Re: [PATCH v5 3/3] xen/ppc: mm-radix: Allocate all paging structures at runtime

[Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx>]

Hi Jan,

On 9/30/24 10:20 AM, Jan Beulich wrote:
> On 27.09.2024 00:24, Shawn Anastasio wrote:
>> In the initial mm-radix implementation, the in-memory partition and
>> process tables required to configure the MMU, as well as the page tables
>> themselves were all allocated statically since the boot allocator was
>> not yet available.
>>
>> Now that it is, allocate these structures at runtime and bump the size
>> of the Process Table to its maximum supported value (on POWER9).
>>
>> Signed-off-by: Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx>
> 
> On the assumption that the (theoretical only?) case of there being gaps
> in [min_alloc_mfn,max_alloc_mfn] if deemed okay, with it being just more
> memory being mapped in such a case:
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>

Sorry for the late response on this. Your assumption is correct -- in
the case that there are gaps in the allocated region, it will just
result in more memory than is strictly necessary being mapped, and given
the constraints here I'm fine with that tradeoff.

> Jan

Thanks,
Shawn