[PATCH v3 0/2] KVM: arm64: Support FF-A direct messaging interfaces

Per Larsen via B4 Relay posted 2 patches 1 week, 6 days ago
arch/arm64/kvm/hyp/nvhe/ffa.c | 33 +++++++++++++++++++++++++++++++++
include/linux/arm_ffa.h       |  3 +++
2 files changed, 36 insertions(+)
[PATCH v3 0/2] KVM: arm64: Support FF-A direct messaging interfaces
Posted by Per Larsen via B4 Relay 1 week, 6 days ago
Support FFA_MSG_SEND_DIRECT_REQ unconditionally.
Support FFA_MSG_SEND_DIRECT_REQ2 if hypervisor negotiated version 1.2+.

Framework messages (FF-A control plane) are filtered out. For
FFA_MSG_SEND_DIRECT_REQ, we look at flags in w2. Messages using the REQ2
interface are always partition messages.

The second patch was part of a previous patch set [0] but was dropped
since the use case was unclear. A clear use case has now appeared: use
TPM device with CRB over FF-A when kernel boots with pkvm [1].

Tested by booting Android under QEMU.

Best Regards,
Per

[0]: https://lore.kernel.org/all/20250730-virtio-msg-ffa-v9-0-7f1b55c8d149@google.com/
[1]: https://lore.kernel.org/all/20251027191729.1704744-1-yeoreum.yun@arm.com/
 

Signed-off-by: Per Larsen <perlarsen@google.com>
---
Changes in v3:
- Filter out framework messages as suggested by Will Deacon. Update cover letter accordingly.
- Update trailers: Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
- Link to v2: https://lore.kernel.org/r/20251030-host-direct-messages-v2-0-9f27cef36730@google.com

Changes in v2:
- 1/2: Drop support for FFA_ID_GET interface in host handler.
- Link to v1: https://lore.kernel.org/r/20251030-host-direct-messages-v1-0-463e57871c8f@google.com

---
Per Larsen (1):
      KVM: arm64: Support FFA_MSG_SEND_DIRECT_REQ2 in host handler

Sebastian Ene (1):
      KVM: arm64: Support FFA_MSG_SEND_DIRECT_REQ in host handler

 arch/arm64/kvm/hyp/nvhe/ffa.c | 33 +++++++++++++++++++++++++++++++++
 include/linux/arm_ffa.h       |  3 +++
 2 files changed, 36 insertions(+)
---
base-commit: e7c375b181600caf135cfd03eadbc45eb530f2cb
change-id: 20251029-host-direct-messages-5201d7f55abd

Best regards,
-- 
Per Larsen <perlarsen@google.com>