Re: [git pull] x86 PAT changes

H. Peter Anvin
2008-04-26T00:06:52Z

Linus Torvalds wrote:
>
> So why is PAT dependent on NONPROMISC_DEVMEM here?
>
> It seems pointless and wrong. Somebody might want to have both the full
> /dev/mem and PAT.
>

The problem is that that can create cached/uncached aliases, which can
cause some processors to lock up (especially AMD is known to have a lot
of errata in this area.)

-hpa