Bug#528994: Info received (Bug#528994: Acknowledgement (xserver-xorg-core: Corrupt mouse motion events send pointer to top-left of screen))

[sand@blarg.net]

I have managed to work my way back up the failure chain, to the point
where GDB can stop the server before the mouse moves.  The failure is
associated with a motion event of {0,0} and is_absolute of 1.

(gdb) bt
#0  xf86PostMotionEventP (device=0x84a6308, is_absolute=1, first_valuator=0, num_valuators=2, valuators=0xbfc6af7c)
    at ../../../../hw/xfree86/common/xf86Xinput.c:741
#1  0xb7a6a263 in ?? () from /usr/lib/xorg/modules/input//evdev_drv.so
#2  0x084a6308 in ?? ()
#3  0x00000001 in ?? ()
#4  0x00000000 in ?? ()
(gdb) p *valuators@num_valuators
$77 = {0, 0}

That would definitely send the pointer to {0,0}.  Unfortunately, I'm
using a mouse.  And, of course, the absolute motion event didn't show
up in my original traces because I never bothered to put a trace on
that call, because it was absolute motion.  Back to debugging evdev.