arm64: KVM: Inject a vSerror if detecting a bad GICV access at EL2

If, when proxying a GICV access at EL2, we detect that the guest is
doing something silly, report an EL1 SError instead ofgnoring the
access.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

1 files changed, 16 insertions, 5 deletions

diff --git a/virt/kvm/arm/hyp/vgic-v2-sr.c b/virt/kvm/arm/hyp/vgic-v2-sr.c
index a052f2056cc0..c8aeb7b91ec8 100644
--- a/virt/kvm/arm/hyp/vgic-v2-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v2-sr.c
@@ -170,7 +170,18 @@ void __hyp_text __vgic_v2_restore_state(struct kvm_vcpu *vcpu)
 }
 
 #ifdef CONFIG_ARM64
-bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
+/*
+ * __vgic_v2_perform_cpuif_access -- perform a GICV access on behalf of the
+ *                                   guest.
+ *
+ * @vcpu: the offending vcpu
+ *
+ * Returns:
+ *  1: GICV access successfully performed
+ *  0: Not a GICV access
+ * -1: Illegal GICV access
+ */
+int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
 {
         struct kvm *kvm = kern_hyp_va(vcpu->kvm);
         struct vgic_dist *vgic = &kvm->arch.vgic;
@@ -185,15 +196,15 @@ bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
         /* If not for GICV, move on */
         if (fault_ipa <  vgic->vgic_cpu_base ||
             fault_ipa >= (vgic->vgic_cpu_base + KVM_VGIC_V2_CPU_SIZE))
-                return false;
+                return 0;
 
         /* Reject anything but a 32bit access */
         if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
-                return false;
+                return -1;
 
         /* Not aligned? Don't bother */
         if (fault_ipa & 3)
-                return false;
+                return -1;
 
         rd = kvm_vcpu_dabt_get_rd(vcpu);
         addr  = kern_hyp_va((kern_hyp_va(&kvm_vgic_global_state))->vcpu_base_va);
@@ -210,6 +221,6 @@ bool __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
                                                                sizeof(u32)));
         }
 
-        return true;
+        return 1;
 }
 #endif