Xdmx segfault

[Daniel]

Binary package hint: xdmx

I've been working on getting Xdmx running across 2 Ubuntu machines which seems impossible. It seems to startup but eventually dies and dmesg shows that

daniel@gambit:~$ startx /usr/bin/twm -- /usr/bin/Xdmx :1 -display 10.0.2.60:0 -display 10.0.2.61:0 -ignorebadfontpaths +xinerama -noglxproxy
(II) dmx: Generation: 1
(II) dmx: DMX version: 1.2.20070424 (DMX Project)
(II) dmx: DMX Build OS: Linux 2.6.24-19-server i686 (Ubuntu)
(II) dmx: DMX Build Compiler: gcc 4.3.2
(II) dmx: DMX Execution OS: Linux 2.6.27-11-generic #1 SMP Thu Jan 29 19:24:39 UTC 2009
(II) dmx: DMX Execution Host: gambit
(II) dmx: MAXSCREENS: 16
(II) dmx: Using configuration from command line
(II) dmx: Added 10.0.2.60:0 at 0 0
(II) dmx: Added 10.0.2.61:0 right of 10.0.2.60:0

(II) dmx[o0/10.0.2.60:0]: No Xdmx server running on backend
(II) dmx[o0/10.0.2.60:0]: Name of display: 10.0.2.60:0.0
(II) dmx[o0/10.0.2.60:0]: Version number: 11.0
(II) dmx[o0/10.0.2.60:0]: Vendor string: The X.Org Foundation
(II) dmx[o0/10.0.2.60:0]: Vendor release: 10502000
(II) dmx[o0/10.0.2.60:0]: Dimensions: 2560x1024 pixels
(II) dmx[o0/10.0.2.60:0]: 7 depths on screen 0: 24,1,4,8,15,16,32
(II) dmx[o0/10.0.2.60:0]: Depth of root window: 24 planes (24)
(II) dmx[o0/10.0.2.60:0]: Number of colormaps: 1 min, 1 max
(II) dmx[o0/10.0.2.60:0]: Options: backing-store no, save-unders no
(II) dmx[o0/10.0.2.60:0]: Window Manager running: yes
(**) dmx[o0/10.0.2.60:0]: Window manager running -- colormaps not supported
(II) dmx[o0/10.0.2.60:0]: 2560x1024+0+0 on 2560x1024 at depth=24, bpp=32
(II) dmx[o1/10.0.2.61:0]: No Xdmx server running on backend
(II) dmx[o1/10.0.2.61:0]: Name of display: 10.0.2.61:0.0
(II) dmx[o1/10.0.2.61:0]: Version number: 11.0
(II) dmx[o1/10.0.2.61:0]: Vendor string: The X.Org Foundation
(II) dmx[o1/10.0.2.61:0]: Vendor release: 10502000
(II) dmx[o1/10.0.2.61:0]: Dimensions: 1280x1024 pixels
(II) dmx[o1/10.0.2.61:0]: 7 depths on screen 0: 16,1,4,8,15,24,32
(II) dmx[o1/10.0.2.61:0]: Depth of root window: 16 planes (16)
(II) dmx[o1/10.0.2.61:0]: Number of colormaps: 1 min, 1 max
(II) dmx[o1/10.0.2.61:0]: Options: backing-store no, save-unders no
(II) dmx[o1/10.0.2.61:0]: Window Manager running: yes
(**) dmx[o1/10.0.2.61:0]: Window manager running -- colormaps not supported
(II) dmx[o1/10.0.2.61:0]: 1280x1024+0+0 on 1280x1024 at depth=16, bpp=16
(II) dmx[o1/10.0.2.61:0]: 0x21 TrueColor 16b 6b/rgb 64 0xf800 0x07e0 0x001f *
(II) dmx[o1/10.0.2.61:0]: 0x22 DirectColor 16b 6b/rgb 64 0xf800 0x07e0 0x001f
(II) dmx[o1/10.0.2.61:0]: 0x6a TrueColor 32b 8b/rgb 256 0xff0000 0xff00 0x00ff
(II) dmx[o0/10.0.2.60:0]: DPMS 1.1 (on, enabled, 0 0 0)
(II) dmx[o1/10.0.2.61:0]: DPMS 1.1 (on, enabled, 0 0 0)
(II) dmx[o0/10.0.2.60:0]: (request) s=2560x1024+0+0 r=2560x1024+0+0 @0,0 (0) (be=2560x1024 depth=24 bpp=32)
(II) dmx[o1/10.0.2.61:0]: (request) s=1280x1024+0+0 r=1280x1024+0+0 @0,0 (1) (be=1280x1024 depth=16 bpp=16)
(II) dmx[o0/10.0.2.60:0]: s=2560x1024+0+0 r=2560x1024+0+0 @0,0 (be=2560x1024 depth=24 bpp=32)
(II) dmx[o1/10.0.2.61:0]: s=1280x1024+0+0 r=1280x1024+0+0 @2560,0 (be=1280x1024 depth=16 bpp=16)
(II) dmx: Using 3840x1024 as global bounding box
(II) dmx: XSync batching with 100 ms interval
(II) dmx: Shadow framebuffer support disabled
giving up.
xinit: Connection refused (errno 111): unable to connect to X server
xinit: No such process (errno 3): Server error.

