Re: [PATCH] X86: MM: Add PAT Type write-through in combination with mtrr

H. Peter Anvin
2013-10-28T10:56:49Z

On 10/28/2013 03:51 AM, Ingo Molnar wrote:
>>
>> If i mark the region WB and call clflush my system will crash without
>> any message, it just stop working.
>
> Yeah, I was wondering whether it's valid at all to mark IO memory as
> cacheable - with the lack of MESI transactions and all that ...
>
> So it's apparently not valid and we've got to live with WT as the
> 'best' caching/bursting method for reads.
>

On a lot of systems I'm not sure if even WT is legitimate.

-hpa