Re: [PATCH 2/2] x86: mtrr_cleanup try gran_size to less than 1M

H. Peter Anvin
2008-10-03T07:39:20Z

Ingo Molnar wrote:
> * J.A. Magallón <jamagallon@ono.com> wrote:
>
>> Also, on a 64 bit box with 4Gb, it gives this:
>>
>> cicely:~# cat /proc/mtrr
>> reg00: base=0x00000000 ( 0MB), size=4096MB: write-back, count=1
>> reg01: base=0x100000000 (4096MB), size=1024MB: write-back, count=1
>> reg02: base=0x140000000 (5120MB), size= 512MB: write-back, count=1
>> reg03: base=0x160000000 (5632MB), size= 256MB: write-back, count=1
>> reg04: base=0x80000000 (2048MB), size=2048MB: uncachable, count=1
>>
>> Patch below cleans up formatting, with space for big bases and sizes (64 Gb).
>
> applied to tip/x86/mtrr, thanks!
>
>> +++ arch/x86/kernel/cpu/mtrr/if.c 2008-10-03 00:22:34.000000000 +0200
>> @@ -16,7 +16,7 @@
>> static const char *const mtrr_strings[MTRR_NUM_TYPES] =
>> {
>> "uncachable", /* 0 */
>> - "write-combining", /* 1 */
>> + "write-combine", /* 1 */
>
> hm, maybe this bit could confuse versions of Xorg that modifies
> /proc/mtrr - i.e. this could be part of the ABI towards user-space.
> We'll see.
>

This *IS* part of the ABI toward userspace, although I think Xorg uses
the ioctl() interface.

-hpa