[RFC PATCH v2 0/5] target/arm: Add MTE support to KVM guest

[Haibo Xu <haibo.xu@linaro.org>]

This version is rebased against kernel patches v10, and only header
files are updated since v1[1].

This series add support for MTE(Memory Tagging Extension)[2]
in KVM guest. It's based on Steven Price's kernel KVM patches
v10[3], and has been tested to ensure that test case[4] 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://lore.kernel.org/qemu-devel/cover.1612747873.git.haibo.xu@linaro.org/
[2] https://community.arm.com/developer/ip-products/processors/b/
    processors-ip-blog/posts/enhancing-memory-safety
[3] https://patchew.org/QEMU/20210312151902.17853-1-steven.price@arm.com/
[4] 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 | 16 ++++++++
 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, 177 insertions(+), 16 deletions(-)

-- 
2.17.1