Re: [Fedora-ia64-list] kernel 2.6.16-1.2097_FC6 unbootable on Itanium

David Mosberger-Tang
2006-03-30T15:43:43Z

On 3/30/06, Jack Steiner <steiner@sgi.com> wrote:

> Is this problem unique to SN systems

No, the same will happen on all other systems (that I know of).

> The BIOS reports that most
> memory ranges support both CACHED & UNCACHED references. I _think_
> this is correct.

That's correct. The map shows the ways the page *can* be mapped, not
the way it *should* be mapped.

It's strange that ACPI would prefer to use WC when WB mapping is
possible. They definitely need to pick one way and stick with it
though. As you say, mapping the same page with different cacheability
is a no-no (and at least in theory, it should cause an MCA even on
real hardware).

--david

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