Subject: [RFC PATCH v4 00/16] coco/TSM: Implement host-side support for Arm CCA TDISP setup

From: "Aneesh Kumar K.V (Arm)" <[email-masked]>
Date: Mon, 27 Apr 2026 14:23:28 +0530

This patch series implements the host-side changes needed for end-to-end
Arm CCA TDISP setup. It adds the RMI/RHI plumbing required to create and
manage Realm vdev objects, service device-attestation object requests, and
complete the KVM/RMM flows needed for device run-time transitions.

The series is based on the RMM 2.0bet1 specification [1] and the
RHI v1.0 BET1 specification [5].

At a high level, the series adds support for:
- host-side vdev communication and lifecycle management
- host handling of RHI DA object read/size requests
- host-side fetching and caching of interface reports and measurements
- KVM handling of vdev request/complete exits
- KVM handling of map/validation exits and teardown on granule destroy
- vdev transition to TDISP RUN state
- enabling DA in Realm create parameters

The series builds upon the TSM framework patches posted at [2] and depends on
the KVM CCA patchset [3]. A git repository containing all related changes is
available at [4]. kvmtool repo is at [6]

Previous posting:
Changes from v3:
https://lore.kernel.org/all/[email-masked]
* updated the patches to follow the RMM 2.0bet1 specification
* moved vdev request-exit handling to the last patch in the series. This is
  expected to be dropped once the corresponding spec update lands
* dropped the vdev and pdev arguments from rmi_rtt_dev_validate(). The spec
  update for that change is still pending. The validation call is now made
  from the REC enter path
* added a response field to KVM_EXIT_ARM64_TIO so the VMM can pass the ioctl
  return status back to the exit handler
* dropped vcpu_fd from arm64_vdev_device_memmap_guest_req. Once vdev request
  handling is removed from the series, the ioctl path will no longer need
  vcpu_fd
* reworked the host-side vdev lifecycle to better match the RMM 2.0bet1 flow,
* updated the vdev flows to match the revised interfaces: populate MMIO BAR
  ranges in rmi_vdev_create(), rename the interface-report and measurement
  update commands, and drop vcpu_fd from the guest MMIO map request path

Changes from v1:
* rebase to latest kernel and core TSM changes
* address review feedback

rfc-v1: https://lore.kernel.org/all/[email-masked]
There is no rfc-v2 posting. This series is marked rfc-v3 to stay aligned
with the rest of the CCA patchsets that are being posted as v3.

[1] https://developer.arm.com/documentation/den0137/2-0bet1/
[2] https://lore.kernel.org/all/[email-masked]
[3] https://lore.kernel.org/all/[email-masked]
[4] https://gitlab.arm.com/linux-arm/linux-cca.git cca/topics/cca-tdisp-upstream-rfc-v4
[5] https://developer.arm.com/documentation/den0148/latest/
[6] https://gitlab.arm.com/linux-arm/kvmtool-cca.git cca/topics/cca-tdisp-upstream-rfc-v4

Cc: Alexey Kardashevskiy <[email-masked]>
Cc: Catalin Marinas <[email-masked]>
Cc: Dan Williams <[email-masked]>
Cc: Jason Gunthorpe <[email-masked]>
Cc: Joerg Roedel <[email-masked]>
Cc: Jonathan Cameron <[email-masked]>
Cc: Marc Zyngier <[email-masked]>
Cc: Nicolin Chen <[email-masked]>
Cc: Pranjal Shrivastava <[email-masked]>
Cc: Robin Murphy <[email-masked]>
Cc: Samuel Ortiz <[email-masked]>
Cc: Steven Price <[email-masked]>
Cc: Suzuki K Poulose <[email-masked]>
Cc: Will Deacon <[email-masked]>
Cc: Xu Yilun <[email-masked]>

Aneesh Kumar K.V (Arm) (16):
  iommu/arm-smmu-v3: Discover RME support and realm IRQ topology
  iommu/arm-smmu-v3: Save the programmed MSI message in msi_desc
  iommu/arm-smmu-v3: Add initial pSMMU realm viommu plumbing
  iommu/arm-smmu-v3: Track realm pSMMU users with refcount_t
  coco: host: arm64: Add support for virtual device communication
  coco: host: arm64: Add support for RMM vdev objects
  coco: host: arm64: Add pdev stream key refresh and purge helpers
  coco: host: arm64: Add helpers to unlock and destroy RMM vdev
  coco: host: arm64: Add support for da object read RHI handling
  coco: host: arm64: Add helper for cached object fetches
  coco: host: arm64: Fetch interface report via RMI
  coco: host: arm64: Fetch device measurements via RMI
  coco: host: KVM: arm64: Handle vdev validate-mapping exits
  KVM: arm64: Unmap device mappings when a private granule is destroyed
  coco: host: arm64: Transition vdevs to TDISP RUN state
  KVM: arm64: CCA: enable DA in realm create parameters

 Documentation/virt/kvm/api.rst                |  20 +
 arch/arm64/include/asm/kvm_rmi.h              |   4 +
 arch/arm64/include/asm/rmi_cmds.h             | 193 ++++++
 arch/arm64/include/asm/rmi_smc.h              |  98 ++-
 arch/arm64/include/uapi/asm/rmi-da.h          |  47 ++
 arch/arm64/kernel/rmi.c                       |  51 ++
 arch/arm64/kvm/rmi-exit.c                     |  37 ++
 arch/arm64/kvm/rmi.c                          | 279 ++++++++-
 drivers/iommu/arm/arm-smmu-v3/Makefile        |   2 +-
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     |   7 +
 .../iommu/arm/arm-smmu-v3/arm-smmu-v3-realm.c | 297 +++++++++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   |  86 ++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   |  16 +
 drivers/virt/coco/arm-cca-host/arm-cca.c      | 188 +++++-
 drivers/virt/coco/arm-cca-host/rmi-da.c       | 569 +++++++++++++++++-
 drivers/virt/coco/arm-cca-host/rmi-da.h       |  40 ++
 include/uapi/linux/iommufd.h                  |   1 +
 include/uapi/linux/kvm.h                      |  11 +
 18 files changed, 1929 insertions(+), 17 deletions(-)
 create mode 100644 arch/arm64/include/uapi/asm/rmi-da.h
 create mode 100644 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-realm.c

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2.43.0