ubuntu - xorg - Error de X.Org en Kubuntu en MacPro

Estoy intentando instalar Ubuntu 17.04 (Zesty) en mi Mac Pro (Trashcan).

Sin nomodeset en los parámetros de arranque, X.Org finaliza al iniciarse. La pantalla alterna entre un tty2 en funcionamiento y un tty dañado aproximadamente cada 3 segundos. La cola de /var/log/Xorg.0.log es…

[   161.049] (II) RADEON(G0): [DRI2] Setup complete
[   161.049] (II) RADEON(G0): [DRI2]   DRI driver: radeonsi
[   161.049] (II) RADEON(G0): [DRI2]   VDPAU driver: radeonsi
[   161.049] (EE) RADEON(G0): failed to initialise surface manager
[   161.049] (EE) RADEON(G0): radeon_setup_kernel_mem failed
[   161.049] (EE) Fatal server error:
[   161.049] (EE) AddScreen/ScreenInit failed for gpu driver 0 -1
[   161.049] (EE) 
[   161.049] (EE) 
Please consult the The X.Org Foundation support 
     at http://wiki.x.org
for help. 
[   161.049] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[   161.049] (EE) 
[   161.068] (EE) Server terminated with error (1). Closing log file.

…pero, más arriba están las líneas…

[   160.104] (II) Applying OutputClass "Radeon" to /dev/dri/card0
[   160.104]    loading driver: radeon
[   160.104] (II) Applying OutputClass "AMDgpu" to /dev/dri/card1
[   160.104]    loading driver: amdgpu

Si hay 2 tarjetas de vídeo idénticas, ¿no debería usarse el mismo controlador para ambas?

Al iniciar con nomodeset en los parámetros de inicio, puedo ejecutar x.org y permitirme abrir una ventana de terminal. Al hacerlo y ejecutar lspci -k | grep -EA3 'VGA|Pantalla' obtengo

02:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Curacao XT / Trinidad XT [Radeon R7 370 / R9 270X/370X]
    Subsystem: Apple Inc. Curacao XT / Trinidad XT [Radeon R7 370 / R9 270X/370X]
    Kernel modules: radeon, amdgpu
02:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]
--
06:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Curacao XT / Trinidad XT [Radeon R7 370 / R9 270X/370X]
    Subsystem: Apple Inc. Curacao XT / Trinidad XT [Radeon R7 370 / R9 270X/370X]
    Kernel modules: radeon, amdgpu
06:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]

Además, al mirar /var/log/syslog, la palabra 'segfault' aparece 32 veces, 'error' 92 veces, 'fail' 195…. ¿Esto es normal?

Detalles a continuación…

Kubuntu 17.04 de 64 bits para escritorio instalado en una unidad USB3 desde una memoria USB de arranque.

Mac Pro (finales de 2013), también conocido como MacPro6,1

2 tarjetas gráficas de video AMD FirePro D300 (GPU basada en Pitcairn) a las que se hace referencia como “en esencia la W7000 pero con la mitad de VRAM” https://architosh.com/2013/10/the-mac-pro -entonces-qué-es-un-d300-d500-y-d700-de todos modos-tenemos-respuestas/

