[PATCH v1 0/8] KVM: arm64: Reserve pKVM VM handle during initial VM setup

[Fuad Tabba <tabba@google.com>]

All VMs in pKVM identified by their handle, a unique per-VM ID. This
handle is shared between the host kernel and the hypvervisor, and used
to track the VM across both.

In pKVM, this handle is allocated when the VM is initialized at the
hypervisor, which is on the first vCPU run. However, the host starts
initializing the VM and setting up its data structures earlier. MMU
notifiers for the VMs are also registered before VM identification at
the hypervisor, which rely on the handle to identify the VM [1].

Additionally, in the future, the host needs to communicate with
TrustZone about the before the VM first run. Therefore, move handle
creation to when the VM is first initialized at the host.

This patch series is divided into two parts:

- Patches 1-4: Renaming, refactoring, and tidying up to lay the
  groundwork for moving handle initialization and to fix existing
  issues.
- Patches 5-8: Decouple handle creation from VM initialization at the
  hypervisor and move the handle creation to VM initialization at the
  host.

Based on Linux 6.16.

Cheers,
/fuad

[1] https://lore.kernel.org/all/20250303214947.GA30619@willie-the-truck/

Fuad Tabba (8):
  KVM: arm64: Rename pkvm.enabled to pkvm.is_protected
  KVM: arm64: Rename 'host_kvm' to 'kvm' in pKVM host code
  KVM: arm64: Clarify comments to distinguish pKVM mode from protected
    VMs
  KVM: arm64: Decouple hyp VM creation state from its handle
  KVM: arm64: Separate allocation and insertion of pKVM VM table entries
  KVM: arm64: Consolidate pKVM hypervisor VM initialization logic
  KVM: arm64: Introduce separate hypercalls for pKVM VM reservation and
    initialization
  KVM: arm64: Reserve pKVM handle during pkvm_init_host_vm()

 arch/arm64/include/asm/kvm_asm.h       |   2 +
 arch/arm64/include/asm/kvm_host.h      |   5 +-
 arch/arm64/include/asm/kvm_pkvm.h      |   1 +
 arch/arm64/kvm/arm.c                   |  12 +-
 arch/arm64/kvm/hyp/include/nvhe/pkvm.h |   4 +-
 arch/arm64/kvm/hyp/nvhe/hyp-main.c     |  14 ++
 arch/arm64/kvm/hyp/nvhe/pkvm.c         | 177 +++++++++++++++++++------
 arch/arm64/kvm/pkvm.c                  |  76 +++++++----
 8 files changed, 217 insertions(+), 74 deletions(-)


base-commit: 038d61fd642278bab63ee8ef722c50d10ab01e8f
-- 
2.50.1.487.gc89ff58d15-goog