Files
punktfunk/packaging
enricobuehler 767e67caf4 feat(packaging): grant the host CAP_SYS_NICE, without which the GPU-priority lever does nothing
Wave-2 PW1, second half. The companion commit wires `PYROWAVE_QUEUE_PRIORITY` into the Linux
PyroWave device; this is what makes it work on a packaged host.

Measured on .21 (RTX 5070 Ti, NVIDIA 610.43.02), same binary in both arms:

  as packaged (no capability)     every class refused, REALTIME *and* HIGH -> default priority
  same binary, cap_sys_nice+ep    granted REALTIME on the FIRST attempt, no downgrade

RADV behaves the same way. So this is not the RADV-specific "expect one downgrade to HIGH" the
plan predicted — without the capability there is no elevated priority at all, on any vendor, and
the knob is decoration.

Worth being precise about what is being granted, because it is a network-facing daemon.
CAP_SYS_NICE permits raising scheduling priority (nice, ioprio, affinity, RT class) and nothing
else: no filesystem access, no network privilege, no user switching, and it is NOT setuid. The
repo already ships exactly this capability on its gamescope binary for the same reason. Two side
effects that will otherwise confuse someone debugging: a capability-carrying binary is AT_SECURE,
so the loader ignores LD_LIBRARY_PATH/LD_PRELOAD for it (note this box was propped up by exactly
such a shim during the ffmpeg-9 soname break — that workaround would now be silently ignored), and
core dumps are suppressed by default.

Per packaging path, because none of them are the same:

- Arch: a `_grant_sched_capability` in the scriptlet, called from post_install AND post_upgrade —
  a replaced binary is a new inode, so the capability does not survive an upgrade by itself.
- Debian: the same setcap in the postinst `configure` branch.
- RPM: `%caps(cap_sys_nice=ep)` on the binary in `%files`, which is the rpm-native form — rpm then
  applies it on install, restores it on upgrade, and verifies it. A `%post setcap` does none of
  those.
- NixOS: `security.wrappers`, because a store path is read-only and shared and cannot be setcap'd.
  The unit's ExecStart moves to `config.security.wrapperDir` — without that the wrapper exists and
  the service still runs the uncapped store path, which is the whole failure this fixes.
- Steam Deck: setcap in the installer's sudo block. That box needs it most (one small Van Gogh GPU
  shared between the game and the encode). The binary lives under $HOME, so unlike the /etc
  drop-ins it survives a SteamOS A/B update on its own and needs no atomic-keep entry — but it
  does need re-applying after each rebuild, which re-running the installer does.
- Bazzite sysext: at IMAGE BUILD time, before mksquashfs. It cannot be done in the merge hook (a
  merged sysext's /usr is read-only squashfs) and it cannot ride in from the RPM either — rpm keeps
  capabilities in its own header and `rpm2cpio | cpio` carries only the payload, so the staged file
  arrives with none. mksquashfs does record security.capability (only security.selinux is
  excluded), so a setcap on the staging tree is what lands in the image. Needs root/CAP_SETFCAP;
  a plain-user CI build warns and ships without it rather than failing a release over a
  performance lever.

Every one of them is best-effort and cannot fail an install: a box without libcap, or a filesystem
that cannot store capabilities, simply runs at default priority exactly as it does today.

Documented in the same PR — the configuration row now says the packages grant it, and
running-as-a-service gets a section explaining what it is, how to check it (`getcap`), and how to
remove it (`setcap -r`, or just `PYROWAVE_QUEUE_PRIORITY=off`), including the two debugging side
effects.

Verified: the Arch scriptlet grants the capability from a fake package root exactly as pacman
would invoke it, and the resulting binary reaches REALTIME end to end on the RTX 5070 Ti; the RPM
spec's %caps line parses under rpmspec in a Fedora 41 container; the NixOS module parses under
nix-instantiate; all five edited shell scripts pass `bash -n`. No Rust file changed in this
commit, so the CI-parity Rust gates from the companion commit still stand.
2026-08-08 15:24:54 +02:00
..

