Re: [PATCH v22 16/23] KVM: arm64: CCA: Add VCPU load/put for Realms

From: Suzuki K Poulose

Date: Tue Oct 06 2026 - 01:09:42 EST



Hi Gavin

On 06/10/2026 04:16, Gavin Shan wrote:
On 10/5/26 7:07 PM, Suzuki K Poulose wrote:
RMM controls the VCPU settings and most are hidden from the KVM, except
for the VGIC and timer bits.

A later patch would add syncing the VCPU state into the Realm REC related
SMC parameters.

This is what you are looking for ^^^


Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
  arch/arm64/kvm/arm.c | 18 ++++++++++++++++++
  1 file changed, 18 insertions(+)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 6c81fec35ecec..294cea4cc8271 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -802,6 +802,13 @@ static void pkvm_vcpu_load(struct kvm_vcpu *vcpu)
                &vcpu->arch.vgic_cpu.vgic_v3);
  }
+static void realm_vcpu_load(struct kvm_vcpu *vcpu)
+{
+    kvm_timer_vcpu_load(vcpu);
+    kvm_vgic_load(vcpu);
+    vcpu_set_wfx_traps(vcpu);

Why we need to call vcpu_set_wfx_traps(), which updates 'vcpu- >arch.hcr_el2'? I don't
see how 'vcpu->arch.hcr_el2' is affects realm in RMM. Could you please explain in the
commit log.

See above.


Cheers
Suzuki


+}
+
  void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
  {
      vcpu->cpu = cpu;
@@ -854,6 +861,12 @@ static void pkvm_vcpu_put(struct kvm_vcpu *vcpu)
      kvm_vcpu_pmu_restore_host(vcpu);
  }
+static void realm_vcpu_put(struct kvm_vcpu *vcpu)
+{
+    kvm_timer_vcpu_put(vcpu);
+    kvm_vgic_put(vcpu);
+}
+
  void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
  {
      vcpu->arch.vcpu_ops->vcpu_put(vcpu);
@@ -2213,6 +2226,11 @@ static const struct kvm_vcpu_ops pkvm_vcpu_ops = {
      .vcpu_put = pkvm_vcpu_put,
  };
+static const struct kvm_vcpu_ops realm_vcpu_ops = {
+    .vcpu_load = realm_vcpu_load,
+    .vcpu_put = realm_vcpu_put,
+};
+
  #define KVM_VCPU_OPS(flavor, ops)        \
      [(flavor)] = &(ops)

Thanks,
Gavin