Convidado do Arch Linux (VirtualBox): não é possível configurar o X

Question

Estou tentando instalar e configurar o Xorg na minha máquina virtual do Arch Linux. Posso iniciar o servidor X com startx , mas quando tento gerar o arquivo de configuração /etc/X11/xorg.conf com o comando Xorg :0 -configure , ele falha. Aqui estão os passos que eu fiz até agora:

1. Instalado o Guest Additions via pacman com os pacotes virtualbox-guest-utils e virtualbox-guest-modules-arch (estou usando o kernel linux padrão, também instalei os cabeçalhos linux-headers ) como descrito aqui ;

2. Criado o arquivo /etc/modules-load.d/virtualbox.conf com as três linhas

   vboxguest
   vboxsf
   vboxvideo
   

   e ativado vboxservice.service ;

3. Instalou os pacotes mesa e xf86-video-vesa ;

4. Instalado xorg-server , xorg-server-utils e xorg-apps ;

5. Instalado openbox e xterm e defina ~/.xintrc da seguinte forma:

   xterm &
   exec openbox
   

6. Rebooted.

o comando startx funciona, mas quando tento gerar o arquivo xorg.conf ele falha. Aqui o arquivo Xorg.0.log :

[  1460.360] 
X.Org X Server 1.18.4
Release Date: 2016-07-19
[  1460.362] X Protocol Version 11, Revision 0
[  1460.365] Build Operating System: Linux 4.5.4-1-ARCH x86_64 
[  1460.367] Current Operating System: Linux ArchLinux 4.7.2-1-ARCH #1 SMP PREEMPT Sat Aug 20 23:02:56 CEST 2016 x86_64
[  1460.368] Kernel command line: BOOT_IMAGE=/vmlinuz-linux root=/dev/mapper/VolGroupArch-root rw quiet
[  1460.369] Build Date: 19 July 2016  05:54:24PM
[  1460.370]  
[  1460.371] Current version of pixman: 0.34.0
[  1460.373]    Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
[  1460.373] Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[  1460.378] (==) Log file: "/home/luigi/.local/share/xorg/Xorg.0.log", Time: Fri Sep  2 20:00:40 2016
[  1460.378] (II) Loader magic: 0x821d40
[  1460.378] (II) Module ABI versions:
[  1460.378]    X.Org ANSI C Emulation: 0.4
[  1460.378]    X.Org Video Driver: 20.0
[  1460.378]    X.Org XInput driver : 22.1
[  1460.378]    X.Org Server Extension : 9.0
[  1460.383] (II) systemd-logind: took control of session /org/freedesktop/login1/session/c1
[  1460.384] (II) xfree86: Adding drm device (/dev/dri/card0)
[  1460.385] (II) systemd-logind: got fd for /dev/dri/card0 226:0 fd 8 paused 0
[  1460.388] (--) PCI:*(0:0:2:0) 80ee:beef:0000:0000 rev 0, Mem @ 0xe0000000/67108864, BIOS @ 0x????????/131072
[  1460.389] List of video drivers:
[  1460.389]    vesa
[  1460.389]    modesetting
[  1460.389] (II) LoadModule: "vesa"
[  1460.389] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[  1460.389] (II) Module vesa: vendor="X.Org Foundation"
[  1460.389]    compiled for 1.18.0, module version = 2.3.4
[  1460.389]    Module class: X.Org Video Driver
[  1460.389]    ABI class: X.Org Video Driver, version 20.0
[  1460.389] (II) LoadModule: "modesetting"
[  1460.389] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[  1460.389] (II) Module modesetting: vendor="X.Org Foundation"
[  1460.389]    compiled for 1.18.4, module version = 1.18.4
[  1460.389]    Module class: X.Org Video Driver
[  1460.389]    ABI class: X.Org Video Driver, version 20.0
[  1460.389] xf86EnableIOPorts: failed to set IOPL for I/O (Operation not permitted)
[  1460.389] (II) VESA: driver for VESA chipsets: vesa
[  1460.389] (II) modeset(G0): using drv /dev/dri/card0
[  1460.389] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[  1460.389] (++) Using config file: "/home/luigi/xorg.conf.new"
[  1460.389] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[  1460.390] (==) ServerLayout "X.org Configured"
[  1460.390] (**) |-->Screen "Screen0" (0)
[  1460.390] (**) |   |-->Monitor "Monitor0"
[  1460.390] (**) |   |-->Device "Card0"
[  1460.390] (**) |-->Input Device "Mouse0"
[  1460.390] (**) |-->Input Device "Keyboard0"
[  1460.390] (==) Automatically adding devices
[  1460.390] (==) Automatically enabling devices
[  1460.390] (==) Automatically adding GPU devices
[  1460.390] (==) Max clients allowed: 256, resource mask: 0x1fffff
[  1460.390] (WW) The directory "/usr/share/fonts/Type1/" does not exist.
[  1460.390]    Entry deleted from font path.
[  1460.390] (WW) 'fonts.dir' not found (or not valid) in "/usr/share/fonts/100dpi/".
[  1460.390]    Entry deleted from font path.
[  1460.390]    (Run 'mkfontdir' on "/usr/share/fonts/100dpi/").
[  1460.390] (WW) 'fonts.dir' not found (or not valid) in "/usr/share/fonts/75dpi/".
[  1460.390]    Entry deleted from font path.
[  1460.390]    (Run 'mkfontdir' on "/usr/share/fonts/75dpi/").
[  1460.390] (WW) The directory "/usr/share/fonts/Type1/" does not exist.
[  1460.390]    Entry deleted from font path.
[  1460.390] (WW) 'fonts.dir' not found (or not valid) in "/usr/share/fonts/100dpi/".
[  1460.390]    Entry deleted from font path.
[  1460.390]    (Run 'mkfontdir' on "/usr/share/fonts/100dpi/").
[  1460.390] (WW) 'fonts.dir' not found (or not valid) in "/usr/share/fonts/75dpi/".
[  1460.390]    Entry deleted from font path.
[  1460.390]    (Run 'mkfontdir' on "/usr/share/fonts/75dpi/").
[  1460.390] (**) FontPath set to:
    /usr/share/fonts/misc/,
    /usr/share/fonts/TTF/,
    /usr/share/fonts/OTF/,
    /usr/share/fonts/misc/,
    /usr/share/fonts/TTF/,
    /usr/share/fonts/OTF/
[  1460.390] (**) ModulePath set to "/usr/lib/xorg/modules"
[  1460.390] (WW) Hotplugging is on, devices using drivers 'kbd', 'mouse' or 'vmmouse' will be disabled.
[  1460.390] (WW) Disabling Mouse0
[  1460.390] (WW) Disabling Keyboard0
[  1460.390] (WW) Falling back to old probe method for vesa
[  1460.390] Number of created screens does not match number of detected devices.
Configuration failed.

Sou iniciante no Arch, sei que estou sentindo falta de algo estúpido. Obrigado em conselhos para você ajudar.