Re: ppc kvm: support of 64K guest page size with 4K host pagesize?

[Thomas Huth]

On 05/06/2025 08.34, Michael Tokarev wrote:
> There's a bug report filed in debian against qemu,
> https://bugs.debian.org/1107288 - saying kvm on ppc does not
> work on debian (anymore) due to qemu requesting unrealistic
> (non-existing) page size of 64K on a host which only has 4K.
>
> I don't know much about PPC, - what's the issue here? Should
> qemu use the same page size for kvm as on the host?

Looking at

 
https://gitlab.com/qemu-project/qemu/-/commit/2309832afdaf8d6451ebc2e81bace8eb8ea41293

it seems like this was done on purpose? David, do you remember why 
auto-detecting was not a good idea here?

Anyway, seems like there is a hpt-max-page-size property that could be used 
to set the value manually - maybe you could suggest that to the user as a 
work-around?

 Thomas