[RFC PATCH 0/5] Add TDX intra host migration support

[Sagi Shahar]

This patchset adds support for TDX intra host migration using the same
API which was added for SEV intra host migration here:
https://lore.kernel.org/all/20211021174303.385706-1-pgonda@xxxxxxxxxx/

This patchset relies on the latest TDX patches from Intel:
- fd-based approach for supporing KVM v10 and
  https://lore.kernel.org/lkml/20221202061347.1070246-1-chao.p.peng@xxxxxxxxxxxxxxx/
- TDX host kernel support v10
  https://lore.kernel.org/lkml/cover.1678111292.git.kai.huang@xxxxxxxxx/
- KVM TDX basic feature support v13
  https://lore.kernel.org/cover.1678643051.git.isaku.yamahata@xxxxxxxxx

The tree can be found at https://github.com/googleprodkernel/linux-cc/tree/copyless
and is based on Intel's tdx tree at https://github.com/intel/tdx/tree/kvm-upstream

In the TDX case, we need to transfer the VM state from multiple sources:

 * HKID and encrypted VM state is transfered between the kvm_tdx
   objects.
 * Encrypted and runtime state is transfered between the vcpu_tdx
   objects.
 * The EPT table backing TD's private memory is transfered at the
   kvm-mmu level. This is needed since the secure EPT table managed by
   the TD module remains the same after the migration so moving the
   current private EPT table eliminates the need to rebuild the private
   EPT table to match the secure EPT table on the destination.
 * Information regarding the current shared/private memory is trasfered
   using the mem_attr_array stored at the kvm object.
 * Additional information derived from shared/private memory state is
   trasfered at the memslot level.

Tested with selftests locally. I will attach the self test in the next
version after we send the new TDX selftest framework patches based on
KVM TDX basic feature support v13.

Sagi Shahar (5):
  KVM: Split tdp_mmu_pages to private and shared lists
  KVM: SEV: Refactor common code out of sev_vm_move_enc_context_from
  KVM: TDX: Add base implementation for tdx_vm_move_enc_context_from
  KVM: TDX: Implement moving private pages between 2 TDs
  KVM: TDX: Add core logic for TDX intra-host migration

 arch/x86/include/asm/kvm_host.h |   5 +-
 arch/x86/kvm/mmu.h              |   2 +
 arch/x86/kvm/mmu/mmu.c          |  60 ++++++++
 arch/x86/kvm/mmu/tdp_mmu.c      |  88 +++++++++++-
 arch/x86/kvm/mmu/tdp_mmu.h      |   3 +
 arch/x86/kvm/svm/sev.c          | 175 +++--------------------
 arch/x86/kvm/vmx/main.c         |  10 ++
 arch/x86/kvm/vmx/tdx.c          | 245 ++++++++++++++++++++++++++++++++
 arch/x86/kvm/vmx/tdx.h          |   2 +
 arch/x86/kvm/vmx/x86_ops.h      |   5 +
 arch/x86/kvm/x86.c              | 166 ++++++++++++++++++++++
 arch/x86/kvm/x86.h              |  16 +++
 12 files changed, 613 insertions(+), 164 deletions(-)

-- 
2.40.0.348.gf938b09366-goog