Re: [PATCH v17 06/20] KVM: arm64: CCA: Add a new mode for supporting Realm guests

On 9/10/26 6:43 PM, Suzuki K Poulose wrote:

On 10/09/2026 06:53, Gavin Shan wrote:

quoted

Hi Suzuki,

On 9/9/26 2:22 AM, Suzuki K Poulose wrote:

quoted

Add an explicit mode to support Arm CCA guests.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
  Documentation/admin-guide/kernel-parameters.txt | 3 +++
  arch/arm64/include/asm/kvm_host.h               | 1 +
  arch/arm64/kvm/arm.c                            | 5 +++++
  3 files changed, 9 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/ Documentation/admin-guide/kernel-parameters.txt
index 68647ff4bdd24..1afe3df3b923e 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt

@@ -3256,6 +3256,9 @@ Kernel parameters

              nested: VHE-based mode with support for nested
                  virtualization. Requires at least ARMv8.4
                  hardware (with FEAT_NV2).
+            rmm: Support for running confidential guests in Realm
+                 world using RMM, as defined by Arm Confidential
+                 Compute Architecture (CCA)

I'm not sure, but 'realm' would be more appropriate name. rmm (Real Management Monitor) is
the term limited to the firmware to me. Besides, we have been using 'realm' broadly in this
series like kvm_vm_is_realm(), kvm_realm_state() and so on.

May be. But we use the "mode" of the hypervisor in question here, mostly. e.g., nvhe, vhe, protected etc. So, I went with RMM (in favor
of CCA). Does that make sense ? Also, we rely on firmware/arm_rmm for
the support. So, it kind of make sense to keep it "rmm" ?

Ok, lets keep 'rmm' unless somebody else has better suggestion.

Cheers
Suzuki

Thanks,
Gavin