Xorg.O.log completo

[   160.090] 
X.Org X Server 1.19.3
Release Date: 2017-03-15
[   160.090] X Protocol Version 11, Revision 0
[   160.090] Build Operating System: Linux 4.4.0-70-generic x86_64 Ubuntu
[   160.091] Current Operating System: Linux hans-MacPro 4.10.0-32-generic #36-Ubuntu SMP Tue Aug 8 12:10:06 UTC 2017 x86_64
[   160.091] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.10.0-32-generic.efi.signed root=/dev/sdb2
[   160.091] Build Date: 28 March 2017  06:16:52AM
[   160.091] xorg-server 2:1.19.3-1ubuntu1 (For technical support please see http://www.ubuntu.com/support) 
[   160.091] Current version of pixman: 0.34.0
[   160.091]    Before reporting problems, check http://wiki.x.org
    to make sure that you have the latest version.
[   160.091] Markers: (--) probed, (**) from config file, (==) default setting,
    (++) from command line, (!!) notice, (II) informational,
    (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[   160.091] (==) Log file: "/var/log/Xorg.0.log", Time: Thu Aug 17 16:59:42 2017
[   160.091] (==) Using system config directory "/usr/share/X11/xorg.conf.d"
[   160.091] (==) No Layout section.  Using the first Screen section.
[   160.091] (==) No screen section available. Using defaults.
[   160.091] (**) |-->Screen "Default Screen Section" (0)
[   160.091] (**) |   |-->Monitor "<default monitor>"
[   160.091] (==) No monitor specified for screen "Default Screen Section".
    Using a default monitor configuration.
[   160.091] (==) Automatically adding devices
[   160.091] (==) Automatically enabling devices
[   160.091] (==) Automatically adding GPU devices
[   160.092] (==) Automatically binding GPU devices
[   160.092] (==) Max clients allowed: 256, resource mask: 0x1fffff
[   160.092] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist.
[   160.092]    Entry deleted from font path.
[   160.092] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist.
[   160.092]    Entry deleted from font path.
[   160.092] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist.
[   160.092]    Entry deleted from font path.
[   160.092] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist.
[   160.092]    Entry deleted from font path.
[   160.092] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist.
[   160.092]    Entry deleted from font path.
[   160.092] (==) FontPath set to:
    /usr/share/fonts/X11/misc,
    /usr/share/fonts/X11/Type1,
    built-ins
[   160.092] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib/xorg/modules"
[   160.092] (II) The server relies on udev to provide the list of input devices.
    If no devices become available, reconfigure udev or disable AutoAddDevices.
[   160.092] (II) Loader magic: 0x56343af47020
[   160.092] (II) Module ABI versions:
[   160.092]    X.Org ANSI C Emulation: 0.4
[   160.092]    X.Org Video Driver: 23.0
[   160.092]    X.Org XInput driver : 24.1
[   160.092]    X.Org Server Extension : 10.0
[   160.093] (++) using VT number 7

