AW: Re: __setup_cpu_be problem

[Geoff Levand]

Hollis Blanchard wrote:
> On Tue, 2006-02-14 at 10:22 -0800, Geoff Levand wrote:
>> 
>> Sorry about changing my mind on this Ben, but after reading the Book 4
>> docs on page sizes I see that each partition can have independent
>> page size settings.  I made the wrong assumption that all partitions
>> needed the same size setting.  Based on this, and on Arnd's comments,
>> I think in general we will need to setup page sizes in the kernel. 
> 
> On Tue, 2006-02-14 at 15:27 -0600, Olof Johansson wrote: 
>> 
>> Isn't this something that should be configured in the hypervisor /
>> partition firmware on the machine then, instead of hacked into the
>> kernel? The hypervisor would of course switch HID contents when
>> dispatching different partitions, if needed.
> 
> I agree with Olof; I don't follow the original leap of logic.
> 
> If every partition can have independent page size settings, and
> especially if HID6 is a hypervisor-privileged resource as mentioned
> earlier, then the hypervisor needs to set it. Only the hypervisor can
> restore each partition's different HID6 value when it switches between
> them...
> 

I guess what I am thinking of are cases like when the firmware has no
clue and just uses defaults, or when the firmware or hypervisor
expect the kernel to set what sizes work best for it.  In these
cases a change needs to be initiated by the kernel.

-Geoff