KVM: arm64: implement dummy guest HVC handler at HYP
Prepare the hypervisor for relaying pKVM TRNG interface calls directly
to secure world, by introducing a hook for HVC calls issued from AArch64
state. The hook currently does nothing, so all HVCs intercepted in this
way will still cause an exit back to the host.
Signed-off-by: Ard Biesheuvel <ardb@google.com>
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 0397606c..ff8e173 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -401,6 +401,11 @@
return false;
}
+static bool kvm_hyp_handle_hvc64(struct kvm_vcpu *vcpu, u64 *exit_code)
+{
+ return false;
+}
+
typedef bool (*exit_handler_fn)(struct kvm_vcpu *, u64 *);
static const exit_handler_fn *kvm_get_exit_handler_array(void);
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 876268c..7e4a6ac 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -168,6 +168,7 @@
[ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low,
[ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low,
[ESR_ELx_EC_PAC] = kvm_hyp_handle_ptrauth,
+ [ESR_ELx_EC_HVC64] = kvm_hyp_handle_hvc64,
};
static const exit_handler_fn *kvm_get_exit_handler_array(void)
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index d6640f3..8218b00 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -106,6 +106,7 @@
[ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low,
[ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low,
[ESR_ELx_EC_PAC] = kvm_hyp_handle_ptrauth,
+ [ESR_ELx_EC_HVC64] = kvm_hyp_handle_hvc64,
};
static const exit_handler_fn *kvm_get_exit_handler_array(void)
