7.2-PRERELEASE X-server hang in "drmwtq"

[Artem Kim]

Hi.

In last time, I have a problem with stability
on my system:

7.2-PRERELEASE Thu Apr 2 20:20:31 MSD 2009 amd64 (UP); ati 9800-XT

From time to time the x-server go in "drmwtq" state if the AIGLX is enabled.
This usually happens when creating a new window.

If I setup hw.dri.0.debug to "1", I get a lot of
messages:

[drm: pid1469: drm_ioctl] pid = 1469, cmd = 0x80046457, nr = 0x57, dev 
0xffffff0001306800, auth = 1
[drm: pid1469: drm_ioctl] returning -1

I can see a recurring message in in ktrace:

1469 Xorg PSIG SIGALRM caught handler = 0x4dca90 mask = 0x0 code = 0x0
1469 Xorg CALL sigreturn (0x7fffffffe5b0)
1469 Xorg RET sigreturn JUSTRETURN
1469 Xorg CALL ioctl (0xa, 0x80046457, 0x8156e807c)
1469 Xorg RET ioctl RESTART

The problems started after vblank rework in the STABLE.
The first time I got a panic when i try to restart or shutdown x-server,
but the problem with panic was solved (for me ;)) quickly.

I am ready to provide any additional information.

Many thanks for your work.