Package: xserver-xorg-core


The bug seems not related to xorg but to the fvwm window manager crash. I ran the window manager with gdb and was able to reliably make it crash by some mouse activity.


(gdb) run
Starting program: /usr/bin/fvwm
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Detaching after fork from child process 4851]
[Detaching after vfork from child process 4864]
Warning: Arg --fvwm-icons is obsolete and ignored
Python module python-xdg not found.fvwm: ../../src/xcb_io.c:626: _XAllocID: Assertion `ret != inval_id' failed.

Program received signal SIGABRT, Aborted.
__pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
44      ./nptl/pthread_kill.c: No such file or directory.
(gdb) bt
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
#1  0x00007ffff6ca9d2f in __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
#2  0x00007ffff6c5aef2 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff6c45472 in __GI_abort () at ./stdlib/abort.c:79
#4  0x00007ffff6c45395 in __assert_fail_base
    (fmt=0x7ffff6db9a70 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x7ffff7b75b2a "ret != inval_id", file=file@entry=0x7ffff7b75a9b "../../src/xcb_io.c", line=line@entry=626, function=function@entry=0x7ffff7b75ef0 "_XAllocID") at ./assert/assert.c:92
#5  0x00007ffff6c53df2 in __GI___assert_fail (assertion=0x7ffff7b75b2a "ret != inval_id", file=0x7ffff7b75a9b "../../src/xcb_io.c", line=626, function=0x7ffff7b75ef0 "_XAllocID") at ./assert/assert.c:101
#6  0x00007ffff7b02443 in  () at /usr/lib/x86_64-linux-gnu/libX11.so.6
#7  0x00007ffff7e56558 in XRenderCreatePicture () at /usr/lib/x86_64-linux-gnu/libXrender.so.1
#8  0x00007ffff7f9e5b6 in  () at /usr/lib/x86_64-linux-gnu/libXft.so.2
#9  0x00007ffff7f9ec95 in XftDrawGlyphs () at /usr/lib/x86_64-linux-gnu/libXft.so.2
#10 0x00007ffff7f9f2ad in XftDrawStringUtf8 () at /usr/lib/x86_64-linux-gnu/libXft.so.2
#11 0x00005555555ff843 in  ()
#12 0x00005555555e6dfb in  ()
#13 0x00005555555a5fff in  ()
#14 0x00005555555a7ba4 in  ()
#15 0x0000555555588dba in  ()
#16 0x000055555558c4eb in  ()
#17 0x000055555558c66c in  ()
#18 0x0000555555600189 in  ()
#19 0x000055555560020f in  ()
#20 0x00007ffff7add9da in XCheckIfEvent () at /usr/lib/x86_64-linux-gnu/libX11.so.6
#21 0x0000555555600b62 in  ()
#22 0x0000555555600cb7 in  ()
#23 0x000055555558d58a in  ()
#24 0x00005555555bfb2f in  ()
#25 0x00005555555a92ca in  ()
#26 0x00005555555a9bf4 in  ()
#27 0x00005555555c7f29 in  ()
#28 0x0000555555589d43 in  ()
#29 0x000055555558c4eb in  ()
#30 0x000055555558c5e4 in  ()
#31 0x00005555555674f7 in  ()
#32 0x00007ffff6c4618a in __libc_start_call_main (main=main@entry=0x555555565a90, argc=argc@entry=1, argv=argv@entry=0x7fffffffe4d8) at ../sysdeps/nptl/libc_start_call_main.h:58
#33 0x00007ffff6c46245 in __libc_start_main_impl (main=0x555555565a90, argc=1, argv=0x7fffffffe4d8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe4c8) at ../csu/libc-start.c:381
#34 0x0000555555568631 in  ()
(gdb)