SDL3's HIDAPI lg4ff driver advertises an effect-status query it cannot
answer; BeamNG.drive 0.39 native treats the failed query as a dead effect
and the wheel goes limp (12k "Failed to get joystick3 FFB effect status"
lines per session). Steam's environment on this box is exactly this
allowlist, so the hint has to live here, not in /etc/environment.
The narrow hint only demotes the Logitech wheel to the kernel driver;
gamepads keep HIDAPI (rumble, LEDs over Bluetooth).
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SS8M5wk88nJTXxDWz61KKk
Steam's srt-logger runs inside steam-backlog-enforcer.service's cgroup
and mirrors Steam's console into journald on its own — the DEVNULL
stderr the spawn already uses does not reach it, and the env carried
SRT_LOG_TO_JOURNAL=0, which is not the variable it reads. One boot on
2026-09-12 wrote 481k "joystick FFB effect status" lines (99% of the
journal) and evicted two weeks of history from a 300M journal, along
with the evidence for that night's curfew failure.
- desktop_env_args(): SRT_LOGGER_USE_JOURNAL=0, the variable srt-logger
actually honours. Steam keeps its own logs/console-linux.txt.
- Unit: LogFilterPatterns for the two known flood patterns plus a
per-unit rate limit, so a future Steam that ignores the variable still
cannot take the journal with it.
The unit file is deployed and daemon-reloaded; the running service is
not restarted, because Steam is its child and a restart would kill a
live game. The env fix takes effect on the next enforcer start.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015mLnUeoJ3mUwGRTowTUH6d
The enforce service runs as root (no User=) but sets DISPLAY=:0, so any GUI
it starts lands on the desktop session. Two resolvers disagreed about who to
drop privileges to:
library_hider._resolve_desktop_user() read STEAM_ENFORCER_DESKTOP_USER
game_install._get_real_user() read only SUDO_USER or USER
systemd sets neither of the latter, so _get_real_user() returned None under
the service and every `geteuid() == 0 and real_user and ...` guard fell
through to running as root. Steam answered with a zenity modal ("Cannot run
as root user", /usr/lib/steam/steam:261) on screen.
Confirmed from the live process tree: root `bash /usr/lib/steam/steam
-cef-disable-gpu ... steam://install/618510` with a root zenity child. It
never reached the journal, because that text goes to zenity and _run_as_user
sends child output to DEVNULL.
- _desktop_env: add resolve_desktop_user/desktop_uid/desktop_user_cmd. Only
the argv builder is shared, never the spawn call: tests/_no_subprocess.py
patches subprocess per module by name, so a spawn site in an unpatched
module could fire a real `sudo -u kuhy steam`.
- game_install._get_real_user: delegate to the shared resolver. This alone
also fixes the root `steam -silent` in _ensure_steam_running and the
no-op os.chown on new appmanifests.
- _trigger_steam_install / enforcer.send_notification: drop privileges.
send_notification had no DBUS_SESSION_BUS_ADDRESS, so it silently reached
nobody for all six of its callers.
- _run_as_user: fail closed. Running unchanged as root when no desktop user
resolves is what put the modal on screen; refuse and log instead.
Also stop the retry storm behind it. steamapps does not exist (Steam has
never completed sign-in), so is_game_installed() was always False and the
loop re-triggered every allowed game every pass: 1656 attempts in 30
minutes, service RSS 1.5 GB (peak 4.3 GB), a FileNotFoundError traceback
each time. Guard install_game and _reinstall_missing_allowed on
steam_library_ready() -- a missing library means no install can succeed by
any route, so this is a correctness check rather than a tuned retry limit.
The module splits here are forced by the pre-commit 250-line gate, which
blocks any commit touching an over-cap file: game_install, library_hider and
_enforce_loop were already over before this change. They are split by
responsibility (_cdp transport, _steam_launch lifecycle, _steam_process
spawning, _steam_errors, _steam_client, _game_names, game_uninstall,
_enforce_steps, _owned_apps_cache, _echo, _protected_apps). game_install and
library_hider re-export their old public names, so the 15 modules that
import from them are untouched by this commit.
Verified as real root under the unit's environment: argv is now
`sudo -u kuhy env DISPLAY=:0 ... xdg-open steam://install/...` for both the
installer and notify-send; three enforce passes spawn no process and log
once; _run_as_user refuses with no desktop user. After restart: 0 retries,
0 tracebacks, 0 root-owned files under ~/.local/share/Steam, RSS 342 MB.
1311 tests pass. _desktop_env and _steam_state at 100% branch coverage.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016A1EYiv7e7HGhET84oa9M3
The enforcer runs as root under systemd and launches Steam via
`sudo -u <user> env DISPLAY=... XAUTHORITY=... DBUS_SESSION_BUS_ADDRESS=...`.
sudo uses env_reset, so that list is the child's entire environment - an
allowlist where every omission fails silently.
XDG_RUNTIME_DIR was missing. Without it Wine cannot reach
$XDG_RUNTIME_DIR/pulse/native, falls back from winepulse.drv to
winealsa.drv, and hands FMOD raw ALSA devices instead of the session sink.
Kingdom Come: Deliverance II died in its Bink startup video as a result.
Across 18 sessions the split was total: 9/9 runs logging "PulseAudio
Output" exited cleanly, 9/9 logging "HDA NVidia" crashed on the same line.
It presented as a corrupt install - the apparent cure was a 92GB reinstall -
but verify-integrity always passed. What actually fixed it was the Steam
restart the reinstall incidentally performed.
Extract the duplicated env construction into _desktop_env.desktop_env_args
and derive XDG_RUNTIME_DIR from the target uid, never from the ambient
environment: root's own value would point the child at /run/user/0.
PULSE_SERVER is deliberately not exported. pressure-vessel reads
XDG_RUNTIME_DIR to bind-mount the pulse socket into the Steam Linux Runtime
container, whereas a hardcoded unix:/run/user/<uid>/pulse/native names a
host path that need not resolve inside it.
Also gate the launch on the session existing. The enforcer is ordered only
After=network-online, while /run/user/<uid> is created by
user-runtime-dir@<uid>.service; on a measured boot the enforcer started 54ms
before that unit and won only by doing other work first. Launching in that
window would name a runtime dir that is not there and reintroduce the same
silent winealsa fallback for the whole session, so defer instead - the
enforce loop already retries every 3s, and DesktopSessionNotReadyError
subclasses SteamUnavailableError so existing callers degrade as before.
An ordering dependency would not be reliable here, since logind may start
user-runtime-dir outside the boot transaction.
Verified on the failing path rather than a dev shell: after restarting the
enforcer, the Steam it launched carried XDG_RUNTIME_DIR=/run/user/1000 and
KCD2 ran 15 minutes on "PulseAudio Output" with no crash artifacts.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
