Nouveau - Aug 2009 - Debugging help needed

Hi,

I once had nouveau working and stable back whem 2.6.29 was released.
Nowadays, it hangs within less tahn an hours work. The symptom is that 
the mouse moves, but no other updates to the screen. The machine is
otherwise working mostly ok so I can ssh to it. The "issue" I have is 
that there is nothing interesting (afaict) in any log. Nothing in 
Xog.0.log, nothing in dmesg.

The one intersting thing I've noticed is that with drm debuging on I get 
a ton of these on dmesg:

host [drm:drm_ioctl], pid=2391, cmd=0x40086485, nr=0x85, dev 0xe200, auth=1

And at, or around the hang, there seem to be a an increase of:

host [drm:drm_ioctl], ret = fffffff5

Not particilarly enlighening to the uninitiated.

Any ideas how to debug these hangs? Are ther any tools around to e.g. 
reset the GPU?

/Anders

I wrote:
> I once had nouveau working and stable back whem 2.6.29 was released.
> Nowadays, it hangs within less tahn an hours work. The symptom is that
> the mouse moves, but no other updates to the screen. The machine is
> otherwise working mostly ok so I can ssh to it. The "issue" I
have is
> that there is nothing interesting (afaict) in any log. Nothing in
> Xog.0.log, nothing in dmesg.
I forgot to mention that I have an NV5 card:
nVidia Corporation NV5 [RIVA TNT2/TNT2 Pro] (rev 15)

/Anders

What are you using? are you using master from the nouveau kernel? git
versions for the rest? self made or prepackaged stuff?

More info is a must.

Maarten.

On Sat, 29 Aug 2009 16:08:13 +0200
Anders Eriksson <aeriksson at fastmail.fm> wrote:
> I once had nouveau working and stable back whem 2.6.29 was released.
That would be before we used a real memory manger, IIRC.
> Nowadays, it hangs within less tahn an hours work. The symptom is that 
> the mouse moves, but no other updates to the screen. The machine is
> otherwise working mostly ok so I can ssh to it. The "issue" I
have is
> that there is nothing interesting (afaict) in any log. Nothing in 
> Xog.0.log, nothing in dmesg.
> 
> The one intersting thing I've noticed is that with drm debuging on I
get
> a ton of these on dmesg:
> 
> host [drm:drm_ioctl], pid=2391, cmd=0x40086485, nr=0x85, dev 0xe200, auth=1
0x85 = DRM_COMMAND_BASE + 0x45, so this is DRM_NOUVEAU_GEM_CPU_PREP
(include/drm/nouveau_drm.h), i.e. nouveau_gem_ioctl_cpu_prep() in
drivers/gpu/drm/nouveau/nouveau_gem.c.
> And at, or around the hang, there seem to be a an increase of:
> 
> host [drm:drm_ioctl], ret = fffffff5
Okay, so it is spinning there for some reason, returning -11,
i.e. -EAGAIN. Assuming this is the return of the prep call.

That's all I can tell for now. Full kernel logs might help, you
could open a bug report with that.

-- 
Pekka Paalanen
http://www.iki.fi/pq/