716173] [drm] cap set 0: id 1, max-version 1, max-size 308 > [ 0.716499] [drm] cap set 1: id 2, max-version 2, max-size 1384 > [ 0.716686] [drm] cap set 2: id 4, max-version 0, max-size 160 > > > [ 0.726001] [drm] Initialized virtio_gpu 0.1.0 0 for 0000:00:02.0 on > minor 0 > virgl_resource_create: err=0, res=2 > > virgl_renderer_resource_attach_iov: 0x55b843c17a80/2 > > virgl_resource_attach_iov: pipe_resource: 0x55b8434da8f0 > > vrend_pipe_resource_attach_iov: 0x43 > > ... > > # vulkaninfo --summary > WARNING: [Loader Message] Code 0 : terminator_CreateInstance: Failed to > CreateInstance in ICD 1. Skipping ICD. > error: XDG_RUNTIME_DIR is invalid or not set in the environment. > ========== > VULKANINFO > ========== > > Vulkan Instance Version: 1.3.262 > > > Instance Extensions: count = 12 > ------------------------------- > VK_EXT_debug_report : extension revision 10 > VK_EXT_debug_utils : extension revision 2 > VK_KHR_device_group_creation : extension revision 1 > VK_KHR_external_fence_capabilities : extension revision 1 > VK_KHR_external_memory_capabilities : extension revision 1 > VK_KHR_external_semaphore_capabilities : extension revision 1 > VK_KHR_get_physical_device_properties2 : extension revision 2 > VK_KHR_get_surface_capabilities2 : extension revision 1 > VK_KHR_portability_enumeration : extension revision 1 > VK_KHR_surface : extension revision 25 > VK_KHR_surface_protected_capabilities : extension revision 1 > VK_LUNARG_direct_driver_loading : extension revision 1 > > Instance Layers: > ---------------- > > Devices: > ======== > GPU0: > apiVersion = 1.3.267 > driverVersion = 0.0.1 > vendorID = 0x10005 > deviceID = 0x0000 > deviceType = PHYSICAL_DEVICE_TYPE_CPU > deviceName = llvmpipe (LLVM 15.0.3, 128 bits) > driverID = DRIVER_ID_MESA_LLVMPIPE > driverName = llvmpipe > driverInfo = Mesa 23.3.2 (LLVM 15.0.3) > conformanceVersion = 1.3.1.1 > deviceUUID = 6d657361-3233-2e33-2e32-000000000000 > driverUUID = 6c6c766d-7069-7065-5555-494400000000 > > With an older and more hacked up set of the blob patches I can get > vulkaninfo to work but I see multiple GPUs and vkmark falls over when > mapping stuff: > > # vulkaninfo --summary > render_state_create_resource: res_id = 5 > vkr_context_add_resource: res_id = 5 > vkr_context_import_resource_internal: res_id = 5 > virgl_resource_create: err=0, res=5 > > render_state_create_resource: res_id = 6 > > vkr_context_add_resource: res_id = 6 > > vkr_context_import_resource_internal: res_id = 6 > virgl_resource_create: err=0, res=6 > error: XDG_RUNTIME_DIR is invalid or not set in the environment. > ========== > > VULKANINFO > > ========== > > Vulkan Instance Version: 1.3.262 > > > Instance Extensions: count = 12 > > ------------------------------- > > VK_EXT_debug_report : extension revision 10 > VK_EXT_debug_utils : extension revision 2 > VK_KHR_device_group_creation : extension revision 1 > VK_KHR_external_fence_capabilities : extension revision 1 > VK_KHR_external_memory_capabilities : extension revision 1 > VK_KHR_external_semaphore_capabilities : extension revision 1 > VK_KHR_get_physical_device_properties2 : extension revision 2 > VK_KHR_get_surface_capabilities2 : extension revision 1 > VK_KHR_portability_enumeration : extension revision 1 > VK_KHR_surface : extension revision 25 > VK_KHR_surface_protected_capabilities : extension revision 1 > VK_LUNARG_direct_driver_loading : extension revision 1 > VK_LUNARG_direct_driver_loading : extension revision 1 > > [0/7869] > > Instance Layers: > ---------------- > > Devices: > ======== > GPU0: > apiVersion = 1.3.230 > driverVersion = 23.3.4 > vendorID = 0x8086 > deviceID = 0xa780 > deviceType = PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU > deviceName = Virtio-GPU Venus (Intel(R) Graphics (RPL-S)) > driverID = DRIVER_ID_MESA_VENUS > driverName = venus > driverInfo = Mesa 23.3.4 > conformanceVersion = 1.3.0.0 > deviceUUID = 29d2e940-a1a0-3054-0f9a-9f7dec52a084 > driverUUID = b11fafe9-8706-9ab8-0f16-8b272cf893ca > GPU1: > apiVersion = 1.2.0 > driverVersion = 23.3.4 > vendorID = 0x10005 > deviceID = 0x0000 > deviceType = PHYSICAL_DEVICE_TYPE_CPU > deviceName = Virtio-GPU Venus (llvmpipe (LLVM 15.0.6, 256 > bits)) > driverID = DRIVER_ID_MESA_VENUS > driverName = venus > driverInfo = Mesa 23.3.4 > conformanceVersion = 1.3.0.0 > deviceUUID = 