Bug#616301: xserver-xorg-video-radeon:screen goes black, system hangs after 2sec:[youtube(FF/Opera)-reset req.]

[John D. Hendrickson and Sara Darnell]

I haven't heard of many chips that won't hang given the wrong 
instructsion whether it's GPU or keyboard controller.  Sounds like more 
than a driver issue but a choice of driver issue.  How are you going to 
have it both ways without an ammount of care you have no time for?

having interrupting access / watchdog is nice if your driver can do that

Ben Hutchings wrote:
> On Sun, 2011-03-06 at 13:08 -0500, Alex Deucher wrote:
>> On Fri, Mar 4, 2011 at 8:50 PM, Ben Hutchings <ben at decadent.org.uk> wrote:
>>> On Fri, 2011-03-04 at 21:01 +0200, Faidon Liambotis wrote:
>>>> severity 616301 critical
>>>> thanks
>>> No, not unless it will affect a large proportion of users.
>>>
>>>> My system locks up whenever I click on a YouTube video link since
>>>> yesterday. I can probably live without YouTube :), but in any case this
>>>> shouldn't happen.
>>>>
>>>> This isn't a singled out case nor in exotic, possibly faulty, hardware.
>>>> It's on a standard 1½-year old Dell OptiPlex 780 desktop with a Radeon
>>>> HD card (one of the standard configurations) and this is on a stock
>>>> squeeze system.
>>>>
>>>> The findings so far seem to suggest this is a Mesa issue; I'd probably
>>>> file it under "Linux kernel bugs" (or even DoS bugs) but I'm not sure
>>>> where to properly file such bugs in the post-KMS stack world.
>>> If there is a kernel driver involved then it should be assigned to the
>>> kernel.  Even without KMS, a Mesa driver should be considered untrusted
>>> and should not be able to trigger a crash or hang.  With KMS, this
>>> applies to the X driver too.
>>>
>> With or without KMS, the userspace acceleration drivers can certainly
>> cause GPU hangs if the 3D engine is programmed with some combination
>> of commands it doesn't like.
> 
> You can't solve the halting problem but you can implement a watchdog,
> can't you?
> 
> Ben.
>