Dmesg shows:
[1380277.838912] Xdmx[20155]: segfault at 4 ip 0807bec5 sp bf9f6680 error 6 in Xdmx[8048000+170000]

The problem exists even though I try on different types of hardware (Nvidia vs Intel vs VMware gfx) and I've just seen that the problem still exists on the latest 9.04 alpha with updates available today.

daniel@ubuntu1:~$ startx /usr/bin/twm -- /usr/bin/Xdmx :3 -display 10.0.2.87:0 -display 10.0.2.88:0 -ignorebadfontpaths +xinerama
(II) dmx: Generation: 1
(II) dmx: DMX version: 1.2.20070424 (DMX Project)
(II) dmx: DMX Build OS: Linux 2.6.24-19-server i686 (Ubuntu)
(II) dmx: DMX Build Compiler: gcc 4.3.3
(II) dmx: DMX Execution OS: Linux 2.6.28-4-generic #10-Ubuntu SMP Mon Jan 12 19:35:29 UTC 2009
(II) dmx: DMX Execution Host: ubuntu1
(II) dmx: MAXSCREENS: 16
(II) dmx: Using configuration from command line
(II) dmx: Added 10.0.2.87:0 at 0 0
(II) dmx: Added 10.0.2.88:0 right of 10.0.2.87:0
(II) dmx[o0/10.0.2.87:0]: No Xdmx server running on backend
(II) dmx[o0/10.0.2.87:0]: Name of display: 10.0.2.87:0.0
(II) dmx[o0/10.0.2.87:0]: Version number: 11.0
(II) dmx[o0/10.0.2.87:0]: Vendor string: The X.Org Foundation
(II) dmx[o0/10.0.2.87:0]: Vendor release: 10599902
(II) dmx[o0/10.0.2.87:0]: Dimensions: 1280x720 pixels
(II) dmx[o0/10.0.2.87:0]: 7 depths on screen 0: 24,1,4,8,15,16,32
(II) dmx[o0/10.0.2.87:0]: Depth of root window: 24 planes (24)
(II) dmx[o0/10.0.2.87:0]: Number of colormaps: 1 min, 1 max
(II) dmx[o0/10.0.2.87:0]: Options: backing-store no, save-unders no
(II) dmx[o0/10.0.2.87:0]: Window Manager running: yes
(**) dmx[o0/10.0.2.87:0]: Window manager running -- colormaps not supported
(II) dmx[o0/10.0.2.87:0]: 1280x720+0+0 on 1280x720 at depth=24, bpp=32
(II) dmx[o0/10.0.2.87:0]: 0x21 TrueColor 24b 8b/rgb 256 0xff0000 0xff00 0x00ff *
(II) dmx[o0/10.0.2.87:0]: 0x3b TrueColor 32b 8b/rgb 256 0xff0000 0xff00 0x00ff

