* kvm-arm64/shadow-mmu:
  : Shadow stage-2 MMU support for NV, courtesy of Marc Zyngier
  :
  : Initial implementation of shadow stage-2 page tables to support a guest
  : hypervisor. In the author's words:
  :
  :   So here's the 10000m (approximately 30000ft for those of you stuck
  :   with the wrong units) view of what this is doing:
  :
  :     - for each {VMID,VTTBR,VTCR} tuple the guest uses, we use a
  :       separate shadow s2_mmu context. This context has its own "real"
  :       VMID and a set of page tables that are the combination of the
  :       guest's S2 and the host S2, built dynamically one fault at a time.
  :
  :     - these shadow S2 contexts are ephemeral, and behave exactly as
  :       TLBs. For all intent and purposes, they *are* TLBs, and we discard
  :       them pretty often.
  :
  :     - TLB invalidation takes three possible paths:
  :
  :       * either this is an EL2 S1 invalidation, and we directly emulate
  :         it as early as possible
  :
  :       * or this is an EL1 S1 invalidation, and we need to apply it to
  :         the shadow S2s (plural!) that match the VMID set by the L1 guest
  :
  :       * or finally, this is affecting S2, and we need to teardown the
  :         corresponding part of the shadow S2s, which invalidates the TLBs
  KVM: arm64: nv: Truely enable nXS TLBI operations
  KVM: arm64: nv: Add handling of NXS-flavoured TLBI operations
  KVM: arm64: nv: Add handling of range-based TLBI operations
  KVM: arm64: nv: Add handling of outer-shareable TLBI operations
  KVM: arm64: nv: Invalidate TLBs based on shadow S2 TTL-like information
  KVM: arm64: nv: Tag shadow S2 entries with guest's leaf S2 level
  KVM: arm64: nv: Handle FEAT_TTL hinted TLB operations
  KVM: arm64: nv: Handle TLBI IPAS2E1{,IS} operations
  KVM: arm64: nv: Handle TLBI ALLE1{,IS} operations
  KVM: arm64: nv: Handle TLBI VMALLS12E1{,IS} operations
  KVM: arm64: nv: Handle TLB invalidation targeting L2 stage-1
  KVM: arm64: nv: Handle EL2 Stage-1 TLB invalidation
  KVM: arm64: nv: Add Stage-1 EL2 invalidation primitives
  KVM: arm64: nv: Unmap/flush shadow stage 2 page tables
  KVM: arm64: nv: Handle shadow stage 2 page faults
  KVM: arm64: nv: Implement nested Stage-2 page table walk logic
  KVM: arm64: nv: Support multiple nested Stage-2 mmu structures
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>