[v8,00/43] arm64: Support for Arm CCA in KVM

Message

Steven Price April 16, 2025, 1:41 p.m. UTC

This series adds support for running protected VMs using KVM under the
Arm Confidential Compute Architecture (CCA).

The related guest support was merged for v6.14-rc1 so you no longer need
that separately.

There are a few changes since v7, many thanks for the review
comments. The highlights are below, and individual patches have a changelog.

 * More documentation - the new ioctls and capabilties are now all
   documented.

 * Initial patch adding "only_private"/"only_shared" to struct
   kvm_gfn_range replaced with already upstream "attr_filter".

 * Improvement in variable naming and error codes, and some improved/new
   comments. All following valuable review feedback (thanks!).

 * Drop the final WIP patch for enabling large PAGE_SIZE support. It's
   not ready for merging and I want to focus on landing the 4k support.

 * Rebased onto v6.15-rc1.

Things to note:

 * The magic numbers for capabilities and ioctls have been updated. So
   you'll need to update your VMM. See below for update kvmtool branch.

 * Patch 42 increases KVM_VCPU_MAX_FEATURES to expose the new feature.
   This also exposes the NV features (as they are currently numbered
   lower). This will resolve when Marc's NV series has landed, see [2].

 * There are some conflicts with v6.15-rc2, mostly documentation, but
   also commit 26fbdf369227 ("KVM: arm64: Don't translate FAR if
   invalid/unsafe") 'hijacks' HPFAR_EL2_NS as a valid bit. This will
   require corresponding changes to the CCA code.

The ABI to the RMM (the RMI) is based on RMM v1.0-rel0 specification[1].

This series is based on v6.15-rc1. It is also available as a git
repository:

https://gitlab.arm.com/linux-arm/linux-cca cca-host/v8

Work in progress changes for kvmtool are available from the git
repository below:

https://gitlab.arm.com/linux-arm/kvmtool-cca cca/v6

[1] https://developer.arm.com/documentation/den0137/1-0rel0/
[2] https://lore.kernel.org/r/20250408105225.4002637-17-maz%40kernel.org

Jean-Philippe Brucker (7):
  arm64: RME: Propagate number of breakpoints and watchpoints to
    userspace
  arm64: RME: Set breakpoint parameters through SET_ONE_REG
  arm64: RME: Initialize PMCR.N with number counter supported by RMM
  arm64: RME: Propagate max SVE vector length from RMM
  arm64: RME: Configure max SVE vector length for a Realm
  arm64: RME: Provide register list for unfinalized RME RECs
  arm64: RME: Provide accurate register list

Joey Gouly (2):
  arm64: RME: allow userspace to inject aborts
  arm64: RME: support RSI_HOST_CALL

Steven Price (31):
  arm64: RME: Handle Granule Protection Faults (GPFs)
  arm64: RME: Add SMC definitions for calling the RMM
  arm64: RME: Add wrappers for RMI calls
  arm64: RME: Check for RME support at KVM init
  arm64: RME: Define the user ABI
  arm64: RME: ioctls to create and configure realms
  KVM: arm64: Allow passing machine type in KVM creation
  arm64: RME: RTT tear down
  arm64: RME: Allocate/free RECs to match vCPUs
  KVM: arm64: vgic: Provide helper for number of list registers
  arm64: RME: Support for the VGIC in realms
  KVM: arm64: Support timers in realm RECs
  arm64: RME: Allow VMM to set RIPAS
  arm64: RME: Handle realm enter/exit
  arm64: RME: Handle RMI_EXIT_RIPAS_CHANGE
  KVM: arm64: Handle realm MMIO emulation
  arm64: RME: Allow populating initial contents
  arm64: RME: Runtime faulting of memory
  KVM: arm64: Handle realm VCPU load
  KVM: arm64: Validate register access for a Realm VM
  KVM: arm64: Handle Realm PSCI requests
  KVM: arm64: WARN on injected undef exceptions
  arm64: Don't expose stolen time for realm guests
  arm64: RME: Always use 4k pages for realms
  arm64: RME: Prevent Device mappings for Realms
  arm_pmu: Provide a mechanism for disabling the physical IRQ
  arm64: RME: Enable PMU support with a realm guest
  arm64: RME: Hide KVM_CAP_READONLY_MEM for realm guests
  KVM: arm64: Expose support for private memory
  KVM: arm64: Expose KVM_ARM_VCPU_REC to user space
  KVM: arm64: Allow activating realms

Suzuki K Poulose (3):
  kvm: arm64: Include kvm_emulate.h in kvm/arm_psci.h
  kvm: arm64: Don't expose debug capabilities for realm guests
  arm64: RME: Allow checking SVE on VM instance

 Documentation/virt/kvm/api.rst       |   91 +-
 arch/arm64/include/asm/kvm_emulate.h |   40 +
 arch/arm64/include/asm/kvm_host.h    |   17 +-
 arch/arm64/include/asm/kvm_rme.h     |  137 +++
 arch/arm64/include/asm/rmi_cmds.h    |  508 ++++++++
 arch/arm64/include/asm/rmi_smc.h     |  259 ++++
 arch/arm64/include/asm/virt.h        |    1 +
 arch/arm64/include/uapi/asm/kvm.h    |   49 +
 arch/arm64/kvm/Kconfig               |    1 +
 arch/arm64/kvm/Makefile              |    3 +-
 arch/arm64/kvm/arch_timer.c          |   48 +-
 arch/arm64/kvm/arm.c                 |  160 ++-
 arch/arm64/kvm/guest.c               |  104 +-
 arch/arm64/kvm/hypercalls.c          |    4 +-
 arch/arm64/kvm/inject_fault.c        |    5 +-
 arch/arm64/kvm/mmio.c                |   16 +-
 arch/arm64/kvm/mmu.c                 |  201 ++-
 arch/arm64/kvm/pmu-emul.c            |    6 +
 arch/arm64/kvm/psci.c                |   30 +
 arch/arm64/kvm/reset.c               |   23 +-
 arch/arm64/kvm/rme-exit.c            |  199 +++
 arch/arm64/kvm/rme.c                 | 1708 ++++++++++++++++++++++++++
 arch/arm64/kvm/sys_regs.c            |   49 +-
 arch/arm64/kvm/vgic/vgic-init.c      |    2 +-
 arch/arm64/kvm/vgic/vgic-v3.c        |    6 +-
 arch/arm64/kvm/vgic/vgic.c           |   54 +-
 arch/arm64/mm/fault.c                |   31 +-
 drivers/perf/arm_pmu.c               |   15 +
 include/kvm/arm_arch_timer.h         |    2 +
 include/kvm/arm_pmu.h                |    4 +
 include/kvm/arm_psci.h               |    2 +
 include/linux/perf/arm_pmu.h         |    5 +
 include/uapi/linux/kvm.h             |   29 +-
 33 files changed, 3709 insertions(+), 100 deletions(-)
 create mode 100644 arch/arm64/include/asm/kvm_rme.h
 create mode 100644 arch/arm64/include/asm/rmi_cmds.h
 create mode 100644 arch/arm64/include/asm/rmi_smc.h
 create mode 100644 arch/arm64/kvm/rme-exit.c
 create mode 100644 arch/arm64/kvm/rme.c