Re: unify pagetable accessors patch causes double fault II

From: Ingo Molnar
Date: Mon Jan 14 2008 - 11:57:06 EST



* Jeremy Fitzhardinge <jeremy@xxxxxxxx> 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
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