Re: [PATCH] i386: For debugging, make the initial page table setup less forgiving.

H. Peter Anvin
2007-04-25T17:57:11Z

Eric W. Biederman wrote:
>> This patch only affects the initial page tables, which should have been
>> thrown out *way* long ago at this point.
>
> Yes. I noticed this was happening a few days ago.
> I must not have mentioned it loudly enough.

You mentioned the continued use of init_mm. This is *very* different.

What we're seeing here is that ON PSE-CAPABLE HARDWARE, we continue to
not just use the init_mm page directory, but the actual page *tables*,
which should all have been replaced with PSE large pages to begin with.

Reusing the initial page tables on non-PSE-capable hardware *sort of*
makes sense, but his hardware should not fall in that category, I don't
think? (Unless it's one of these machines that fall over if you map the
bottom 4 MB with PSE pages?)

-hpa