(II) dmx[o1/10.0.2.88:0]: No Xdmx server running on backend
(II) dmx[o1/10.0.2.88:0]: Name of display: 10.0.2.88:0.0
(II) dmx[o1/10.0.2.88:0]: Version number: 11.0
(II) dmx[o1/10.0.2.88:0]: Vendor string: The X.Org Foundation
(II) dmx[o1/10.0.2.88:0]: Vendor release: 10599902
(II) dmx[o1/10.0.2.88:0]: Dimensions: 1280x720 pixels
(II) dmx[o1/10.0.2.88:0]: 7 depths on screen 0: 24,1,4,8,15,16,32
(II) dmx[o1/10.0.2.88:0]: Depth of root window: 24 planes (24)
(II) dmx[o1/10.0.2.88:0]: Number of colormaps: 1 min, 1 max
(II) dmx[o1/10.0.2.88:0]: Options: backing-store no, save-unders no
(II) dmx[o1/10.0.2.88:0]: Window Manager running: yes
(**) dmx[o1/10.0.2.88:0]: Window manager running -- colormaps not supported
(II) dmx[o1/10.0.2.88:0]: 1280x720+0+0 on 1280x720 at depth=24, bpp=32
(II) dmx[o1/10.0.2.88:0]: 0x21 TrueColor 24b 8b/rgb 256 0xff0000 0xff00 0x00ff *
(II) dmx[o1/10.0.2.88:0]: 0x3b TrueColor 32b 8b/rgb 256 0xff0000 0xff00 0x00ff
giving up.
xinit: Connection refused (errno 111): unable to connect to X server
xinit: No such process (errno 3): Server error.

dmesg showing
Xdmx[3966]: segfault at 89d70b04 ip 0815d13a sp bf87945c error 4 in Xdmx[8048000+171000]

I believe the problem exists in 8.04 as well but I have not tested this during the last couple of days. Would be nice to be able to use Xdmx again.

[lspci]
00:00.0 Host bridge [0600]: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge [8086:7190] (rev 01)
     Subsystem: VMware Inc Device [15ad:1976]
00:0f.0 VGA compatible controller [0300]: VMware Inc Abstract SVGA II Adapter [15ad:0405]
     Subsystem: VMware Inc Abstract SVGA II Adapter [15ad:0405]

[Bryce Harrington (bryce)]

Hi daniel-gaiottino,

Please attach the output of `lspci -vvnn`, and attach your /var/log/Xorg.0.log (and maybe Xorg.0.log.old) file from after reproducing this issue. If you've made any customizations to your /etc/X11/xorg.conf please attach that as well.

[This is an automated message. Apologies if it has reached you inappropriately; please just reply to this message indicating so.]

[Daniel (daniel-gaiottino)]

Since I'm away from my regular workplace for a few days, the following are logs from 2 virtual machines running in VMware (where the same problem exists). If this is unhelpful I can re-attach logs from my other system next week.

[Daniel (daniel-gaiottino)]

I found this today which seems to know what's going on. Not sure if it is compatible with 9.04 but I'll be trying it out with both 8.10 and 9.04 and report my findings. Perhaps there's enough information there to let you get a fix into 9.04.

[Daniel (daniel-gaiottino)]

Seems the link I meant to post in my previous comment disappeared.

http://mitros.org/p/xdmx-setup.html

[Daniel (daniel-gaiottino)]

I can confirm that getting the Debian package as the above link suggests works with Ubuntu 8.10 but the Xdmx performance is very bad and more or less unusable :-/ Maybe some fixes have been made to improve this in the new Xorg being released with 9.04. Too bad the package doesn't work.

[Bryce Harrington (bryce)]

Since this is a crash, we need a full backtrace in order to troubleshoot it. Any way we could get to to collect one? There are some xserver-specific directions at http://wiki.ubuntu.com/X/Backtracing you may be able to adapt.

[gelsonrei (gelsonrei)]

Hi Daniel or Bryce,

        I have experienced same error when try to running Xdmx across 2 identical HP tablets PCs. Can I fix it in my Ubuntu 9.10 setup?

Thanks in advance.

[gelsonrei (gelsonrei)]

My Xorg.0.log

[Timo Aaltonen (tjaalton)]

This should be fixed in lucid lynx. Please try a livecd, alpha1 should be enough. It has xserver 1.7 where dmx was fixed to work again.

[Rolf Leggewie (r0lf)]

I can confirm the segfault and I can confirm it's fixed in the lucid live cd

This was fixed in Debian upstream around September last year (see Changelog)