On an iBase MB890 mobo with 855GME graphics and the latest git modesetting branch, everytime an X client application quits, the screen gets reinitialised.  Every time this happens, the hardware accelerated cursor gets progressively corrupt (whilst looking initially fine when the xserver first starts).

In practice, I830ScreenInit() seems to be called every time a client quits, causing an explosion of:

(WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
(II) No APM support in BIOS or kernel
(II) intel(0): Kernel reported 104704 total, 1 used
(II) intel(0): I830CheckAvailableMemory: 418812 kB available
(**) intel(0): VideoRam: 131072 KB
(II) intel(0): Attempting memory allocation with tiled buffers and
                large DRI memory manager reservation:
(II) intel(0): Allocating 3768 scanlines for pixmap cache
(II) intel(0): Success.
(II) intel(0): Memory allocation layout:
...

in the log.  The monitor loses sync as its CRTCs are reprogrammed.  Errors concerning 'p1 out of range', swapinterval and blanking also appear during the reinitialisation:

(WW) intel(0): p1 out of range
...
(EE) DoSwapInterval: cx = 0x83692a0, GLX screen = 0x825aed0
...
(EE) intel(0): I830 Vblank Pipe Setup Failed 0.

See also http://lists.freedesktop.org/archives/xorg/2007-March/022229.html.

Attached is an Xorg.0.log showing two such reinitialisations (once after plain x11 activity, another after GLX), and the associated xorg.conf.  This is using xserver, mesa, dri and drm from git.