Dell C610 display close crashes X.org

[groot7000]

Debian testing, kernel 2.6.15.4.

Whenever I close the display while X.org is running X crashes with the following message:

   *** If unresolved symbols were reported above, they might not
   *** be the reason for the server aborting.

Backtrace:
0: /usr/bin/X11/X(xf86SigHandler+0x88) [0x8089898]
1: [0xffffe420]
2: /lib/tls/libc.so.6(__strtoul_internal+0x3f) [0xb7e209af]
3: /usr/bin/X11/X [0x80a8e92]
4: /usr/bin/X11/X(xf86HandlePMEvents+0x2e) [0x80b9dee]
5: /usr/bin/X11/X(xf86Wakeup+0x13c) [0x8089aec]
6: /usr/bin/X11/X(WakeupHandler+0x53) [0x80ca413]
7: /usr/bin/X11/X(WaitForSomething+0x191) [0x80e87c1]
8: /usr/bin/X11/X(Dispatch+0x70) [0x80c9990]
9: /usr/bin/X11/X(main+0x415) [0x80d6785]
10: /lib/tls/libc.so.6(__libc_start_main+0xd0) [0xb7e07eb0]
11: /usr/bin/X11/X [0x8070131]

Fatal server error:
Caught signal 11.  Server aborting


Please consult the The X.Org Foundation support
         at http://wiki.X.Org
 for help.
Please also check the log file at "/var/log/Xorg.0.log" for additional informati                                                                           on.

This also happens with kernel 2.6.11.12. The only other messages are:

psmouse.c: TouchPad at isa0060/serio1/input0 lost synchronization, throwing 5 bytes away.
psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1
video bus notify
psmouse.c: TouchPad at isa0060/serio1/input0 - driver resynched.
psmouse.c: TouchPad at isa0060/serio1/input0 lost synchronization, throwing 5 bytes away.
psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1
video bus notify
psmouse.c: TouchPad at isa0060/serio1/input0 - driver resynched.

This problem started as the result of an upgrade a while ago. I don't know exactly what was upgraded, since I didn't notice it immediately.

My xorg.conf is:

# XFree86 4.0 configuration by Raj Singh
# For a Dell Latitude c610 laptop
# Pretty standard except uses a 3rd party Synaptics touchpad driver
# Name this file 'XF86Config-4' and place in /etc/X11 to use

Section "ServerLayout"
        Identifier "XFree86 Configured"
        Screen      0  "Screen0" 0 0
        #InputDevice    "Trackpad0" "CorePointer"
        InputDevice     "Mouse0" "CorePointer"
        InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

# By default, Red Hat Linux 6.0 and later use xfs

Section "Files"
        FontPath "unix/:7100"
EndSection

# Module loading section

Section "Module"
        Load  "dbe"             # Double-buffering
        Load  "GLcore"          # OpenGL support
        Load  "dri"             # Direct rendering infrastructure
        Load  "glx"             # OpenGL X protocol interface
        Load  "extmod"          # Misc. required extensions
        Load  "v4l"             # Video4Linux
        # Load  "pex5"          # PHIGS for X 3D environment (obsolete)
        # Load  "record"        # X event recorder
        # Load  "xie"           # X Image Extension (obsolete)
        # You only need the following two modules if you do not use xfs.
        # Load  "freetype"       # TrueType font handler
        # Load  "type1"         # Adobe Type 1 font handler

        Load  "synaptics"       # Synaptics touchpad driver I added
EndSection

Section "InputDevice"
        Identifier  "Keyboard0"
        Driver      "keyboard"
        Option      "XkbLayout" "us"
EndSection

Section "InputDevice"
        Identifier  "Mouse0"
        Driver      "mouse"
        Option      "Device" "/dev/psaux"
        Option      "Protocol" "PS/2"
        Option      "Emulate3Buttons" "on"
        Option      "ZAxisMapping" "4 5"
EndSection

# added for Synaptics touchpad driver
# from Stefan Gmeiner (riddlebox@freesurf.ch)
Section "InputDevice"
        Identifier      "Trackpad0"
        Driver  "synaptics"
        Option  "Device"        "/dev/psaux"
        Option  "Edges"         "1900 5400 1800 3900"
        #Option "Finger"        "50 50"
        #Option "MaxTapTime"    "180"
        #Option "MaxTapMove"    "100"
        #Option "VertScrollDelta" "100"
        #Option "MinSpeed"      "0.05"
        #Option "MaxSpeed"      "0.10"
        #Option "AccelFactor"   "0.0010"
        Option  "Repeater"      "/dev/ps2mouse"
        Option  "SHMConfig"     "on"
EndSection

Section "Monitor"
        Identifier "Dell 1024X Laptop Display Panel"
        VendorName "Unknown"
        ModelName  "Unknown"
        HorizSync 31.5-48.5
        VertRefresh 59.0-75.0
        #VertRefresh 60
        Option "dpms"
EndSection

Section "Device"
        Identifier "ATI Radeon (generic)"
        Driver "radeon"
        VideoRam 16384
        BoardName "Unknown"
        # Option "CrtScreen" "True"     # Use for external monitor when docking
    # Option "nodri"
EndSection

Section "Device"
        Identifier "Linux Frame Buffer"
        Driver "fbdev"
        BoardName "Unknown"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device "ATI Radeon (generic)"
        Monitor "Dell 1024X Laptop Display Panel"
        DefaultDepth 24
        Subsection "Display"
                Depth 24
                Modes "1280x1024" "1152x864"
                # this resolution works and looks good, but refresh
                # rate is too low for my taste
                # Modes "1400x1050"
        EndSubSection
EndSection

Section "DRI"
        Mode 0666
EndSection

If I start X, and switch to a different virtual terminal not running X, it doesn't crash.

Any ideas?

[groot7000]

The problem appears to be solved. Disabling the console framebuffer fixed it.