I've got a box which I recently updated to F15. Everything about it seemed rock solid perfect back on RHEL4, RHEL5, and RHEL6. This is a pre-release OEM box which I can't update BIOS because they dropped support for the motherboard so if you want a way out, blame BIOS.

After I installed F15 with gnome-shell it's the first time this box has ever done anything even slightly graphics related. On the latest distro kernels: 2.6.39-0.rc7.git6.1.fc16.x86_64 it doesn't seem to be completely crashing like my -38 based kernels, but it doesn't work smoothly. I get pauses sometimes when the box does some sort of graphicsy/3Dy operation. The pause on the screen (mouse still works just fine) lasts anywhere from 1-15 seconds. The pause always seems to be accompanied with one or more (usually more) message like:

[drm] nouveau 0000:60:00.0: vm flush timeout: 0x00000022

At this point at least the .39 kernel doesn't seem to be completely killing it, but it's hardly useable...

With a .38 kernel (kernel-2.6.38.6-26.rc1.fc15.x86_64) I originally had different problems with 2 different (both nvidia cards) talking about DMAR problem (In every case the visible result was that the screen just hung indefinitely when doing some spiffy animation). I tried intel_iommu={on,off} and eventually disabled VT-d in BIOS. That seems to have shut up the dmar messages and gave me new interesting message when the graphics hung like so:

[random snippet] [drm] nouveau 0000:60:00.0: PGRAPH - ERROR nsource: DMA_VTX_PROTECTION nstatus: PROTECTION_FAULT [drm] nouveau 0000:60:00.0: PGRAPH - ch 7 (0x001e7010) subc 7 class 0x4097 mthd 0x1dac data 0x00000000 [drm] nouveau 0000:60:00.0: PGRAPH - ERROR nsource: DMA_VTX_PROTECTION nstatus: PROTECTION_FAULT [drm] nouveau 0000:60:00.0: PGRAPH - ch 7 (0x001e7010) subc 7 class 0x4097 mthd 0x1fd8 data 0x00000001 [drm] nouveau 0000:60:00.0: PGRAPH - ERROR nsource: DMA_VTX_PROTECTION nstatus: PROTECTION_FAULT [drm] nouveau 0000:60:00.0: PGRAPH - ch 7 (0x001e7010) subc 7 class 0x4097 mthd 0x1fd8 data 0x00000001 [drm] nouveau 0000:60:00.0: PGRAPH - ERROR nsource: DMA_VTX_PROTECTION nstatus: PROTECTION_FAULT [drm] nouveau 0000:60:00.0: PGRAPH - ch 7 (0x001e7010) subc 7 class 0x4097 mthd 0x0a2c data 0x00000000 [drm] nouveau 0000:60:00.0: PGRAPH - ERROR nsource: DMA_VTX_PROTECTION nstatus: PROTECTION_FAULT [drm] nouveau 0000:60:00.0: PGRAPH - ch 7 (0x001e7010) subc 7 class 0x4097 mthd 0x1fd8 data 0x00000002 [...] [drm] nouveau 0000:60:00.0: fail pre-validate sync [drm] nouveau 0000:60:00.0: validate vram_list [drm] nouveau 0000:60:00.0: validate: -16

Is there something I can collect, do try, supply or generally be helpful to figure out why I can't seem to get reasonable video here? I think I have 3 nvidia cards here (probably all about the same age, but I haven't the foggiest really) I can get error messages from, I'll try any kernel or any suggestion people have....

thanks.

-Eric

-Eric