Re: [RFC PATCH 0/5] target/arm: Add MTE support to KVM guest

[Haibo Xu]

On Tue, 16 Feb 2021 at 19:20, Peter Maydell <peter.maydell@linaro.org> wrote:
>
> Adding the migration maintainers to the cc list, because
> the real meat of this patchset is "how should the migration
> of MTE tags be integrated into the migration/ram.c code",
> which is pretty well out of my area of expertise...
>
> thanks
> -- PMM
>

Hi Peter,

Thanks for cc-ing to the related maintainers!

Regards,
Haibo

> On Mon, 8 Feb 2021 at 03:20, Haibo Xu <haibo.xu@linaro.org> wrote:
> >
> > This series add support for MTE(Memory Tagging Extension)[1]
> > in KVM guest. It's based on Steven Price's kernel KVM patches
> > V7[2], and has been tested to ensure that test case[3] can be
> > passed in a KVM guest. Basic pre-copy migration test also passed
> > between two MTE enabled kvm guest.
> >
> > This is a RFC patch series becuase:
> > (1) Need to add some arm MTE specific codes to the ram migration
> >     loop. There may be better way to do that in a more abstract way.
> > (2) Only pre-copy migration is supported and tested currently,
> >     post-copy as well as compress/zero page migration are still WIP.
> >
> > All kinds of feedbacks are very welcomed, especially for the migration
> > support.
> >
> > Note:
> > (1) To support MTE migration, tags for one page are appended to
> >     the page data during ram save iteration which make it easier
> >     to sync the page data and tags.
> >
> > [1] https://community.arm.com/developer/ip-products/processors/b/
> >     processors-ip-blog/posts/enhancing-memory-safety
> > [2] https://lwn.net/Articles/842827/
> > [3] https://elixir.bootlin.com/linux/latest/source/Documentation/
> >     arm64/memory-tagging-extension.rst
> >
> > Haibo Xu (5):
> >   Update Linux headers with new MTE support
> >   Add basic MTE support to KVM guest
> >   Add APIs to get/set MTE tags
> >   Add migration support for KVM guest with MTE
> >   Enable the MTE support for KVM guest
> >
> >  hw/arm/virt.c             | 44 +++++++++++++-------
> >  include/hw/arm/virt.h     |  2 +
> >  include/migration/misc.h  |  1 +
> >  linux-headers/linux/kvm.h | 15 +++++++
> >  migration/ram.c           | 86 ++++++++++++++++++++++++++++++++++++++-
> >  target/arm/cpu.c          |  2 +-
> >  target/arm/kvm.c          |  9 ++++
> >  target/arm/kvm64.c        | 31 ++++++++++++++
> >  target/arm/kvm_arm.h      |  2 +
> >  9 files changed, 176 insertions(+), 16 deletions(-)