[   160.093] (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
[   160.094] (II) xfree86: Adding drm device (/dev/dri/card1)
[   160.096] (II) xfree86: Adding drm device (/dev/dri/card0)
[   160.102] (--) PCI: (0:2:0:0) 1002:6810:106b:012b rev 0, Mem @ 0x80000000/268435456, 0xa0700000/262144, I/O @ 0x00003000/256, BIOS @ 0x????????/131072
[   160.102] (--) PCI:*(0:6:0:0) 1002:6810:106b:012a rev 0, Mem @ 0x90000000/268435456, 0xa0600000/262144, I/O @ 0x00002000/256, BIOS @ 0x????????/131072
[   160.102] (II) LoadModule: "glx"
[   160.103] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so
[   160.104] (II) Module glx: vendor="X.Org Foundation"
[   160.104]    compiled for 1.19.3, module version = 1.0.0
[   160.104]    ABI class: X.Org Server Extension, version 10.0
[   160.104] (II) Applying OutputClass "Radeon" to /dev/dri/card0
[   160.104]    loading driver: radeon
[   160.104] (II) Applying OutputClass "AMDgpu" to /dev/dri/card1
[   160.104]    loading driver: amdgpu
[   160.104] (==) Matched radeon as autoconfigured driver 0
[   160.104] (==) Matched ati as autoconfigured driver 1
[   160.104] (==) Matched amdgpu as autoconfigured driver 2
[   160.104] (==) Matched ati as autoconfigured driver 3
[   160.104] (==) Matched ati as autoconfigured driver 4
[   160.104] (==) Matched modesetting as autoconfigured driver 5
[   160.104] (==) Matched fbdev as autoconfigured driver 6
[   160.104] (==) Matched vesa as autoconfigured driver 7
[   160.104] (==) Assigned the driver to the xf86ConfigLayout
[   160.104] (II) LoadModule: "radeon"
[   160.104] (II) Loading /usr/lib/xorg/modules/drivers/radeon_drv.so
[   160.104] (II) Module radeon: vendor="X.Org Foundation"
[   160.104]    compiled for 1.19.3, module version = 7.9.0
[   160.104]    Module class: X.Org Video Driver
[   160.104]    ABI class: X.Org Video Driver, version 23.0
[   160.105] (II) LoadModule: "ati"
[   160.105] (II) Loading /usr/lib/xorg/modules/drivers/ati_drv.so
[   160.105] (II) Module ati: vendor="X.Org Foundation"
[   160.105]    compiled for 1.19.3, module version = 7.9.0
[   160.105]    Module class: X.Org Video Driver
[   160.105]    ABI class: X.Org Video Driver, version 23.0
[   160.164] (II) LoadModule: "amdgpu"
[   160.164] (II) Loading /usr/lib/xorg/modules/drivers/amdgpu_drv.so
[   160.165] (II) Module amdgpu: vendor="X.Org Foundation"
[   160.165]    compiled for 1.19.3, module version = 1.3.0
[   160.165]    Module class: X.Org Video Driver
[   160.165]    ABI class: X.Org Video Driver, version 23.0
[   160.165] (II) LoadModule: "modesetting"
[   160.165] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
[   160.165] (II) Module modesetting: vendor="X.Org Foundation"
[   160.165]    compiled for 1.19.3, module version = 1.19.3
[   160.165]    Module class: X.Org Video Driver
[   160.165]    ABI class: X.Org Video Driver, version 23.0
[   160.165] (II) LoadModule: "fbdev"
[   160.166] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so
[   160.166] (II) Module fbdev: vendor="X.Org Foundation"
[   160.166]    compiled for 1.19.3, module version = 0.4.4
[   160.166]    Module class: X.Org Video Driver
[   160.166]    ABI class: X.Org Video Driver, version 23.0
[   160.166] (II) LoadModule: "vesa"
[   160.166] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so
[   160.166] (II) Module vesa: vendor="X.Org Foundation"
[   160.166]    compiled for 1.19.3, module version = 2.3.4
[   160.166]    Module class: X.Org Video Driver
[   160.166]    ABI class: X.Org Video Driver, version 23.0
