On Sun, Aug 15, 2010 at 6:27 PM, Walter Dnes <waltd...@waltdnes.org> wrote: > I'm running 64-bit Gentoo on an Intel 4-core i3 with an Intel integrated > graphics controller. An excerpt from dmesg follows, with the video- > related stuff. Note the two lines that I've split off. They mention > the mtrr type mismatch and the allocation failure. Is this a problem > and if so, what do I do about it?
... > [ 0.608643] mtrr: type mismatch for d0000000,10000000 old: write-back new: > write-combining > [ 0.608725] [drm] MTRR allocation failed. Graphics performance may suffer. I had a similar message, it was there because of the fact that i specified the wrong (or failed to specify?) mtrr method in my kernel boot parameters for the framebuffer. I'm using uvesafb and in kernel documentation (/usr/src/linux/Documentation/fb/uvesafb.txt) it explains the values and even gives an example of this error and what to do about it: <cut> mtrr:n Setup memory type range registers for the framebuffer where n: 0 - disabled (equivalent to nomtrr) (default) 1 - uncachable 2 - write-back 3 - write-combining 4 - write-through If you see the following in dmesg, choose the type that matches the old one. In this example, use "mtrr:2". ... mtrr: type mismatch for e0000000,8000000 old: write-back new: write-combining ... </cut> After I changed my mtrr setting in grub's config & rebooted, the error message went away. HTH :)