#484 Heavy DRI use causes lockup

MGA OpenGL (56)
Chris Metzler

This bug was originally filed as Debian bug #247756 and
tagged as an upstream issue; hence, I'm here.

System info: kernel 2.4.23, XF86 v4.3.0-7, MGA G550
video card, using the driver that came with X, *not*
using the proprietary mga_hal driver from Matrox.

I am getting lockups when running OpenGL programs.
They're not exactly reproducible, in the sense that I
cannot guarantee the lockup will occur if I do any
particular sequence of steps. However, I have noticed
that it only happens when a large amount of 3D info is
being updated -- for example, if I'm flying near the
ground of a city in FlightGear. When it occurs, the
mouse still moves the mouse cursor around; but screen
updates (like a second counter on a clock, or the
OpenGL app itself) cease, no keys have any effect
(including attempts to switch virtual consoles), and
sound ends. I don't have another machine handy, so I
don't know whether I could still ssh in; and I don't
know whether doing so and killing X would have any
effect. I suspect I wouldn't be able to ssh in, and
that the lockup is complete, because it appears that
regular notes to the system logs stop being written
(looking at the logs after reboot). I'm not sure of
that, though; and am reluctant to reproduce it and
check unless you need me to because I want to avoid
forcing crashes if possible.

At any rate, my only option is the reset button.
Inspecting the XFree86.0.log.old file after rebooting,
I find hundreds of messages like this:

(EE) MGA(0): [dri] Idle timed out, resetting engine...
(EE) MGA(0): [dri] Idle timed out, resetting engine...
(EE) MGA(0): [dri] Idle timed out, resetting engine...

. . . up until the end of the file.

I was experiencing a very similar problem under XF86
4.2 (exactly the same symptoms, but no such messages
above in the log), but waited until now to file the bug
out of advice that the Matrox drivers/dri support for X
4.2 were dated and that things might improve under 4.3.

This looks like the same bug as someone else filed
against X.org:


except I don't get it immediately at the start. The
needs to be doing a lot of rendering for it to occur. And
unlike that poster, I dunno whether I can ssh in.

It may also be the same bug as #546281 here:


I don't have any way to tell.

I would like to do anything I can to get this solved.
If there's more information you need from me, please
let me know and I'll be happy to send it your way.

Thanks for any help.