[   160.166] (II) RADEON: Driver for ATI/AMD Radeon chipsets:
    ATI Radeon Mobility X600 (M24), ATI FireMV 2400,
...skipping for space...
AMD Radeon HD 6800 Series, AMD Radeon HD 6700 Series, TURKS, CAICOS,
    ARUBA, TAHITI, PITCAIRN, VERDE, OLAND, HAINAN, BONAIRE, KABINI,
    MULLINS, KAVERI, HAWAII
[   160.169] (II) AMDGPU: Driver for AMD Radeon:
    All GPUs supported by the amdgpu kernel driver
[   160.169] (II) modesetting: Driver for Modesetting Kernel Drivers: kms
[   160.169] (II) FBDEV: driver for framebuffer: fbdev
[   160.169] (II) VESA: driver for VESA chipsets: vesa
[   160.180] (II) [KMS] Kernel modesetting enabled.
[   160.180] (II) [KMS] Kernel modesetting enabled.
[   160.180] (WW) Falling back to old probe method for modesetting
[   160.180] (WW) Falling back to old probe method for fbdev
[   160.180] (II) Loading sub module "fbdevhw"
[   160.180] (II) LoadModule: "fbdevhw"
[   160.180] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so
[   160.181] (II) Module fbdevhw: vendor="X.Org Foundation"
[   160.181]    compiled for 1.19.3, module version = 0.0.2
[   160.181]    ABI class: X.Org Video Driver, version 23.0
[   160.181] (WW) Falling back to old probe method for vesa
[   160.181] (II) RADEON(0): Creating default Display subsection in Screen section
    "Default Screen Section" for depth/fbbpp 24/32
[   160.181] (==) RADEON(0): Depth 24, (--) framebuffer bpp 32
[   160.181] (II) RADEON(0): Pixel depth = 24 bits stored in 4 bytes (32 bpp pixmaps)
[   160.181] (==) RADEON(0): Default visual is TrueColor
[   160.181] (==) RADEON(0): RGB weight 888
[   160.181] (II) RADEON(0): Using 8 bits per RGB (8 bit DAC)
[   160.181] (--) RADEON(0): Chipset: "PITCAIRN" (ChipID = 0x6810)
[   160.181] (II) Loading sub module "fb"
[   160.181] (II) LoadModule: "fb"
[   160.181] (II) Loading /usr/lib/xorg/modules/libfb.so
[   160.182] (II) Module fb: vendor="X.Org Foundation"
[   160.182]    compiled for 1.19.3, module version = 1.0.0
[   160.182]    ABI class: X.Org ANSI C Emulation, version 0.4
[   160.182] (II) Loading sub module "dri2"
[   160.182] (II) LoadModule: "dri2"
[   160.182] (II) Module "dri2" already built-in
[   160.182] (II) Loading sub module "glamoregl"
[   160.182] (II) LoadModule: "glamoregl"
[   160.182] (II) Loading /usr/lib/xorg/modules/libglamoregl.so
[   160.189] (II) Module glamoregl: vendor="X.Org Foundation"
[   160.189]    compiled for 1.19.3, module version = 1.0.0
[   160.189]    ABI class: X.Org ANSI C Emulation, version 0.4
[   160.189] (II) glamor: OpenGL accelerated X.org driver based.
[   160.231] (II) glamor: EGL version 1.4 (DRI2):
[   160.234] (II) RADEON(0): glamor detected, initialising EGL layer.
[   160.234] (II) RADEON(0): KMS Color Tiling: enabled
[   160.234] (II) RADEON(0): KMS Color Tiling 2D: enabled
[   160.234] (==) RADEON(0): TearFree property default: auto
[   160.234] (II) RADEON(0): KMS Pageflipping: enabled
[   160.265] (II) RADEON(0): Output DisplayPort-0 has no monitor section
[   160.297] (II) RADEON(0): Output DisplayPort-1 has no monitor section
[   160.348] (II) RADEON(0): Output DisplayPort-2 has no monitor section
[   160.381] (II) RADEON(0): Output DisplayPort-3 has no monitor section
[   160.413] (II) RADEON(0): Output DisplayPort-4 has no monitor section
[   160.445] (II) RADEON(0): Output DisplayPort-5 has no monitor section
[   160.477] (II) RADEON(0): EDID for output DisplayPort-0
[   160.509] (II) RADEON(0): EDID for output DisplayPort-1
[   160.560] (II) RADEON(0): EDID for output DisplayPort-2
[   160.560] (II) RADEON(0): Manufacturer: ACR  Model: 2c5  Serial#: 855642923
