The udisks2 service was enabled to fix the test in (c5ebec7ee4).
However, cagebreak doesn't require udisks2, just polkit (which the
udisks2 module enables and which is why the cagebreak test broke after
the udisks2 module was disabled by default).
I've documented why polkit is required in this PR:
https://github.com/NixOS/nixpkgs/pull/156858
In this case the "dependency" chain is basically cagebreak -> wlroots ->
libseat -> logind (with polkit support) -> polkit.
the default hasn't been changed since 2009
this can improve our test performances
nixos/tests: remove explicit memorySize <1024
1024MiB is now the default
Since the update to wlroots 0.13 (e03dde82a7) the default VGA card
isn't supported anymore and we needed to switch to virtio (qxl didn't
work either). However, as it turned out "-vga virtio" (28b8cff301)
broke the test on AArch64. Luckily there's a third option that works on
all three supported platforms: virtio-gpu-pci
According to [0] "This device lacks VGA compatibility mode but is
otherwise identical to the virtio vga device. UEFI firmware can handle
this, and if your guests has drivers too you can use this instead of
virtio-vga. This will reduce the attack surface (no complex VGA
emulation support) and reduce the memory footprint by 8 MB (no pci
memory bar for VGA compatibility). This device can be placed in a PCI
Express slot."
So in the end this seems like the ideal choice :)
See also [1].
[0]: https://www.kraxel.org/blog/2019/09/display-devices-in-qemu/#virtio-gpu-pci
[1]: https://patches.openembedded.org/patch/164351/
Starting Cagebreak as X11 client doesn't work anymore as wlroots 0.13
started to require the DRI3 extension which isn't supported by LLVMpipe:
machine # [ 13.508284] xsession[938]: 00:00:00.003 [ERROR] [backend/x11/backend.c:433] X11 does not support DRI3 extension
machine # [ 13.666989] show_signal_msg: 62 callbacks suppressed
machine # [ 13.666993] .cagebreak-wrap[938]: segfault at 8 ip 0000000000408574 sp 00007ffef76f2440 error 4 in .cagebreak-wrapped[407000+d000]
machine # [ 13.670483] Code: f4 ff ff 4c 8b 84 24 70 01 00 00 8d 45 01 48 89 c5 49 8b 3c c0 48 85 ff 75 e4 4c 89 c7 e8 84 f4 ff ff 48 8b bc 24 18 01 00 00 <48> 8b 47 08 4c 8d 6f d8 48 8d 68 d8 48 39 df 75 0e eb 36 66 0f 1f
machine # [ 13.518274] xsession[938]: 00:00:00.006 [ERROR] [../cagebreak.c:313] Unable to create the wlroots backend
The test broke after updating Cagebreak in #121652 (bf8679ba94).
XWayland still fails for unknown reasons:
Modifiers specified, but DRI is too old
libEGL warning: DRI2: failed to create dri screen
libEGL warning: NEEDS EXTENSION: falling back to kms_swrast
glamor: No eglstream capable devices found
glamor: 'wl_drm' not supported
Missing Wayland requirements for glamor GBM backend
Missing Wayland requirements for glamor EGLStream backend
Failed to initialize glamor, falling back to sw
00:00:03.534 [ERROR] [xwayland/server.c:252] waitpid for Xwayland fork
failed: No child processes
(EE) failed to write to XWayland fd: Broken pipe
/nix/store/kcm3x8695fgycf31grzl9fy5gggwpram-xterm-367/bin/xterm: Xt
error: Can't open display: :0
The fallback to software rendering is to be expected but it looks like
XWayland is crashing with "failed to write to XWayland fd: Broken pipe".
