serious dcop deadlock

[Charles Samuels]

I have repeatedly encountered a bug in which kwin would deadlock hard, 
rendering the entire machine unstoppable. ctrl-alt-bs, ctrl-alt-f1 would do 
nothing.

If I kill kwin and restart it, the restarted one gets stuck in a similar way. 
If I kill dcopserver, then all client apps find that dcopserver has exited, 
and the session ends, kdm starts up again, and the system goes back to 
normal.

the Debian packagers had this brilliant idea of stripping dcopserver, so my 
backtrace to that is totally unhelpful, but I'll switch to a debug one and 
attempt to reproduce it again (it's totally spurious)

I'd usually avoid sending bug reports to kde-core-devel, but this I think 
requires a little attention.

Charles
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GNU gdb 6.4.90-debian
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This GDB was configured as "i486-linux-gnu"...(no debugging symbols found)
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".

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0xffffe410 in __kernel_vsyscall ()
(gdb) bt
#0  0xffffe410 in __kernel_vsyscall ()
#1  0xb7d5f583 in read () from /lib/tls/i686/cmov/libc.so.6
#2  0xb6b2343e in _kde_IceTransGetConnectionNumber ()
   from /usr/lib/libDCOP.so.4
#3  0xb6b230ff in _kde_IceTransRead () from /usr/lib/libDCOP.so.4
#4  0xb6b1cfdf in _kde_IceRead () from /usr/lib/libDCOP.so.4
#5  0xb6b216ef in KDE_IceProcessMessages () from /usr/lib/libDCOP.so.4
#6  0xb6b19f4a in KDE_IceOpenConnection () from /usr/lib/libDCOP.so.4
#7  0xb6b1448e in DCOPClient::attachInternal () from /usr/lib/libDCOP.so.4
#8  0xb6b14cbb in DCOPClient::attach () from /usr/lib/libDCOP.so.4
#9  0xb78d8edd in KCheckAccelerators::eventFilter ()
   from /usr/lib/libkdecore.so.4
#10 0xb78d936e in KNotifyClient::event () from /usr/lib/libkdecore.so.4
#11 0xb686754a in KWinInternal::Notify::raise ()
   from /usr/lib/libkdeinit_kwin.so
#12 0xb687c00b in KWinInternal::Workspace::setCurrentDesktop ()
   from /usr/lib/libkdeinit_kwin.so
#13 0xb6888df7 in KWinInternal::Workspace::init ()
   from /usr/lib/libkdeinit_kwin.so
#14 0xb6889bcd in KWinInternal::Workspace::Workspace ()
   from /usr/lib/libkdeinit_kwin.so
#15 0xb6889e2c in KWinInternal::Application::Application ()
   from /usr/lib/libkdeinit_kwin.so
#16 0xb688a2c3 in kdemain () from /usr/lib/libkdeinit_kwin.so
#17 0xb7f35524 in kdeinitmain () from /usr/lib/kde3/kwin.so
#18 0x0804e9d7 in ?? ()
#19 0x00000001 in ?? ()
#20 0x0806a838 in ?? ()
#21 0x00000001 in ?? ()
#22 0x00000000 in ?? ()
(gdb) q
The program is running.  Quit anyway (and detach it)? (y or n) 
Please answer y or n.
The program is running.  Quit anyway (and detach it)? (y or n) Detaching from program: /usr/bin/kdeinit, process 12162