[   160.560] (II) RADEON(0): Year: 2013  Week: 30
[   160.560] (II) RADEON(0): EDID Version: 1.3
[   160.560] (II) RADEON(0): Digital Display Input
[   160.560] (II) RADEON(0): Max Image Size [cm]: horiz.: 52  vert.: 32
[   160.560] (II) RADEON(0): Gamma: 2.20
[   160.560] (II) RADEON(0): DPMS capabilities: Off
[   160.560] (II) RADEON(0): Supported color encodings: RGB 4:4:4 YCrCb 4:4:4 
[   160.560] (II) RADEON(0): First detailed timing is preferred mode
[   160.560] (II) RADEON(0): redX: 0.647 redY: 0.331   greenX: 0.314 greenY: 0.621
[   160.560] (II) RADEON(0): blueX: 0.151 blueY: 0.070   whiteX: 0.313 whiteY: 0.329
[   160.560] (II) RADEON(0): Supported established timings:
[   160.560] (II) RADEON(0): 720x400@70Hz
[   160.560] (II) RADEON(0): 640x480@60Hz
[   160.560] (II) RADEON(0): 640x480@67Hz
[   160.560] (II) RADEON(0): 640x480@72Hz
[   160.560] (II) RADEON(0): 640x480@75Hz
[   160.560] (II) RADEON(0): 800x600@56Hz
[   160.560] (II) RADEON(0): 800x600@60Hz
[   160.560] (II) RADEON(0): 800x600@72Hz
[   160.560] (II) RADEON(0): 800x600@75Hz
[   160.560] (II) RADEON(0): 832x624@75Hz
[   160.560] (II) RADEON(0): 1024x768@60Hz
[   160.560] (II) RADEON(0): 1024x768@70Hz
[   160.560] (II) RADEON(0): 1024x768@75Hz
[   160.560] (II) RADEON(0): 1280x1024@75Hz
[   160.560] (II) RADEON(0): 1152x864@75Hz
[   160.560] (II) RADEON(0): Manufacturer's mask: 0
[   160.560] (II) RADEON(0): Supported standard timings:
[   160.560] (II) RADEON(0): #0: hsize: 1152  vsize 864  refresh: 75  vid: 20337
[   160.560] (II) RADEON(0): #1: hsize: 1280  vsize 1024  refresh: 60  vid: 32897
[   160.560] (II) RADEON(0): #2: hsize: 1280  vsize 960  refresh: 60  vid: 16513
[   160.560] (II) RADEON(0): #3: hsize: 1280  vsize 720  refresh: 60  vid: 49281
[   160.560] (II) RADEON(0): #4: hsize: 1280  vsize 800  refresh: 60  vid: 129
[   160.560] (II) RADEON(0): #5: hsize: 1680  vsize 1050  refresh: 60  vid: 179
[   160.560] (II) RADEON(0): Supported detailed timing:
[   160.560] (II) RADEON(0): clock: 154.0 MHz   Image Size:  518 x 324 mm
[   160.560] (II) RADEON(0): h_active: 1920  h_sync: 1968  h_sync_end 2000 h_blank_end 2080 h_border: 0
[   160.560] (II) RADEON(0): v_active: 1200  v_sync: 1203  v_sync_end 1209 v_blanking: 1235 v_border: 0
[   160.560] (II) RADEON(0): Ranges: V min: 56 V max: 75 Hz, H min: 30 H max: 83 kHz, PixClock max 185 MHz
[   160.560] (II) RADEON(0): Serial No: LV6AA0014239
[   160.560] (II) RADEON(0): Monitor name: Acer B243PWL
[   160.560] (II) RADEON(0): EDID (in hex):
[   160.560] (II) RADEON(0):    00ffffffffffff000472c5022b130033
[   160.560] (II) RADEON(0):    1e170103803420782af8c5a554509f26
[   160.560] (II) RADEON(0):    125054bfef80714f8180814081c08100
[   160.560] (II) RADEON(0):    b30001010101283c80a070b023403020
[   160.560] (II) RADEON(0):    360006442100001a000000fd00384b1e
[   160.560] (II) RADEON(0):    5312000a202020202020000000ff004c
[   160.560] (II) RADEON(0):    56364141303031343233390a000000fc
[   160.560] (II) RADEON(0):    0041636572204232343350574c0a00eb
[   160.560] (II) RADEON(0): Printing probed modes for output DisplayPort-2
[   160.560] (II) RADEON(0): Modeline "1920x1200"x60.0  154.00  1920 1968 2000 2080  1200 1203 1209 1235 +hsync -vsync (74.0 kHz eP)
[   160.560] (II) RADEON(0): Modeline "1680x1050"x59.9  119.00  1680 1728 1760 1840  1050 1053 1059 1080 +hsync -vsync (64.7 kHz e)
[   160.560] (II) RADEON(0): Modeline "1280x1024"x75.0  135.00  1280 1296 1440 1688  1024 1025 1028 1066 +hsync +vsync (80.0 kHz e)
