Most of QEMU's PCI display device models, such as: libvirt video/model/@type QEMU -device ------------------------- ------------ cirrus cirrus-vga vga VGA qxl qxl-vga virtio virtio-vga come with a linear framebuffer (sometimes called "VGA compatibility framebuffer"). This linear framebuffer lives in one of the PCI device's MMIO BARs, and allows guest code (primarily: firmware drivers, and non-accelerated OS drivers) to display graphics with direct memory access. Due to architectural reasons on aarch64/KVM hosts, this kind of framebuffer doesn't / can't work in qemu-system-(arm|aarch64) -M virt machines. Cache coherency issues guarantee a corrupted / unusable display. The problem has been researched by several people, including kvm-arm maintainers, and it's been decided that the best way (practically the only way) to have boot time graphics for such guests is to consolidate on QEMU's "virtio-gpu-pci" device.

From <https://bugzilla.redhat.com/show_bug.cgi?id=1195176>, libvirt supports

<devices> <video> <model type='virtio'/> </video> </devices> but libvirt unconditionally maps @type='virtio' to QEMU's "virtio-vga" device model. (See the qemuBuildDeviceVideoStr() function and the "qemuDeviceVideo" enum impl.) According to the above, this is not right for the "virt" machine type; the qemu-system-(arm|aarch64) binaries don't even recognize the "virtio-vga" device model (justifiedly). Whereas "virtio-gpu-pci", which is a pure virtio device without a compatibility framebuffer, is available, and works fine. (The ArmVirtQemu ("AAVMF") platform of edk2 -- that is, the UEFI firmware for "virt" -- supports "virtio-gpu-pci", as of upstream commit 3ef3209d3028. See <https://tianocore.acgmultimedia.com/show_bug.cgi?id=66>.) Override the default mapping of "virtio", from "virtio-vga" to "virtio-gpu-pci", if qemuDomainMachineIsVirt() evaluates to true. Cc: Andrea Bolognani <abologna@redhat.com> Cc: Drew Jones <drjones@redhat.com> Cc: Marc-André Lureau <marcandre.lureau@redhat.com> Suggested-by: Marc-André Lureau <marcandre.lureau@redhat.com> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1372901 Signed-off-by: Laszlo Ersek <lersek@redhat.com> --- src/qemu/qemu_command.c | 4 ++ tests/qemuxml2argvtest.c | 5 +++ tests/qemuxml2xmltest.c | 5 +++ tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.args | 26 +++++++++++ tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.xml | 36 ++++++++++++++++ tests/qemuxml2xmloutdata/qemuxml2xmlout-aarch64-video-virtio-gpu-pci.xml | 45 ++++++++++++++++++++ 6 files changed, 121 insertions(+) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 3a61863b9abb..038c38f2217c 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4325,6 +4325,10 @@ qemuBuildDeviceVideoStr(const virDomainDef *def, virDomainVideoTypeToString(video->type)); goto error; } + if (video->type == VIR_DOMAIN_VIDEO_TYPE_VIRTIO && + qemuDomainMachineIsVirt(def)) { + model = "virtio-gpu-pci"; + } } else { if (video->type != VIR_DOMAIN_VIDEO_TYPE_QXL) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c index dbb0e4d56142..e8540779a4b5 100644 --- a/tests/qemuxml2argvtest.c +++ b/tests/qemuxml2argvtest.c @@ -1872,6 +1872,11 @@ mymain(void) QEMU_CAPS_DEVICE_VIRTIO_RNG, QEMU_CAPS_OBJECT_RNG_RANDOM, QEMU_CAPS_OBJECT_GPEX, QEMU_CAPS_DEVICE_PCI_BRIDGE, QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE, QEMU_CAPS_VIRTIO_SCSI); + DO_TEST("aarch64-video-virtio-gpu-pci", + QEMU_CAPS_NODEFCONFIG, QEMU_CAPS_OBJECT_GPEX, + QEMU_CAPS_DEVICE_PCI_BRIDGE, QEMU_CAPS_DEVICE_IOH3420, + QEMU_CAPS_PCI_MULTIFUNCTION, QEMU_CAPS_DEVICE_VIDEO_PRIMARY, + QEMU_CAPS_DEVICE_VIRTIO_GPU, QEMU_CAPS_BOOTINDEX); DO_TEST("aarch64-aavmf-virtio-mmio", QEMU_CAPS_NODEFCONFIG, QEMU_CAPS_DTB, QEMU_CAPS_DEVICE_VIRTIO_MMIO, diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c index 14c2b0ccf2ce..fb05c8571411 100644 --- a/tests/qemuxml2xmltest.c +++ b/tests/qemuxml2xmltest.c @@ -831,6 +831,11 @@ mymain(void) QEMU_CAPS_DEVICE_VIRTIO_RNG, QEMU_CAPS_OBJECT_RNG_RANDOM, QEMU_CAPS_OBJECT_GPEX, QEMU_CAPS_DEVICE_PCI_BRIDGE, QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE, QEMU_CAPS_VIRTIO_SCSI); + DO_TEST("aarch64-video-virtio-gpu-pci", + QEMU_CAPS_NODEFCONFIG, QEMU_CAPS_OBJECT_GPEX, + QEMU_CAPS_DEVICE_PCI_BRIDGE, QEMU_CAPS_DEVICE_IOH3420, + QEMU_CAPS_PCI_MULTIFUNCTION, QEMU_CAPS_DEVICE_VIDEO_PRIMARY, + QEMU_CAPS_DEVICE_VIRTIO_GPU, QEMU_CAPS_BOOTINDEX); DO_TEST_FULL("aarch64-gic-none", WHEN_BOTH, GIC_NONE, NONE); DO_TEST_FULL("aarch64-gic-none-v2", WHEN_BOTH, GIC_V2, NONE); diff --git a/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.args b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.args new file mode 100644 index 000000000000..56dbdfb66fa2 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.args @@ -0,0 +1,26 @@ +LC_ALL=C \ +PATH=/bin \ +HOME=/home/test \ +USER=test \ +LOGNAME=test \ +QEMU_AUDIO_DRV=none \ +/opt/qemu-installed/bin/qemu-system-aarch64 \ +-name aarch64-vgpu \ +-S \ +-M virt \ +-cpu cortex-a57 \ +-m 1024 \ +-smp 1,sockets=1,cores=1,threads=1 \ +-uuid f3197c89-6457-44fe-b26d-897090ba6541 \ +-nographic \ +-nodefconfig \ +-nodefaults \ +-monitor unix:/tmp/lib/domain--1-aarch64-vgpu/monitor.sock,server,nowait \ +-device ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,\ +addr=0x1 \ +-device ioh3420,port=0x9,chassis=2,id=pci.2,bus=pcie.0,multifunction=on,\ +addr=0x1.0x1 \ +-device virtio-net-pci,vlan=0,id=net0,mac=52:54:00:73:34:53,bus=pci.1,\ +addr=0x0,bootindex=1 \ +-net user,vlan=0,name=hostnet0 \ +-device virtio-gpu-pci,id=video0,bus=pci.2,addr=0x0 diff --git a/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.xml b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.xml new file mode 100644 index 000000000000..4b52a731b043 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-aarch64-video-virtio-gpu-pci.xml @@ -0,0 +1,36 @@ +<domain type='qemu'> + <name>aarch64-vgpu</name> + <uuid>f3197c89-6457-44fe-b26d-897090ba6541</uuid> + <memory unit='KiB'>1048576</memory> + <currentMemory unit='KiB'>1048576</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='aarch64' machine='virt'>hvm</type> + </os> + <features> + <acpi/> + </features> + <cpu mode='custom' match='exact'> + <model fallback='allow'>cortex-a57</model> + </cpu> + <devices> + <emulator>/opt/qemu-installed/bin/qemu-system-aarch64</emulator> + <controller type='pci' index='0' model='pcie-root'/> + <controller type='pci' index='1' model='pcie-root-port'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0' multifunction='on'/> + </controller> + <controller type='pci' index='2' model='pcie-root-port'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1' multifunction='on'/> + </controller> + <interface type='user'> + <mac address='52:54:00:73:34:53'/> + <model type='virtio'/> + <boot order='1'/> + <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/> + </interface> + <video> + <model type='virtio'/> + <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/> + </video> + </devices> +</domain> diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-aarch64-video-virtio-gpu-pci.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-aarch64-video-virtio-gpu-pci.xml new file mode 100644 index 000000000000..26f6a51622ef --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-aarch64-video-virtio-gpu-pci.xml @@ -0,0 +1,45 @@ +<domain type='qemu'> + <name>aarch64-vgpu</name> + <uuid>f3197c89-6457-44fe-b26d-897090ba6541</uuid> + <memory unit='KiB'>1048576</memory> + <currentMemory unit='KiB'>1048576</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='aarch64' machine='virt'>hvm</type> + </os> + <features> + <acpi/> + <gic version='2'/> + </features> + <cpu mode='custom' match='exact'> + <model fallback='allow'>cortex-a57</model> + </cpu> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/opt/qemu-installed/bin/qemu-system-aarch64</emulator> + <controller type='pci' index='0' model='pcie-root'/> + <controller type='pci' index='1' model='pcie-root-port'> + <model name='ioh3420'/> + <target chassis='1' port='0x8'/> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0' multifunction='on'/> + </controller> + <controller type='pci' index='2' model='pcie-root-port'> + <model name='ioh3420'/> + <target chassis='2' port='0x9'/> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1' multifunction='on'/> + </controller> + <interface type='user'> + <mac address='52:54:00:73:34:53'/> + <model type='virtio'/> + <boot order='1'/> + <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/> + </interface> + <video> + <model type='virtio' heads='1' primary='yes'/> + <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/> + </video> + </devices> +</domain> -- 2.9.2