Trying to track down the source of system crash when in a certain full screen OpenGL game, I found this in dmesg:
Googling this error showed a possible fix - correcting the MTRR entries in /proc/mtrr.
[drm] MTRR allocation failed. Graphics performance may suffer.
These appear to be wrong, as my mobo is Intel DG45FC with 256mb as video ram.
reg00: base=0x000000000 ( 0MB), size= 4096MB, count=1: write-back
reg01: base=0x0bdd00000 ( 3037MB), size= 1MB, count=1: write-through
reg02: base=0x0bde00000 ( 3038MB), size= 2MB, count=1: uncachable
reg03: base=0x0be000000 ( 3040MB), size= 32MB, count=1: uncachable
reg04: base=0x0c0000000 ( 3072MB), size= 1024MB, count=1: uncachable
reg05: base=0x100000000 ( 4096MB), size= 1024MB, count=1: write-back
reg06: base=0x13c000000 ( 5056MB), size= 64MB, count=1: uncachable
The fix is described in the file mtrr.txt which is shipped with the kernel, in my case:
00:02.0 VGA compatible controller: Intel Corporation 4 Series Chipset Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
Subsystem: Intel Corporation Device 5003
Flags: bus master, fast devsel, latency 0, IRQ 24
Memory at d0000000 (64-bit, non-prefetchable) [size=4M]
Memory at c0000000 (64-bit, prefetchable) [size=256M]
I/O ports at f1c0 [size=8]
Expansion ROM at <unassigned> [disabled]
Capabilities:  MSI: Enable+ Count=1/1 Maskable- 64bit-
Capabilities: [d0] Power Management version 2
Kernel driver in use: i915
But when I do this, I get a bash error:
echo "base=0xc0000000 size=0x10000000 type=write-combining" >| /proc/mtrr
Is there some special Suse way of doing this or something?
bash: echo: write error: Invalid argument