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

Marc Zyngier
2022-01-28T12:50:54Z

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);