Packaging punktfunk for Fedora / Bazzite

The punktfunk host links system FFmpeg (NVENC on NVIDIA, VAAPI on AMD/Intel, with a GPU-less software-H.264 fallback), PipeWire and Opus. This page covers packaging it for the Fedora Atomic / Bazzite world (rpm-ostree + bootc), where most of those deps are already present; the NVIDIA-specific notes below apply to the NVENC path.

👉 Ubuntu/Debian hosts install via apt from Gitea's package registry — see debian/README.md (apt update && apt upgrade for new builds).

👉 End-to-end Bazzite setup walkthrough (install → udev/group → host.env → service → firewall → verify → troubleshooting): bazzite/README.md. This file is the higher-level packaging rationale.

packaging/
  rpm/punktfunk.spec      # the RPM (builds punktfunk-host from source with cargo)
  bazzite/host.env        # gamescope-default config for a Bazzite appliance
  bazzite/README.md       # step-by-step Bazzite setup guide
  bazzite/*sysext*.sh     # the no-layering path: build/install/publish the systemd-sysext
  bootc/Containerfile     # bake punktfunk into a Bazzite-based atomic image
  copr/                   # COPR build-from-SCM settings

The other packaging targets have their own READMEs: debian/ (apt), arch/ (pacman binary repo + PKGBUILD + SteamOS sysext), flatpak/ (the client), windows/ (host installer + drivers), plus kde/ and linux/ helpers. NixOS / Nix users get a flake (flake.nix at the repo root) with reproducible host + client packages and a services.punktfunk NixOS module — see nix/README.md.

What's needed beyond base Fedora

Dependency Where it comes from
ffmpeg-libs with NVENC RPM Fusion nonfree (ffmpeg, not ffmpeg-free)
NVIDIA driver (libnvidia-encode, libEGL_nvidia) Bazzite -nvidia images ship it; plain Fedora: akmod-nvidia + xorg-x11-drv-nvidia-cuda
gamescope, PipeWire, wireplumber Bazzite ships these; plain Fedora: dnf install gamescope pipewire wireplumber
opus, libei Fedora base / updates

On Bazzite the only genuinely new runtime bits are ffmpeg-libs (RPM Fusion) + opus + libei — the rest of the stack is already there. The default backend is gamescope (packaging/bazzite/host.env), which the host spawns headless per session — no desktop login.

On Bazzite / Fedora Atomic the recommended install is the systemd-sysext image — rpm-ostree layering is a last resort per the Bazzite docs (it slows every OS update and can block upgrades), while a sysext overlays /usr at runtime, survives OS updates, and updates in one command with no reboot. CI wraps the same RPMs below into the image, so content and channels are identical.

curl -fsSLO https://git.unom.io/unom/punktfunk/raw/branch/main/packaging/bazzite/punktfunk-sysext.sh
sudo bash punktfunk-sysext.sh install     # then: sudo punktfunk-sysext update | status | remove

Full walkthrough (incl. the F43→F44 rebase behavior and migration off layering): bazzite/README.md.

Option B — Gitea RPM registry (per-host, rpm-ostree layering)

The host's RPM is published to unom's self-hosted Gitea RPM registry (CI builds it on every push), mirroring the Debian/apt setup. Add one repo file, install, and track updates with rpm-ostree upgrade — no COPR account needed. Full guide: rpm/README.md.

