KVM: arm64: vgic-v4: Initialize GICv4.1 even in the absence of a virtual ITS

KVM now expects to be able to use HW-accelerated delivery of vSGIs
as soon as the guest has enabled thm. Unfortunately, we only
initialize the GICv4 context if we have a virtual ITS exposed to
the guest.

Fix it by always initializing the GICv4.1 context if it is
available on the host.

Fixes: 2291ff2f2a56 ("KVM: arm64: GICv4.1: Plumb SGI implementation selection in the distributor")
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 30dbec9fe0b4adcc849f14c4e36a7c77ffd96be2..32e32d67a127f0e7a3b59a4e5b36d1c9c124d7b9 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -294,8 +294,15 @@ int vgic_init(struct kvm *kvm)
                }
        }
 
-       if (vgic_has_its(kvm)) {
+       if (vgic_has_its(kvm))
                vgic_lpi_translation_cache_init(kvm);
+
+       /*
+        * If we have GICv4.1 enabled, unconditionnaly request enable the
+        * v4 support so that we get HW-accelerated vSGIs. Otherwise, only
+        * enable it if we present a virtual ITS to the guest.
+        */
+       if (vgic_supports_direct_msis(kvm)) {
                ret = vgic_v4_init(kvm);
                if (ret)
                        goto out;

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 416613f2400c5978286411816991c95c8b5d4c20..89a14ec8b33bb2009786d921759868943a152e24 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -50,7 +50,8 @@ bool vgic_has_its(struct kvm *kvm)
 
 bool vgic_supports_direct_msis(struct kvm *kvm)
 {
-       return kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm);
+       return (kvm_vgic_global_state.has_gicv4_1 ||
+               (kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm)));
 }
 
 /*