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

From
Bharata B Rao <hidden>
Date
2019-08-23 06:58:16
Also in
linux-mm
Reply to
Paul Mackerras, 2019-08-23
On Fri, Aug 23, 2019 at 02:17:47PM +1000, Paul Mackerras wrote:
On Thu, Aug 22, 2019 at 03:56:13PM +0530, Bharata B Rao wrote:
quoted
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 (local))
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.
I was hoping that changes required from hmm.git would hit upstream soon,
will reflect in  mpe's powerpc tree at which time these patches can go
via powerpc tree along with or after Claudio's patchset.

Though this depends on migrate_vma and memremap changes that
happen to be in hmm.git, this is majorly a kvmppc change. Hence I thought
it would be appropriate for this to go via your or mpe's tree together
with required dependencies.

Regards,
Bharata.
Thread (25 messages) 25 messages, 5 authors, last reply 2019-09-06
Keyboard shortcuts
hback out one level
jnext message in thread / next series-diff position
kprevious message in thread / previous series-diff position
ldrill in
Escclose help / fold thread tree
?toggle this help