Jordan Callicoat JCallicoat

QEMU with VirtIO GPU Vulkan Support

With its latest reales qemu added the Venus patches so that virtio-gpu now support venus encapsulation for vulkan. This is one more piece to the puzzle towards full Vulkan support.

An outdated blog post on clollabora described in 2021 how to enable 3D acceleration of Vulkan applications in QEMU through the Venus experimental Vulkan driver for VirtIO-GPU with a local development environment. Following up on the outdated write up, this is how its done today.

Definitions

Let's start with the brief description of the projects mentioned in the post & extend them:

VirGL for Linux KVM guests on Ubuntu Desktop

NOTE: Please don't ask for help here, it was a miracle that I got it to work at all. Seek answers in the usual places (yes, even Stackoverflow knows more than I do).

The question: How can I get 3d accelerated graphics for Linux guests in KVM without using PCI passthrough?

The short answer is: Use VirGL. The long answer is more complicated, because the VirGL project has had slow but steady progress towards actually working reliably, but the degree to which any given Linux distribution (or related driver project) is in sync has varied greatly over time. Even if it works right now, today, on your machine, it might not tomorrow. Note that even when it works, graphics performance is mediocre to downright painful.

Tested on Ubuntu Desktop 22.04.04 LTS with qemu-kvm, in an "Ubuntu on Xorg" session (not Wayland). Linux quests must have spice-vdagent installed (Ubuntu installs this by default). The hardware is a AMD 5600G d

FAQ on the xz-utils backdoor (CVE-2024-3094)

This is a living document. Everything in this document is made in good faith of being accurate, but like I just said; we don't yet know everything about what's going on.

Update: I've disabled comments as of 2025-01-26 to avoid everyone having notifications for something a year on if someone wants to suggest a correction. Folks are free to email to suggest corrections still, of course.

Background

Adding Fancy Tag Switch Effects In AwesomeWM

Before We Begin

First of all, you need to have AwesomeWM installed and running. I'm using awesome-git, the development release. I'm not sure whether this would work on the stable release.

Negative Python user experience on Debian/Ubuntu

The user experience of Python on a minimal Debian or Ubuntu installation is bad. Core features like virtual environments, pip bootstrapping, and the ssl module are either missing or do not work like designed and documented. Some Python core developers including me are worried and consider Debian/Ubuntu's packaging harmful for Python's reputation and branding. Users don't get what they expect.

Reproducer

The problems can be easily reproduced with official Debian and Ubuntu containers in Docker or Podman. Debian Stable (Debian 10 Buster) comes with Python 3.7.3. Ubuntu Focal (20.04 LTS) has Python 3.8.5.

Run Debian container

Think twice before abandoning X11. Wayland breaks everything!

Wayland breaks everything! It is binary incompatible, provides no clear transition path with 1:1 replacements for everything in X11, and is even philosophically incompatible with X11. Hence, if you are interested in existing applications to "just work" without the need for adjustments, then you may be better off avoiding Wayland.

Wayland solves no issues I have but breaks almost everything I need. Even the most basic, most simple things (like xkill) - in this case with no obvious replacement. And usually it stays broken, because the Wayland folks mostly seem to care about Automotive, Gnome, maybe KDE - and alienating everyone else (e.g., people using just an X11 window manager or something like GNUstep) in the process.

	// ==UserScript==
	// @name GitHub: remove `?tab=readme-ov-file` from URL
	// @description GitHub: remove `?tab=readme-ov-file` from URL
	// @namespace https://gist.github.com/vogler
	// @downloadURL https://gist.github.com/vogler/74edff6de37c3a13eeff8c99c6bed910/raw/clean-url-readme-tab.github.com.tamper.js
	// @version 0.1
	// @author Ralf Vogler
	// @match https://github.com/*
	// @icon https://www.google.com/s2/favicons?sz=64&domain=github.com
	// @grant none

	"""
	MIT License

	Copyright (c) 2023 David Buchanan

	Permission is hereby granted, free of charge, to any person obtaining a copy
	of this software and associated documentation files (the "Software"), to deal
	in the Software without restriction, including without limitation the rights
	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	copies of the Software, and to permit persons to whom the Software is

	#! /bin/sh

	# the metadata only contains the name of the default sink
	default_sink_name=$(pw-metadata 0 'default.audio.sink' \| grep 'value' \| sed "s/.* value:'//;s/' type:.*$//;" \| jq .name)
	default_sink_id=$(pw-dump Node Device \| jq '.[].info.props\|select(."node.name" == '" $default_sink_name "') \| ."object.id"')
	current_volume=$(pw-cli enum-params "$default_sink_id" 'Props' \| grep -A 2 'Spa:Pod:Object:Param:Props:channelVolumes' \| awk '/Float / {gsub(/.*Float\s/," "); print $1^(1/3) }')
	change="${1:-0.1}" # defaults to increment of 0.1
	new_volume=$(echo "$current_volume $change" \| awk '{printf "%f", $1 + $2}')
	# we need to reconvert to cubic root
	#new_volume_cube=$(echo "$new_volume" \| awk '{ print $1^3 }')