Extend the NV check to pass for a GICv5 host that has
FEAT_GCIE_LEGACY. The has_gcie_v3_compat flag is only set on GICv5
hosts (that explicitly support FEAT_GCIE_LEGACY), and hence the
explicit check for a VGIC_V5 is omitted.

As of this change, vGICv3-based VMs can run with nested on a
compatible GICv5 host.

Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
---
 arch/arm64/kvm/arm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 888f7c7abf54..73ac33425927 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2315,8 +2315,9 @@ static int __init init_subsystems(void)
 	}
 
 	if (kvm_mode == KVM_MODE_NV &&
-	   !(vgic_present && kvm_vgic_global_state.type == VGIC_V3)) {
-		kvm_err("NV support requires GICv3, giving up\n");
+		!(vgic_present && (kvm_vgic_global_state.type == VGIC_V3 ||
+				   kvm_vgic_global_state.has_gcie_v3_compat))) {
+		kvm_err("NV support requires GICv3 or GICv5 with legacy support, giving up\n");
 		err = -EINVAL;
 		goto out;
 	}
-- 
2.34.1