[PATCH 00/20] Huge mapping support for protected VMs

[Vincent Donnefort <vdonnefort@google.com>]

Currently, pKVM handles stage-2 mappings and ownership tracking strictly
at the PAGE_SIZE level. This series extends pKVM to support PMD_SIZE
block mappings, thereby enabling Transparent Huge Pages (THP) for
protected guests. hugetlbfs is currently unsupported as it does not
appear as swapbacked.

Summary of changes:

1. Enable host stage-2 block-level annotations:

The host stage-2 being annotated with the GFN of the guest on the
host->guest donation transitions, we allow block-level annotations to
ensure the host stage-2 mapping size matches the guest stage-2.

2. Expand ownership transition HVCs:

Enable the ownership test to work with PMD_SIZE so we can test
transitions supporting more than PAGE_SIZE.

3. Implements the `PKVM_HYP_REQ_SPLIT` hypervisor request:

Allows the hypervisor to ask the host to split a mapping. This ensures
the guest s2, pkvm_mapping tree and host s2 are always using the same
mapping size.

4. Wires up THP support for pKVM guests.

Keir Fraser (1):
  KVM: arm64: Prefault host stage-2 entries on block split

Vincent Donnefort (19):
  KVM: arm64: Propagate host stage-2 annotated entries on block split
  KVM: arm64: Allow block-level stage-2 annotation
  KVM: arm64: Use block-level annotations when setting up the host
    stage-2
  KVM: arm64: Make pKVM ownership selftest an HVC
  KVM: arm64: Add a range to __pkvm_host_share/unshare_hyp()
  KVM: arm64: Add a range to __pkvm_host_donate_guest()
  KVM: arm64: Add a range to __pkvm_host_reclaim_page_guest()
  KVM: arm64: Add a range to __pkvm_guest_share_host()
  KVM: arm64: Add a range to __pkvm_guest_unshare_host()
  KVM: arm64: Add a range to pKVM ownership selftest
  KVM: arm64: Handle huge mappings in
    __pkvm_host_force_reclaim_page_guest()
  KVM: arm64: Handle huge mappings in __pkvm_vcpu_in_poison_fault()
  KVM: arm64: pkvm: Warn on guest stage-2 block collapse
  KVM: arm64: Add pkvm_hyp_req infrastructure
  KVM: arm64: Add __pkvm_host_split_guest HVC
  KVM: arm64: Extend pKVM page ownership selftests to cover guest block
    split
  KVM: arm64: Add PKVM_HYP_REQ_SPLIT
  KVM: arm64: Raise PKVM_HYP_REQ_SPLIT on guest to host sharing
  KVM: arm64: Stage-2 huge mappings for protected VMs

 arch/arm64/include/asm/kvm_asm.h              |  12 +-
 arch/arm64/include/asm/kvm_host.h             |  19 +
 arch/arm64/include/asm/kvm_pgtable.h          |   3 +-
 arch/arm64/include/asm/kvm_pkvm.h             |  21 +-
 arch/arm64/kvm/arm.c                          |   2 +
 arch/arm64/kvm/handle_exit.c                  |   3 +
 arch/arm64/kvm/hyp/include/nvhe/mem_protect.h |  25 +-
 arch/arm64/kvm/hyp/include/nvhe/memory.h      |   5 +
 arch/arm64/kvm/hyp/include/nvhe/pkvm.h        |   6 +-
 arch/arm64/kvm/hyp/nvhe/ffa.c                 |  12 +-
 arch/arm64/kvm/hyp/nvhe/hyp-main.c            |  47 +-
 arch/arm64/kvm/hyp/nvhe/mem_protect.c         | 545 ++++++++++++------
 arch/arm64/kvm/hyp/nvhe/pkvm.c                |  59 +-
 arch/arm64/kvm/hyp/nvhe/setup.c               | 152 +++--
 arch/arm64/kvm/hyp/pgtable.c                  | 113 +++-
 arch/arm64/kvm/mmu.c                          |  72 ++-
 arch/arm64/kvm/pkvm.c                         | 247 +++++++-
 arch/arm64/kvm/trace_pkvm.h                   |  44 ++
 18 files changed, 1036 insertions(+), 351 deletions(-)
 create mode 100644 arch/arm64/kvm/trace_pkvm.h


base-commit: f5098b6bae761e346ebcd9da7f95622c04733cff
-- 
2.55.0.508.g3f0d502094-goog