** Description changed:

  -- Description --
  
  This Feature Freeze Exception request proposes enabling and shipping
  video acceleration support in virglrenderer for Ubuntu Resolute 26.04.
  This change would improve hardware-accelerated video decode/encode
  support for virtualized graphics workloads (notably QEMU/KVM guests
  using virtio-gpu), bringing Ubuntu in line with upstream capabilities
  and improving performance for desktop and media use cases.
  
  The video support was disabled for Ubuntu (Ubuntu delta) because libva is
  in universe
  (libva is a dependency of virglrenderer when video acceleration is enabled)
  
  But libva is now in main as part of :
  https://bugs.launchpad.net/ubuntu/+source/libva/+bug/2097800
  
  -- Rationale / Benefit ---
  
  virglrenderer is used to provide accelerated OpenGL rendering for
  virtual machines via the virtio-gpu stack. Upstream has added support
  for video acceleration APIs (such as VA-API / Vulkan Video interop,
  depending on host capabilities), allowing guest workloads to offload
  video decode/encode to the host GPU.
  
  Enabling this support would:
  
   - Improve playback smoothness for high-resolution video.
   - Reduce guest CPU overhead.
   - Improve user experience for desktop VM users.
   - Better support developer and CI workflows using graphical guests.
  
  -- Builds ---
  
  PPA: https://launchpad.net/~hectorcao/+archive/ubuntu/lp2141692
  
  -- Test ---
- Run the binary: /usr/bin/virgl_test_server
+ 
+ Ideally; we need a compatible QEMU to test the video accel feature of 
virglrenderer and QEMU does not provide this support yet (neither in upstream
+ nor Ubuntu)
+ 
+ One simpler way to test if we regress on anything with this addition is
+ to run the use the binary the simulate a server providing virglrenderer
+ 
+  /usr/bin/virgl_test_server
+ 
  
  -- Seed ---
  
  seeded-in-ubuntu virglrenderer
  libvirglrenderer-dev (from virglrenderer) is seeded in:
    ubuntu-budgie: supported
    ubuntu: supported
  
  -- Additional information ---
  
  Despite the fact that we enable video accel for virglrenderer, to enable this 
feature for VMs in Ubuntu, we need to enable it in QEMU where virglrenderer init
  is invoked.
  
  We do not consider to do it for QEMU because it is still in discussion 
upstream
  and we can get it in Resolute via QEMU HWE in the future.
  
  Enabling it for virglrender allows us to anticipate this  QEMU HWE
  upgrade with the video accel capability.
  
  --- Original bug report ---
  
  # Summary
  
  Ubuntu’s virglrenderer package is built with the Meson option for video
  acceleration disabled (-Dvideo=false). This prevents the VirGL video
  path (VA-API encode/decode exposure via virtio-gpu/virgl) from being
  usable on Ubuntu hosts, even when the underlying stack supports it.
  Please enable the feature in Ubuntu builds for the 26.04 cycle by
  switching to -Dvideo=enabled (or equivalent).
  
  # Background / Motivation
  
  VirGL already enables accelerated rendering for virtio-gpu guests.
  Upstream virglrenderer also has an optional video acceleration path
  intended to expose video encode/decode to the guest via VA-API (virtio-
  gpu VA-API driver), which can significantly reduce guest CPU load and
  improve responsiveness for multimedia and remote desktop streaming
  workloads (e.g. “VDI-like” interactive desktops, remote developer
  workstations, training labs).
  
  # Current Ubuntu State (evidence)
  
  1) Ubuntu previously carried an explicit delta to disable video acceleration:
     “Disable video acceleration on Ubuntu until libva gets repromoted.”
     (See Launchpad bug: #2040435)
  
  2) Ubuntu builds still pass -Dvideo=false. For example, in Ubuntu 25.10
  (Questing) virglrenderer 1.1.0-2 build logs show dh_auto_configure
  invoking Meson with -Dvideo=false and reporting “video : false”.
  
  3) The original stated blocker (libva component) appears to have
  changed: libva is published in “main” in Ubuntu 25.10 (Questing). This
  suggests it is worth re-evaluating the continued forced disablement of
  virglrenderer video.
  
  # Request
  
  Please modify Ubuntu’s virglrenderer packaging to enable the Meson video 
feature:
  - Remove the explicit -Dvideo=false override
  - Enable the feature (preferably as a Meson “feature” option: -Dvideo=enabled)
  
  If there are remaining blockers beyond the original libva component
  rationale (e.g., dependency policy, stability/regression concerns,
  security support), please document them in this bug so they can be
  addressed during the 26.04 cycle.
  
  # Notes / Scope
  
  - This bug is specifically about enabling the virglrenderer build
  feature. Runtime enablement may additionally require QEMU to pass
  VIRGL_RENDERER_USE_VIDEO during virgl init. If Ubuntu QEMU does not
  currently set this, that would be a separate (but related) issue;
  enabling the virglrenderer feature is still a necessary prerequisite and
  should be tracked independently.
  
  # Test Plan (for maintainers/testers)
  
  Host (Ubuntu):
  
  1) Build/install virglrenderer with Meson video enabled.
  2) Run a VM with virtio-gpu + virgl/virtio-gl enabled (virt-manager “3D 
acceleration” / OpenGL).
  Guest (Ubuntu):
  3) Install libva-utils and run:
     LIBVA_DRIVER_NAME=virtio_gpu vainfo
  Expected:
  - virtio_gpu VA-API driver loads
  - Additional codec profiles (decode/encode depending on host capabilities) 
appear compared to stock Ubuntu build
  
  # Impact
  
  Enabling this feature can:
  - Reduce CPU use in guests for video encode/decode workloads (where supported)
  - Improve “desktop-as-video” remote desktop performance when streaming 
solutions inside the guest can use VA-API encode
  - Improve Ubuntu’s competitiveness for GPU-accelerated VM desktop/VDI-like 
scenarios
  
  # References
  
  - LP: #2040435 (Ubuntu delta mentions disabling video acceleration until 
libva repromotion)
  - Questing virglrenderer build logs show -Dvideo=false (“video : false”)
  - libva is published in “main” in Questing (component change vs Noble)

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https://bugs.launchpad.net/bugs/2141692

Title:
  [FFe] Enable VirGL video acceleration in Ubuntu virglrenderer builds
  (Meson -Dvideo=enabled) for 26.04

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