# GPG-signed pkgs + Gitea-signed metadata → gpgcheck=1, repo_gpgcheck=1 (see rpm/README.md)
sudo tee /etc/yum.repos.d/punktfunk.repo >/dev/null <<'REPO'
[gitea-unom-bazzite]
name=punktfunk (unom, Bazzite)
baseurl=https://git.unom.io/api/packages/unom/rpm/bazzite
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://git.unom.io/api/packages/unom/rpm/repository.key
       https://git.unom.io/api/packages/unom/generic/punktfunk-keys/1/RPM-GPG-KEY-punktfunk
REPO
rpm-ostree install punktfunk && systemctl reboot
# updates:  rpm-ostree upgrade && systemctl reboot

Option C — COPR (per-host, rpm-ostree install)

  1. Create a COPR project, enable build-from-SCM pointing at this repo, spec path packaging/rpm/punktfunk.spec (see copr/README.md). Under External Repositories add RPM Fusion nonfree so ffmpeg-devel resolves at build time.
  2. On the Bazzite host:
    # RPM Fusion (for the NVENC ffmpeg) — usually already enabled on Bazzite
    rpm-ostree install \
      https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm \
      https://mirrors.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm
    # enable the COPR + install punktfunk
    sudo wget -O /etc/yum.repos.d/_copr_punktfunk.repo \
      https://copr.fedorainfracloud.org/coprs/enricobuehler/punktfunk/repo/fedora-$(rpm -E %fedora)/
    rpm-ostree install punktfunk
    systemctl reboot
    

Option D — bootc (image-based, atomic)

Layer punktfunk into a Bazzite image once, then rebase any number of hosts onto it — no per-host drift. See bootc/Containerfile:

podman build -t ghcr.io/<you>/bazzite-punktfunk -f packaging/bootc/Containerfile .
podman push  ghcr.io/<you>/bazzite-punktfunk
# on the target:
sudo bootc switch ghcr.io/<you>/bazzite-punktfunk && systemctl reboot

First-run setup (all options)

ujust add-user-to-input-group           # virtual gamepads need /dev/uinput (then re-login).
                                        # On Bazzite use ujust, NOT `usermod -aG input` (atomic OS — it won't stick).
mkdir -p ~/.config/punktfunk
cp /usr/share/punktfunk/host.env.bazzite ~/.config/punktfunk/host.env   # edit (gamescope app, etc.)
systemctl --user enable --now punktfunk-host

# Management web console (pairing + status) — pulled in by default (the host RPM Recommends it;
# `--no-install-recommends` / headless-only boxes can skip it). Enable it and read the login password:
systemctl --user enable --now punktfunk-web
journalctl --user -u punktfunk-web-init | sed -n 's/.*password generated: //p'   # then open https://<host-ip>:47992

Pair a stock Moonlight client (mDNS-discovered), or connect the native punktfunk/1 client — via the web console at https://<host-ip>:47992 or directly.

⚠️ COPR caveat: COPR's mock chroot has no bun, so a COPR build produces only punktfunk + punktfunk-clientnot punktfunk-web. For the console on a COPR/bootc host, install from the Gitea RPM registry (Option B — it carries punktfunk-web; the sysext image includes it too), which is also why bootc/Containerfile installs from there rather than COPR.

Why not Flatpak (for the HOST)?

The host needs unsandboxed access the zero-copy NVENC path, /dev/uinput, the PipeWire graph and the compositor's privileged protocols — a Flatpak sandbox fights all of these. An RPM (or the bootc layer) installs into the host system where those just work.

👉 The client is a different story — it IS shipped as a Flatpak (the only viable Steam Deck install path: SteamOS /usr is read-only and lacks libadwaita/libSDL3). See flatpak/README.md. The client sandbox only needs the GPU render node, Wayland, PipeWire audio, the network and hidraw — all expressible as finish-args.

Building the SRPM/RPM locally (Fedora only)

git archive --format=tar.gz --prefix=punktfunk-0.3.0/ -o ~/rpmbuild/SOURCES/punktfunk-0.3.0.tar.gz HEAD
rpmbuild -ba packaging/rpm/punktfunk.spec     # needs the BuildRequires from the spec
# (0.3.0 = the spec's default %{pf_version}; the prefix and tarball name must match it)

(Not buildable on Debian/Ubuntu — use a Fedora toolbox/container or COPR.)