Re: unify pagetable accessors patch causes double fault II

Ingo Molnar
2008-01-14T16:57:01Z

* Jeremy Fitzhardinge <jeremy@goop.org> wrote:

>> This is with PAE and seems to only happen with enough RAM (6GB); a
>> 2GB system boots. 64bit also works.
>
> Thanks, I'll have a close look at it. Presumably a pfn is getting
> truncated to 20/32-bits somewhere.

would be nice to have some debugging apparatus for bugs like this.
Perhaps artificially add a large pfn, then convert/unconvert, then
subtract it and expect the whole transformation to be an identity
mapping? This way we could simulate most of the effects of >4GB RAM,
right?

Ingo