5fb5c03f-c537-f0fe-a7e6-9cd5866acb8d > driverUUID = b11fafe9-8706-9ab8-0f16-8b272cf893ca > GPU2: > apiVersion = 1.3.267 > driverVersion = 0.0.1 > vendorID = 0x10005 > deviceID = 0x0000 > deviceType = PHYSICAL_DEVICE_TYPE_CPU > deviceName = llvmpipe (LLVM 15.0.3, 128 bits) > driverID = DRIVER_ID_MESA_LLVMPIPE > driverName = llvmpipe > driverInfo = Mesa 23.3.2 (LLVM 15.0.3) > conformanceVersion = 1.3.1.1 > deviceUUID = 6d657361-3233-2e33-2e32-000000000000 > driverUUID = 6c6c766d-7069-7065-5555-494400000000 > render_state_destroy_resource: res_id = 5 > vkr_context_remove_resource: res_id = 5 > virgl_resource_destroy_func: res=5 > render_state_destroy_resource: res_id = 6 > vkr_context_remove_resource: res_id = 6 > virgl_resource_destroy_func: res=6 > > running vkmark gives: > > # vkmark --winsys kms > render_state_create_resource: res_id = 7 > vkr_context_add_resource: res_id = 7 > vkr_context_import_resource_internal: res_id = 7 > virgl_resource_create: err=0, res=7 > render_state_create_resource: res_id = 8 > vkr_context_add_resource: res_id = 8 > vkr_context_import_resource_internal: res_id = 8 > virgl_resource_create: err=0, res=8 > virgl_resource_create: err=0, res=9 > virgl_renderer_resource_attach_iov: 0x55615acf7f40/9 > virgl_resource_attach_iov: pipe_resource: 0x55615acf7db0 > vrend_pipe_resource_attach_iov: 0x43 > > this bit does nothing as VREND_STORAGE_HOST_SYSTEM_MEMORY isn't set. > > virgl_resource_create: err=0, res=10 > virgl_renderer_resource_attach_iov: 0x55615ae569a0/10 > virgl_resource_attach_iov: pipe_resource: 0x55615a99ce20 > vrend_pipe_resource_attach_iov: 0x43 > Warning: KMSWindowSystem: Using VK_IMAGE_TILING_OPTIMAL for dmabuf with > invalid modifier, but this is not guaranteed to work. > vkr_dispatch_vkAllocateMemory: mem_index_type:0 > virgl_render_server[2889817]: vkr: failed to import resource: invalid > res_id 9 > virgl_render_server[2889817]: vkr: vkAllocateMemory resulted in CS error > virgl_render_server[2889817]: vkr: ring_submit_cmd: vn_dispatch_command > failed > MESA-VIRTIO: debug: vn_ring_submit abort on fatal > render_state_destroy_resource: res_id = 7 > vkr_context_remove_resource: res_id = 7 > render_state_destroy_resource: res_id = 8 > vkr_context_remove_resource: res_id = 8 > virgl_resource_destroy_func: res=7 > virgl_resource_destroy_func: res=8 > virgl_resource_destroy_func: res=10 > virgl_resource_destroy_func: res=9 > Aborted > > The debug printfs are throughout QEMU and virlgrenderer while trying to > work out what was going on. While the eventual aim is to enable this > stack on a ARM64 platform with Xen I wanted to make sure I understand > the blob resource flow first. > > As I understand it we need resource blobs to hold 3D data for rendering > that is visible to the underlying GPU that will be doing the work. While > these blobs can be copied back and forth the most efficient way to do > this is to allocate HOST VISIBLE blobs that are appropriately placed > and aligned for the host GPU. For Vulkan there will also be the command > stream which will need to be translated from the Vulkan's portable > shader IR (as emitted by mesa on the guest) to the underlying shader > commands on the host system (via mesa on the host). > > I can see the host visible region is created as a large chunk of the PCI > BAR space and is outside of the guests system RAM. > > The guest creates a unique resource ID by submitting a > VIRTIO_GPU_CMD_RESOURCE_CREATE_BLOB command. > > Q1: is the actual allocation done here? I assume this happens somewhere > in the depths of virglrenderer or is it the kernel DRM subsystem? > > Q2: should the memory for this resource be visible to the host > userspace at this point? Where is the mapping into userspace done? > > The guest submits a VIRTIO_GPU_CMD_RESOURCE_MAP_BLOB command with a > unique resource ID and requests it is mapped at an offset into the host > visible memory region. > > Q3: Is all the mapping for host and guest handled by QEMU's memory_region > code? > > Q4: Are there any differences between cards with VRAM and those with a > unified memory architecture (e.g. using system RAM)? > > Finally should we expect to see any other resources > (RESOURCE_CREATE_2D/3D, TRANSFER_TO_HOST, ATTACH_BACKING) if we have > host visible blobs properly allocated and working? -- Alex Bennée Virtualisation Tech Lead @ Linaro