[   160.560] (II) RADEON(0): Modeline "1280x1024"x60.0  108.00  1280 1328 1440 1688  1024 1025 1028 1066 +hsync +vsync (64.0 kHz e)
[   160.560] (II) RADEON(0): Modeline "1280x960"x60.0  108.00  1280 1376 1488 1800  960 961 964 1000 +hsync +vsync (60.0 kHz e)
[   160.560] (II) RADEON(0): Modeline "1280x800"x59.9   71.00  1280 1328 1360 1440  800 803 809 823 +hsync -vsync (49.3 kHz e)
[   160.560] (II) RADEON(0): Modeline "1152x864"x75.0  108.00  1152 1216 1344 1600  864 865 868 900 +hsync +vsync (67.5 kHz e)
[   160.560] (II) RADEON(0): Modeline "1280x720"x60.0   74.25  1280 1390 1430 1650  720 725 730 750 +hsync +vsync (45.0 kHz e)
[   160.560] (II) RADEON(0): Modeline "1024x768"x75.0   78.75  1024 1040 1136 1312  768 769 772 800 +hsync +vsync (60.0 kHz e)
[   160.560] (II) RADEON(0): Modeline "1024x768"x70.1   75.00  1024 1048 1184 1328  768 771 777 806 -hsync -vsync (56.5 kHz e)
[   160.560] (II) RADEON(0): Modeline "1024x768"x60.0   65.00  1024 1048 1184 1344  768 771 777 806 -hsync -vsync (48.4 kHz e)
[   160.560] (II) RADEON(0): Modeline "832x624"x74.6   57.28  832 864 928 1152  624 625 628 667 -hsync -vsync (49.7 kHz e)
[   160.560] (II) RADEON(0): Modeline "800x600"x72.2   50.00  800 856 976 1040  600 637 643 666 +hsync +vsync (48.1 kHz e)
[   160.560] (II) RADEON(0): Modeline "800x600"x75.0   49.50  800 816 896 1056  600 601 604 625 +hsync +vsync (46.9 kHz e)
[   160.560] (II) RADEON(0): Modeline "800x600"x60.3   40.00  800 840 968 1056  600 601 605 628 +hsync +vsync (37.9 kHz e)
[   160.560] (II) RADEON(0): Modeline "800x600"x56.2   36.00  800 824 896 1024  600 601 603 625 +hsync +vsync (35.2 kHz e)
[   160.561] (II) RADEON(0): Modeline "640x480"x75.0   31.50  640 656 720 840  480 481 484 500 -hsync -vsync (37.5 kHz e)
[   160.561] (II) RADEON(0): Modeline "640x480"x72.8   31.50  640 664 704 832  480 489 492 520 -hsync -vsync (37.9 kHz e)
[   160.561] (II) RADEON(0): Modeline "640x480"x66.7   30.24  640 704 768 864  480 483 486 525 -hsync -vsync (35.0 kHz e)
[   160.561] (II) RADEON(0): Modeline "640x480"x59.9   25.18  640 656 752 800  480 490 492 525 -hsync -vsync (31.5 kHz e)
[   160.561] (II) RADEON(0): Modeline "720x400"x70.1   28.32  720 738 846 900  400 412 414 449 -hsync +vsync (31.5 kHz e)
[   160.593] (II) RADEON(0): EDID for output DisplayPort-3
[   160.625] (II) RADEON(0): EDID for output DisplayPort-4
[   160.657] (II) RADEON(0): EDID for output DisplayPort-5
[   160.657] (II) RADEON(0): Output DisplayPort-0 disconnected
[   160.657] (II) RADEON(0): Output DisplayPort-1 disconnected
[   160.657] (II) RADEON(0): Output DisplayPort-2 connected
[   160.657] (II) RADEON(0): Output DisplayPort-3 disconnected
[   160.657] (II) RADEON(0): Output DisplayPort-4 disconnected
[   160.657] (II) RADEON(0): Output DisplayPort-5 disconnected
[   160.657] (II) RADEON(0): Using exact sizes for initial modes
[   160.657] (II) RADEON(0): Output DisplayPort-2 using initial mode 1920x1200 +0+0
[   160.657] (II) RADEON(0): mem size init: gart size :7fbcc000 vram size: s:80000000 visible:f15e000
[   160.657] (==) RADEON(0): DPI set to (96, 96)
[   160.657] (==) RADEON(0): Using gamma correction (1.0, 1.0, 1.0)
[   160.657] (II) Loading sub module "ramdac"
[   160.657] (II) LoadModule: "ramdac"
[   160.657] (II) Module "ramdac" already built-in
[   160.657] (==) RADEON(G0): Depth 24, (--) framebuffer bpp 32
[   160.657] (II) RADEON(G0): Pixel depth = 24 bits stored in 4 bytes (32 bpp pixmaps)
[   160.657] (==) RADEON(G0): Default visual is TrueColor
[   160.657] (==) RADEON(G0): RGB weight 888
