diff mbox series

[RFC,4/7] KVM: arm64: Forward guest CPU state to TEE mediator on SMC trap

Message ID 20250401170527.344092-5-yuvraj.kernel@gmail.com (mailing list archive)
State New
Headers show
Series KVM: optee: Introduce OP-TEE Mediator for exposing secure world to KVM guests | expand

Commit Message

Yuvraj Sakshith April 1, 2025, 5:05 p.m. UTC 
When guest makes an SMC, the call is denied by the hypervisor
and not handled (ignored). In the presence of the TEE Mediator
module, the SMC from guest is forwarded with it's vCPU register
state through tee_mediator_forward_request().

Signed-off-by: Yuvraj Sakshith <yuvraj.kernel@gmail.com>
---
 arch/arm64/kvm/hypercalls.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
index 569941eeb3fe..cb34bb87188c 100644
--- a/arch/arm64/kvm/hypercalls.c
+++ b/arch/arm64/kvm/hypercalls.c
@@ -3,6 +3,7 @@ 
 
 #include <linux/arm-smccc.h>
 #include <linux/kvm_host.h>
+#include <linux/tee_mediator.h>
 
 #include <asm/kvm_emulate.h>
 
@@ -90,7 +91,10 @@  static bool kvm_smccc_default_allowed(u32 func_id)
 		 */
 		if (func_id >= KVM_PSCI_FN(0) && func_id <= KVM_PSCI_FN(3))
 			return true;
-
+#ifdef CONFIG_TEE_MEDIATOR
+		if (ARM_SMCCC_IS_OWNER_TRUSTED_APP(func_id) || ARM_SMCCC_IS_OWNER_TRUSTED_OS(func_id))
+			return true;
+#endif
 		return false;
 	}
 }
@@ -284,7 +288,14 @@  int kvm_smccc_call_handler(struct kvm_vcpu *vcpu)
 		WARN_RATELIMIT(1, "Unhandled SMCCC filter action: %d\n", action);
 		goto out;
 	}
-
+#ifdef CONFIG_TEE_MEDIATOR
+	if (ARM_SMCCC_IS_OWNER_TRUSTED_APP(func_id) || ARM_SMCCC_IS_OWNER_TRUSTED_OS(func_id)) {
+		if (tee_mediator_is_active()) {
+			tee_mediator_forward_request(vcpu);
+			return 1;
+		}
+	}
+#endif
 	switch (func_id) {
 	case ARM_SMCCC_VERSION_FUNC_ID:
 		val[0] = ARM_SMCCC_VERSION_1_1;