KVM: arm64: Fix resetting SVE trap values on reset for hVHE

Ensure that SVE traps are disabled for hVHE, if the FPSIMD state
isn't owned by the guest, when getting the reset value for the
architectural feature control register.

Fixes: 75c76ab5 ("KVM: arm64: Rework CPTR_EL2 programming for HVHE configuration")
Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230724123829.2929609-8-tabba@google.comSigned-off-by: Oliver Upton <oliver.upton@linux.dev>

arch/arm64/include/asm/kvm_emulate.h

@@ -588,6 +588,10 @@ static __always_inline u64 kvm_get_reset_cptr_el2(struct kvm_vcpu *vcpu)
 		       CPACR_EL1_ZEN_EL1EN);
 	} else if (has_hvhe()) {
 		val = (CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN);
+
+		if (!vcpu_has_sve(vcpu) ||
+		    (vcpu->arch.fp_state != FP_STATE_GUEST_OWNED))
+			val |= CPACR_EL1_ZEN_EL1EN | CPACR_EL1_ZEN_EL0EN;
 	} else {
 		val = CPTR_NVHE_EL2_RES1;