Re: vm changes from linux-2.6.14 to linux-2.6.15

Andrew Morton
2007-04-30T21:54:14Z

On Mon, 30 Apr 2007 22:36:27 +0100 (BST)
Mark Fortescue <mark@mtfhpc.demon.co.uk> wrote:

> Hi all,
>
> I have tracked down a failure to successfully load/run the init task on my
> Sparcstation 1 clone (SS1) and Sparcstation 2 (SS2), sparc32 sun4c
> systems, to a patch:
>
> commit 1a44e149084d772a1bcf4cdbdde8a013a8a1cfde.
> [PATCH] .text page fault SMP scalability optimization
>
> Removing this patch fixes the issue and allows me to use kernels later
> than v2.5.14. (tested using linux-2.6.20.9).
>
> Given the comment provided by the git bisect, backing out this patch will
> probably have undesirable conseqnences for other platforms (especially
> powerpc64) so, if an architecture independent solution is not available,
> some/all of the code in handle_pte_fault() in mm/memory.c will need be to
> made architecture dependent.
>
> I am not sufficiently familear with the how the SS1/SS2 mmu works and how
> the linux memory management system works to understand why this patch
> prevents my sun4c SS1/SS2 systems from working.
>
> Advice and help on the approch to take and any code changes regarding this
> issue would be most welcome.
>

Interesting - thanks for working that out. Let's keep linux-mm on cc please.