KVM: arm64: Force HCR_E2H in guest context when ARM64_KVM_HVHE is set

Also make sure HCR_EL2.E2H is set when switching HCR_EL2 in guest
context.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230609162200.2024064-16-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Author: Marc Zyngier

arch/arm64/include/asm/kvm_emulate.h

@@ -74,7 +74,7 @@ static __always_inline bool vcpu_el1_is_32bit(struct kvm_vcpu *vcpu)
 static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
-	if (is_kernel_in_hyp_mode())
+	if (has_vhe() || has_hvhe())
 		vcpu->arch.hcr_el2 |= HCR_E2H;
 	if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN)) {
 		/* route synchronous external abort exceptions to EL2 */

arch/arm64/kvm/hyp/nvhe/pkvm.c

@@ -44,6 +44,9 @@ static void pvm_init_traps_aa64pfr0(struct kvm_vcpu *vcpu)
 	BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AdvSIMD),
 				PVM_ID_AA64PFR0_ALLOW));
 
+	if (has_hvhe())
+		hcr_set |= HCR_E2H;
+
 	/* Trap RAS unless all current versions are supported */
 	if (FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_RAS), feature_ids) <
 	    ID_AA64PFR0_EL1_RAS_V1P1) {