Source: mutter
Version: 48.4-2
Severity: important
Tags: ftbfs unreproducible
User: [email protected]
Usertags: flaky

In one autopkgtest on ppc64el, https://ci.debian.net/packages/m/mutter/testing/ppc64el/62167381/ we can
see this failure:

609s # Running test: mutter-16/xwayland.test
611s # Executing: mutter-16/xwayland.test
611s # FAIL: mutter-16/xwayland.test (Child process exited with code 250) >611s not ok - mutter-16/xwayland.test

...

652s # SUMMARY: total=34; passed=31; skipped=0; failed=3; user=54.7s; system=14.5s; maxrss=1146276

...

652s # FAIL: mutter-16/xwayland.test (Child process exited with code 250)

For further details of that failure we have to look in the $AUTOPKGTEST_ARTIFACTS (artifacts.tar.gz on ci.debian.net) and read artifacts/mutter-16_xwayland.test.txt, quoted in full here:

Setup HOME as /tmp/mutter-testroot-ksve67fk/home
Setup TMPDIR as /tmp/mutter-testroot-ksve67fk/tmpdir
Setup XDG_CACHE_HOME as /tmp/mutter-testroot-ksve67fk/xdg_cache_home
Setup XDG_CONFIG_HOME as /tmp/mutter-testroot-ksve67fk/xdg_config_home
Setup XDG_DATA_HOME as /tmp/mutter-testroot-ksve67fk/xdg_data_home
Setup XDG_RUNTIME_DIR as /tmp/mutter-testroot-ksve67fk/xdg_runtime_dir >Starting D-Bus daemons (session & system)...
Binding /tmp/mutter-testroot-ksve67fk/xdg_runtime_dir/pipewire-0 for socket activation
Binding /tmp/mutter-testroot-ksve67fk/xdg_runtime_dir/pipewire-0-manager for socket activation
Launching required services...
Starting mocked services...
ERROR:dbus.proxies:Introspect error on :1.1:/org/freedesktop/login1/session/dummy: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.UnknownObject: Unknown object '/org/freedesktop/login1/session/dummy'.
Running test case...
Process ['/usr/libexec/installed-tests/mutter-16/mutter-xwayland'] started with pid 7648
TAP version 14
# random seed: R02Sf7315ed43b1f8d8533e16a903f372db9
# GLib-GIO-DEBUG: _g_io_module_get_default: Found default implementation memory (GMemorySettingsBackend) for ‘gsettings-backend’
# GLib-DEBUG: setenv()/putenv() are not thread-safe and should not be used after threads are created
# libmutter-MESSAGE: Running Mutter Test (using mutter 48.4) as a Wayland display server
# libmutter-MESSAGE: Created surfaceless renderer without GPU
# GLib-GIO-DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ‘gio-vfs’
# libmutter-DEBUG: WL: Unable to initialize wl_eglstream_controller.
# libmutter-MESSAGE: Using public X11 display :512, (using :513 for managed services)
# libmutter-MESSAGE: Using Wayland display name 'mutter-test-display'
1..4
# Start of backends tests
# Start of xwayland tests
# Start of compositor tests
# libmutter-INFO: Acquired name org.gnome.Mutter.InputMapping
# libmutter-DEBUG: Acquired name org.freedesktop.a11y.Manager
# libmutter-INFO: Acquired name org.gnome.Mutter.ServiceChannel
Xwayland glamor: GBM Wayland interfaces not available
Failed to initialize glamor, falling back to sw
NO X11 Compositor is available for display :512:0
** >mutter-xwayland-test:ERROR:../src/tests/xwayland-tests.c:257:compositor_check_proc_async: assertion failed (error == NULL): Child process exited with code 1 (g-spawn-exit-error-quark, 1)
not ok /backends/xwayland/compositor/selection - mutter-xwayland-test:ERROR:../src/tests/xwayland-tests.c:257:compositor_check_proc_async: assertion failed (error == NULL): Child process exited with code 1 (g-spawn-exit-error-quark, 1)
Bail out!
(EE) failed to read Wayland events: Connection reset by peer
Closing PipeWire socket...
Terminating services...

(mutter-x11-frames:7694): Gtk-WARNING **: 09:16:49.718: Failed to open display

This could perhaps be a race condition: maybe the test client is racing
with startup of the Wayland compositor, such that if the compositor wins
the race (as it usually does), everything will work as expected, but if
the test client wins the race, the test will fail? But that's only a
theory.

I've only observed this once on ci.debian.net, but in principle it
ought to affect autopkgtest and build-time tests equally, hence the
ftbfs tag.

smcv

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)