Xorg crashed with SIGSEGV in BlockHandler()

[Sindhudweep Sarkar]

Not sure how this bug happened, or what driver might have caused it. I did load a kernel drm module just before x died.

ProblemType: Crash
Architecture: i386
DistroRelease: Ubuntu 9.04
ExecutablePath: /usr/bin/Xorg
Package: xserver-xorg-core 2:1.6.0-0ubuntu1
ProcAttrCurrent: unconfined
ProcCmdline: /usr/X11R6/bin/X :0 -br -audit 0 -auth /var/lib/gdm/:0.Xauth -nolisten tcp vt7
ProcEnviron:

ProcVersion: Linux version 2.6.29-020629rc7-generic (root@zinc) (gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu7)) #020629rc7 SMP Wed Mar 4 12:14:25 UTC 2009
Signal: 11
SourcePackage: xorg-server
StacktraceTop:
 ?? ()
 ?? () from /usr/lib/xorg/modules//libshadow.so
 BlockHandler ()
 WaitForSomething ()
 Dispatch ()
Title: Xorg crashed with SIGSEGV in BlockHandler()
Uname: Linux 2.6.29-020629rc7-generic i686
UserGroups:

[backtrace]
#0 0xb7855818 in ?? ()
#1 0x080c7c83 in xf86SigHandler (signo=11)
    at ../../../../hw/xfree86/common/xf86Events.c:408
 beenhere = 1
#2 <signal handler called>
#3 0x00000000 in ?? ()
#4 0xb78cffa9 in shadowRedisplay (pScreen=0xbfbc2548)
    at ../../../miext/shadow/shadow.c:61
 pBuf = <value optimized out>
 pRegion = (RegionPtr) 0xb78d135c
#5 0x08091234 in BlockHandler (pTimeout=0xbfbc2808, pReadmask=0x81f72e0)
    at ../../dix/dixutils.c:388
 i = 2
#6 0x081326f4 in WaitForSomething (pClientsReady=0x9336550)
    at ../../os/WaitFor.c:215
 i = <value optimized out>
 waittime = {tv_sec = 0, tv_usec = 78000}
 wt = (struct timeval *) 0xbfbc2800
 timeout = <value optimized out>
 clientsReadable = {fds_bits = {0 <repeats 32 times>}}
 clientsWritable = {fds_bits = {-1211354816, 159275744, 159275736,
    136208372, 159275744, 152665712, 157322224, -1211354816, 1, -1216114700,
    -1078188216, -1216142710, 159275744, 136272896, 155993836, 136208372,
    136208372, 155993828, -1078188184, 135787442, 159275744, 136274632,
    152668640, -1211359244, -1211354816, 157322224, -1078188152, -1212332618,
    -1211354816, 157322224, -1078188120, 4096}}
 curclient = <value optimized out>
 selecterr = 0
 nready = <value optimized out>
 devicesReadable = {fds_bits = {392, 136274132, -1212334988,
    134688423, 159275744, 164869568, -1212334988, -1078188288, 136208372,
    136274132, 159275744, -1211354816, -1211354816, 170951376, -1078188328,
    159296072, 392, 155993528, 155993520, 136208372, 136238304, 48,
    -1078188312, 135499169, 155993528, 136208372, -1078188248, -1211359244,
    -1211354816, 159275744, -1212334988, -1212332618}}
 now = 11735191
 someReady = 0

[lspci]
00:00.0 Host bridge [0600]: Advanced Micro Devices [AMD] RS780 Host Bridge [1022:9600]
     Subsystem: Advanced Micro Devices [AMD] RS780 Host Bridge [1022:9600]
01:05.0 VGA compatible controller [0300]: ATI Technologies Inc Radeon HD 3200 Graphics [1002:9610]
     Subsystem: Giga-byte Technology Device [1458:d000]

[Apport retracing service (apport)]

StacktraceTop:?? ()
shadowRedisplay (pScreen=0xbfbc2548)
BlockHandler (pTimeout=0xbfbc2808, pReadmask=0x81f72e0)
WaitForSomething (pClientsReady=0x9336550)
Dispatch () at ../../dix/dispatch.c:367

[Bryce Harrington (bryce)]

        (*pBuf->update)(pScreen, pBuf);

#3 0x00000000 in ?? ()

race condition? Next this bug should probably go upstream.

[Bryce Harrington (bryce)]

[This is an automatic notification.]

Hi Sindhudweep,

This bug was reported against an earlier version of Ubuntu, can you
test if it still occurs on Lucid?

Please note we also provide technical support for older versions of
Ubuntu, but not in the bug tracker. Instead, to raise the issue through
normal support channels, please see:

    http://www.ubuntu.com/support

If you are the original reporter and can still reproduce the issue on
Lucid, please run the following command to refresh the report:

  apport-collect 340299

If you are not the original reporter, please file a new bug report, so
we can work with you as the original reporter instead (you can reference
bug 340299 in your report if you think it may be related):

  ubuntu-bug xorg

If by chance you can no longer reproduce the issue on Lucid or if you
feel it is no longer relevant, please mark the bug report 'Fix Released'
or 'Invalid' as appropriate, at the following URL:

  https://bugs.launchpad.net/ubuntu/+bug/340299

[Bryce Harrington (bryce)]

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.