[PATCH v14 0/8] MTE support for KVM guest

[Steven Price]

This series adds support for using the Arm Memory Tagging Extensions
(MTE) in a KVM guest.

Changes since v13[1]:

 * Add Reviewed-by tags from Catalin - thanks!

 * Introduce a new function mte_prepare_page_tags() for handling the
   initialisation of pages ready for a KVM guest. This takes the big
   tag_sync_lock removing any race with the VMM (or another guest)
   around clearing the tags and setting PG_mte_tagged.

 * The ioctl to fetch/store tags now returns the number of bytes
   processed so userspace can tell how far a partial fetch/store got.

 * Some minor refactoring to tidy up the code thanks to pointers from
   Catalin.

[1] https://lore.kernel.org/r/20210524104513.13258-1-steven.price%40arm.com

Catalin Marinas (1):
  arm64: Handle MTE tags zeroing in __alloc_zeroed_user_highpage()

Steven Price (7):
  arm64: mte: Handle race when synchronising tags
  arm64: mte: Sync tags for pages where PTE is untagged
  KVM: arm64: Introduce MTE VM feature
  KVM: arm64: Save/restore MTE registers
  KVM: arm64: Expose KVM_ARM_CAP_MTE
  KVM: arm64: ioctl to fetch/store tags in a guest
  KVM: arm64: Document MTE capability and ioctl

 Documentation/virt/kvm/api.rst             | 57 +++++++++++++++
 arch/arm64/include/asm/kvm_arm.h           |  3 +-
 arch/arm64/include/asm/kvm_emulate.h       |  3 +
 arch/arm64/include/asm/kvm_host.h          | 12 ++++
 arch/arm64/include/asm/kvm_mte.h           | 66 +++++++++++++++++
 arch/arm64/include/asm/mte-def.h           |  1 +
 arch/arm64/include/asm/mte.h               |  8 ++-
 arch/arm64/include/asm/page.h              |  6 +-
 arch/arm64/include/asm/pgtable.h           | 22 +++++-
 arch/arm64/include/asm/sysreg.h            |  3 +-
 arch/arm64/include/uapi/asm/kvm.h          | 11 +++
 arch/arm64/kernel/asm-offsets.c            |  2 +
 arch/arm64/kernel/mte.c                    | 54 ++++++++++++--
 arch/arm64/kvm/arm.c                       | 16 +++++
 arch/arm64/kvm/guest.c                     | 82 ++++++++++++++++++++++
 arch/arm64/kvm/hyp/entry.S                 |  7 ++
 arch/arm64/kvm/hyp/exception.c             |  3 +-
 arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 21 ++++++
 arch/arm64/kvm/mmu.c                       | 42 ++++++++++-
 arch/arm64/kvm/reset.c                     |  3 +-
 arch/arm64/kvm/sys_regs.c                  | 32 +++++++--
 arch/arm64/mm/fault.c                      | 21 ++++++
 include/uapi/linux/kvm.h                   |  2 +
 23 files changed, 454 insertions(+), 23 deletions(-)
 create mode 100644 arch/arm64/include/asm/kvm_mte.h

-- 
2.20.1