arm/arm64: KVM: vgic: handle out-of-range MMIO accesses
Now that we can (almost) dynamically size the number of interrupts,
we're facing an interesting issue:
We have to evaluate at runtime whether or not an access hits a valid
register, based on the sizing of this particular instance of the
distributor. Furthermore, the GIC spec says that accessing a reserved
register is RAZ/WI.
For this, add a new field to our range structure, indicating the number
of bits a single interrupts uses. That allows us to find out whether or
not the access is in range.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 3b73d78..2767f93 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -32,6 +32,7 @@
#define VGIC_V2_MAX_LRS (1 << 6)
#define VGIC_V3_MAX_LRS 16
+#define VGIC_MAX_IRQS 1024
/* Sanity checks... */
#if (KVM_MAX_VCPUS > 8)
@@ -42,7 +43,7 @@
#error "VGIC_NR_IRQS must be a multiple of 32"
#endif
-#if (VGIC_NR_IRQS > 1024)
+#if (VGIC_NR_IRQS > VGIC_MAX_IRQS)
#error "VGIC_NR_IRQS must be <= 1024"
#endif