2000-11-09 16:07:34

by Tigran Aivazian

[permalink] [raw]
Subject: why do we need pg1?

Hi,

The code which sets up the page table at pg0 (in head.S) goes all the way
until it hits empty_zero_page so I don't understand why we need the label
pg1 in between, since it is never referred to by any other code?

Also, is the comment in asm/pgtable.h

/* page table for 0-4MB for everybody */
extern unsigned long pg0[1024];

true or false? Isn't it for 0-8M as head.S claims?

Regards,
Tigran



2000-11-09 16:40:36

by Tigran Aivazian

[permalink] [raw]
Subject: Re: why do we need pg1?

On Thu, 9 Nov 2000, Tigran Aivazian wrote:

> Hi,
>
> The code which sets up the page table at pg0 (in head.S) goes all the way
> until it hits empty_zero_page so I don't understand why we need the label
> pg1 in between, since it is never referred to by any other code?
>
> Also, is the comment in asm/pgtable.h
>
> /* page table for 0-4MB for everybody */
> extern unsigned long pg0[1024];
>
> true or false? Isn't it for 0-8M as head.S claims?

after a minute of thought, the answer to the second question is now
obvious, but the answer to the first one still is _not_.

Regards,
Tigran