[PATCH v6 42/64] KVM: arm64: nv: Fold guest's HCR_EL2 configuration into the host's

[Marc Zyngier <maz@kernel.org>]

When entering a L2 guest (nested virt enabled, but not in hypervisor
context), we need to honor the traps the L1 guest has asked enabled.

For now, just OR the guest's HCR_EL2 into the host's. We may have to do
some filtering in the future though.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/kvm/hyp/vhe/switch.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 0e164cc8e913..5e8eafac27c6 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -78,6 +78,11 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 			if (!vcpu_el2_tge_is_set(vcpu))
 				hcr |= HCR_AT | HCR_TTLB;
 		}
+	} else if (vcpu_has_nv(vcpu)) {
+		u64 vhcr_el2 = __vcpu_sys_reg(vcpu, HCR_EL2);
+
+		vhcr_el2 &= ~HCR_GUEST_NV_FILTER_FLAGS;
+		hcr |= vhcr_el2;
 	}
 
 	___activate_traps(vcpu, hcr);
-- 
2.30.2