Re: [PATCH v7 0/7] KVMPPC driver to manage secure guest pages

[Paul Mackerras <paulus@ozlabs.org>]

On Thu, Aug 22, 2019 at 03:56:13PM +0530, Bharata B Rao wrote:
> Hi,
> 
> A pseries guest can be run as a secure guest on Ultravisor-enabled
> POWER platforms. On such platforms, this driver will be used to manage
> the movement of guest pages between the normal memory managed by
> hypervisor(HV) and secure memory managed by Ultravisor(UV).
> 
> Private ZONE_DEVICE memory equal to the amount of secure memory
> available in the platform for running secure guests is created.
> Whenever a page belonging to the guest becomes secure, a page from
> this private device memory is used to represent and track that secure
> page on the HV side. The movement of pages between normal and secure
> memory is done via migrate_vma_pages(). The reverse movement is driven
> via pagemap_ops.migrate_to_ram().
> 
> The page-in or page-out requests from UV will come to HV as hcalls and
> HV will call back into UV via uvcalls to satisfy these page requests.
> 
> These patches are against hmm.git
> (https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/log/?h=hmm)
> 
> plus
> 
> Claudio Carvalho's base ultravisor enablement patchset v6
> (https://lore.kernel.org/linuxppc-dev/20190822034838.27876-1-cclaudio@linux.ibm.com/T/#t)

How are you thinking these patches will go upstream?  Are you going to
send them via the hmm tree?

I assume you need Claudio's patchset as a prerequisite for your series
to compile, which means the hmm maintainers would need to pull in a
topic branch from Michael Ellerman's powerpc tree, or something like
that.

Paul.