[   160.657] (II) RADEON(G0): Using 8 bits per RGB (8 bit DAC)
[   160.657] (--) RADEON(G0): Chipset: "PITCAIRN" (ChipID = 0x6810)
[   160.657] (II) Loading sub module "fb"
[   160.657] (II) LoadModule: "fb"
[   160.658] (II) Loading /usr/lib/xorg/modules/libfb.so
[   160.658] (II) Module fb: vendor="X.Org Foundation"
[   160.658]    compiled for 1.19.3, module version = 1.0.0
[   160.658]    ABI class: X.Org ANSI C Emulation, version 0.4
[   160.658] (II) RADEON(G0): Kernel too old missing accel information, assuming accel is working
[   160.658] (II) Loading sub module "dri2"
[   160.658] (II) LoadModule: "dri2"
[   160.658] (II) Module "dri2" already built-in
[   160.658] (II) Loading sub module "glamoregl"
[   160.658] (II) LoadModule: "glamoregl"
[   160.658] (II) Loading /usr/lib/xorg/modules/libglamoregl.so
[   160.658] (II) Module glamoregl: vendor="X.Org Foundation"
[   160.658]    compiled for 1.19.3, module version = 1.0.0
[   160.658]    ABI class: X.Org ANSI C Emulation, version 0.4
[   160.658] (II) glamor: OpenGL accelerated X.org driver based.
[   160.664] (II) glamor: EGL version 1.4 (DRI2):
[   160.666] (II) RADEON(G0): glamor detected, initialising EGL layer.
[   160.666] (II) RADEON(G0): KMS Color Tiling: disabled
[   160.666] (II) RADEON(G0): KMS Color Tiling 2D: enabled
[   160.666] (==) RADEON(G0): TearFree property default: auto
[   160.696] (II) RADEON(G0): Output DisplayPort-1-6 has no monitor section
[   160.728] (II) RADEON(G0): Output DisplayPort-1-7 has no monitor section
[   160.760] (II) RADEON(G0): Output DisplayPort-1-8 has no monitor section
[   160.793] (II) RADEON(G0): Output DisplayPort-1-9 has no monitor section
[   160.824] (II) RADEON(G0): Output DisplayPort-1-10 has no monitor section
[   160.857] (II) RADEON(G0): Output DisplayPort-1-11 has no monitor section
[   160.888] (II) RADEON(G0): EDID for output DisplayPort-1-6
[   160.920] (II) RADEON(G0): EDID for output DisplayPort-1-7
[   160.953] (II) RADEON(G0): EDID for output DisplayPort-1-8
[   160.985] (II) RADEON(G0): EDID for output DisplayPort-1-9
[   161.017] (II) RADEON(G0): EDID for output DisplayPort-1-10
[   161.048] (II) RADEON(G0): EDID for output DisplayPort-1-11
[   161.049] (==) RADEON(G0): DPI set to (96, 96)
[   161.049] (==) RADEON(G0): Using gamma correction (1.0, 1.0, 1.0)
[   161.049] (II) Loading sub module "ramdac"
[   161.049] (II) LoadModule: "ramdac"
[   161.049] (II) Module "ramdac" already built-in
[   161.049] (II) UnloadModule: "amdgpu"
[   161.049] (II) Unloading amdgpu
[   161.049] (II) UnloadModule: "modesetting"
[   161.049] (II) Unloading modesetting
[   161.049] (II) UnloadModule: "fbdev"
[   161.049] (II) Unloading fbdev
[   161.049] (II) UnloadSubModule: "fbdevhw"
[   161.049] (II) Unloading fbdevhw
[   161.049] (II) UnloadModule: "vesa"
[   161.049] (II) Unloading vesa
[   161.049] (--) Depth 24 pixmap format is 32 bpp
[   161.049] (II) RADEON(G0): [DRI2] Setup complete
[   161.049] (II) RADEON(G0): [DRI2]   DRI driver: radeonsi
[   161.049] (II) RADEON(G0): [DRI2]   VDPAU driver: radeonsi
[   161.049] (EE) RADEON(G0): failed to initialise surface manager
[   161.049] (EE) RADEON(G0): radeon_setup_kernel_mem failed
[   161.049] (EE) 
Fatal server error:
[   161.049] (EE) AddScreen/ScreenInit failed for gpu driver 0 -1
[   161.049] (EE) 
[   161.049] (EE) 
Please consult the The X.Org Foundation support 
     at http://wiki.x.org
 for help. 
[   161.049] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[   161.049] (EE) 
[   161.068] (EE) Server terminated with error (1). Closing log file.

