Re: Page Colouring (was: 2.6.0 Huge pages not working as expected)

Rusty Russell
2003-12-30T02:06:20Z

On Mon, 29 Dec 2003 02:23:19 -0800
William Lee Irwin III <wli@holomorphy.com> wrote:

> The fact merely elevating PAGE_SIZE breaks numerous things makes me
> rather suspicious of claims that minimalistic patches can do likewise.

Can you give an example?

One approach is to simply present a larger page size to userspace w/
getpagesize(). This does break ELF programs which have been laid out assuming
the old page size (presumably they try to mprotect the read-only sections).
On PPC, the ELF ABI already insists on a 64k boundary between such sections,
and maybe for others you could simply round appropriately and pray, or do
fine-grained protections (ie. on real pagesize) for that one case.

Rusty.
--
there are those who do and those who hang on and you don't see too
many doers quoting their contemporaries. -- Larry McVoy