[v4,0/2] MTE support for KVM guest

Message

Steven Price Oct. 26, 2020, 3:57 p.m. UTC

This series adds support for Arm's Memory Tagging Extension (MTE) to
KVM, allowing KVM guests to make use of it. This builds on the existing
user space support already in v5.10-rc1, see [1] for an overview.

[1] https://lwn.net/Articles/834289/

Changes since v3[2]:

 * Rebased on v5.10-rc1 (required updating KVM_CAP number).

 * Clarified redundant test for system_supports_mte() with a comment.

 * Added Reviewed-by tags from Andrew - thanks!

[2] https://lore.kernel.org/r/20200925093607.3051-1-steven.price%40arm.com

Haibo plans to start looking at the QEMU support for this. I believe
what is in this series should be sufficient, but there is still some
concern that we need more kernel support for easily accessing the tags
for migrating the VM. I don't expect any extra support to change the
interfaces defined here, but rather build on them. My only reservation
would be whether we want to expose the KVM_CAP before everything is
ready.

Steven Price (2):
  arm64: kvm: Save/restore MTE registers
  arm64: kvm: Introduce MTE VCPU feature

 arch/arm64/include/asm/kvm_emulate.h       |  3 +++
 arch/arm64/include/asm/kvm_host.h          |  7 +++++++
 arch/arm64/include/asm/sysreg.h            |  3 ++-
 arch/arm64/kvm/arm.c                       |  9 +++++++++
 arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 14 ++++++++++++++
 arch/arm64/kvm/mmu.c                       | 20 ++++++++++++++++++++
 arch/arm64/kvm/sys_regs.c                  | 20 +++++++++++++++-----
 include/uapi/linux/kvm.h                   |  1 +
 8 files changed, 71 insertions(+), 6 deletions(-)