...7/9/2017 Este mismo problema ocurre en 16.04.3 LTS, pero luego se vuelve extraño. La pantalla cambia a blanco y regresa 3 veces más rápido y luego está bien durante 1,5 segundos. El teclado sólo responde a las teclas mágicas cuando NO está en blanco. La tecla mágica U detiene el parpadeo y estabiliza el sistema cuando está en tty. Lo extraño es que si intento reiniciar repetidamente el sistema, se iniciará¿Un buen sistema que funciona una vez cada 4 o 6 intentos? ¿Cómo se depura eso?

• Edite su preguntaestion y agrega salida de lspci -k | grep -EA3 'VGA|Pantalla' comando de terminal. Piloto6 18 de agosto de 2017 a las 19:39
• ¿Arrancar con nomodeset y luego obtener el resultado? El sistema no funciona sin él. La terminal simplemente salta de un lado a otro.- FyFAIR 18 de agosto de 2017 a las 23:45
• @H.P.Z. Si como siempre. No tiene relación con los resultados del comando solicitado –usuario692175 19 de agosto de 2017 a las 0:40
• Por una corazonada, puse en la lista negra el controlador amdgpu por enlace y luego reinicié. El sistema funcionó bien excepto por una tasa de respuesta efectiva de 2Hz. Intenté incluir Radeon en la misma lista negra pero luego el sistema no arranca. Tuve que ir al mes de recuperación.de para restablecerlo. - FyFAIR 22 de agosto de 2017 a las 20:36

------------Respuesta------------

Creo que puedo decir que Kubuntu 16.04.3 es compatible con MacPro6,1 sólo cuando se instala y se ejecuta con nomodeset en los parámetros del kernel (o si uno está dispuesto a reiniciar una y otra vez hasta que aparezca por casualidad).

Kubuntu 17.04 es igual pero (may) comenzó a funcionar normalmente cuando el kernel se actualizó a 4.10.0-33-generic.

Los detalles para agregar nomodeset como parámetro del kernel se pueden encontrar en ¿Cómo agrego un parámetro de arranque del kernel?

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------------Respuesta------------

Tengo el mismo problema en miMac Pro en funcionamiento, que utiliza un chip gráfico AMD Southern Islands (PCI 1002:679e). Específicamente, obtengo:

Error al inicializar Surface Manager/radeon_setup_kernel_mem falló

y luego xorg termina.

El parpadeo de la pantalla se debe a que sddm falla y se reinicia en un bucle infinito ya que no puede conectarse a xorg. Puedes encontrar más detalles usando

dmesg | grep -i sddm

y generar un seguimiento adecuado utilizando gdb. (sddm realmente debería tener mejores informes de errores en este caso).

Para mí, el problema desapareció después de actualizar al kernel 4.13.0.

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