KVM: arm64: Fix GICv4 init when called from vgic_its_create

Commit 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization
issues") moved the vgic_supports_direct_msis() check in vgic_v4_init().
However when vgic_v4_init is called from vgic_its_create(), the has_its
field is not yet set. Hence vgic_supports_direct_msis returns false and
vgic_v4_init does nothing.

The gic/its init sequence is a bit messy, so let's be specific about the
prerequisite checks in the various call paths instead of relying on a
common wrapper.

Fixes: 3d1ad640f8c94 ("KVM: arm/arm64: Fix GICv4 ITS initialization issues")
Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

2 files changed, 6 insertions, 4 deletions

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 62310122ee78..743ca5cb05ef 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -285,9 +285,11 @@ int vgic_init(struct kvm *kvm)
         if (ret)
                 goto out;
 
-        ret = vgic_v4_init(kvm);
-        if (ret)
-                goto out;
+        if (vgic_has_its(kvm)) {
+                ret = vgic_v4_init(kvm);
+                if (ret)
+                        goto out;
+        }
 
         kvm_for_each_vcpu(i, vcpu, kvm)
                 kvm_vgic_vcpu_enable(vcpu);
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 4a37292855bc..bc4265154bac 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -118,7 +118,7 @@ int vgic_v4_init(struct kvm *kvm)
         struct kvm_vcpu *vcpu;
         int i, nr_vcpus, ret;
 
-        if (!vgic_supports_direct_msis(kvm))
+        if (!kvm_vgic_global_state.has_gicv4)
                 return 0; /* Nothing to see here... move along. */
 
         if (dist->its_vm.vpes)