Commit Graph

2 Commits

Author SHA1 Message Date
Cong Liu
9d9ae0f07b virtio-gpu-rutabaga: Add empty interface to fix arm64 crash
Add an empty element to the interfaces array, which is consistent with
the behavior of other devices in qemu and fixes the crash on arm64.

0  0x0000fffff5c18550 in  () at /usr/lib64/libc.so.6
1  0x0000fffff6c9cd6c in g_strdup () at /usr/lib64/libglib-2.0.so.0
2  0x0000aaaaab4945d8 in g_strdup_inline (str=<optimized out>) at /usr/include/glib-2.0/glib/gstrfuncs.h:321
3  type_new (info=info@entry=0xaaaaabc1b2c8 <virtio_gpu_rutabaga_pci_info>) at ../qom/object.c:133
4  0x0000aaaaab494f14 in type_register_internal (info=0xaaaaabc1b2c8 <virtio_gpu_rutabaga_pci_info>) at ../qom/object.c:143
5  type_register (info=0xaaaaabc1b2c8 <virtio_gpu_rutabaga_pci_info>) at ../qom/object.c:152
6  type_register_static (info=0xaaaaabc1b2c8 <virtio_gpu_rutabaga_pci_info>) at ../qom/object.c:157
7  type_register_static_array (infos=<optimized out>, nr_infos=<optimized out>) at ../qom/object.c:165
8  0x0000aaaaab6147e8 in module_call_init (type=type@entry=MODULE_INIT_QOM) at ../util/module.c:109
9  0x0000aaaaab10a0ec in qemu_init_subsystems () at ../system/runstate.c:817
10 0x0000aaaaab10d334 in qemu_init (argc=13, argv=0xfffffffff198) at ../system/vl.c:2760
11 0x0000aaaaaae4da6c in main (argc=<optimized out>, argv=<optimized out>) at ../system/main.c:47

Signed-off-by: Cong Liu <liucong2@kylinos.cn>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231031012515.15504-1-liucong2@kylinos.cn>
2023-11-06 14:25:30 +04:00
Gurchetan Singh
1dcc6adbc1 gfxstream + rutabaga: add initial support for gfxstream
This adds initial support for gfxstream and cross-domain.  Both
features rely on virtio-gpu blob resources and context types, which
are also implemented in this patch.

gfxstream has a long and illustrious history in Android graphics
paravirtualization.  It has been powering graphics in the Android
Studio Emulator for more than a decade, which is the main developer
platform.

Originally conceived by Jesse Hall, it was first known as "EmuGL" [a].
The key design characteristic was a 1:1 threading model and
auto-generation, which fit nicely with the OpenGLES spec.  It also
allowed easy layering with ANGLE on the host, which provides the GLES
implementations on Windows or MacOS enviroments.

gfxstream has traditionally been maintained by a single engineer, and
between 2015 to 2021, the goldfish throne passed to Frank Yang.
Historians often remark this glorious reign ("pax gfxstreama" is the
academic term) was comparable to that of Augustus and both Queen
Elizabeths.  Just to name a few accomplishments in a resplendent
panoply: higher versions of GLES, address space graphics, snapshot
support and CTS compliant Vulkan [b].

One major drawback was the use of out-of-tree goldfish drivers.
Android engineers didn't know much about DRM/KMS and especially TTM so
a simple guest to host pipe was conceived.

Luckily, virtio-gpu 3D started to emerge in 2016 due to the work of
the Mesa/virglrenderer communities.  In 2018, the initial virtio-gpu
port of gfxstream was done by Cuttlefish enthusiast Alistair Delva.
It was a symbol compatible replacement of virglrenderer [c] and named
"AVDVirglrenderer".  This implementation forms the basis of the
current gfxstream host implementation still in use today.

cross-domain support follows a similar arc.  Originally conceived by
Wayland aficionado David Reveman and crosvm enjoyer Zach Reizner in
2018, it initially relied on the downstream "virtio-wl" device.

In 2020 and 2021, virtio-gpu was extended to include blob resources
and multiple timelines by yours truly, features gfxstream/cross-domain
both require to function correctly.

Right now, we stand at the precipice of a truly fantastic possibility:
the Android Emulator powered by upstream QEMU and upstream Linux
kernel.  gfxstream will then be packaged properfully, and app
developers can even fix gfxstream bugs on their own if they encounter
them.

It's been quite the ride, my friends.  Where will gfxstream head next,
nobody really knows.  I wouldn't be surprised if it's around for
another decade, maintained by a new generation of Android graphics
enthusiasts.

Technical details:
  - Very simple initial display integration: just used Pixman
  - Largely, 1:1 mapping of virtio-gpu hypercalls to rutabaga function
    calls

Next steps for Android VMs:
  - The next step would be improving display integration and UI interfaces
    with the goal of the QEMU upstream graphics being in an emulator
    release [d].

Next steps for Linux VMs for display virtualization:
  - For widespread distribution, someone needs to package Sommelier or the
    wayland-proxy-virtwl [e] ideally into Debian main. In addition, newer
    versions of the Linux kernel come with DRM_VIRTIO_GPU_KMS option,
    which allows disabling KMS hypercalls.  If anyone cares enough, it'll
    probably be possible to build a custom VM variant that uses this display
    virtualization strategy.

[a] https://android-review.googlesource.com/c/platform/development/+/34470
[b] https://android-review.googlesource.com/q/topic:%22vulkan-hostconnection-start%22
[c] https://android-review.googlesource.com/c/device/generic/goldfish-opengl/+/761927
[d] https://developer.android.com/studio/releases/emulator
[e] https://github.com/talex5/wayland-proxy-virtwl

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Alyssa Ross <hi@alyssa.is>
Tested-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
Tested-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Antonio Caggiano <quic_acaggian@quicinc.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
2023-10-16 11:29:56 +04:00