arm/arm64: KVM: make the maximum number of vCPUs a per-VM value
Currently the maximum number of vCPUs supported is a global value
limited by the used GIC model. GICv3 will lift this limit, but we
still need to observe it for guests using GICv2.
So the maximum number of vCPUs is per-VM value, depending on the
GIC model the guest uses.
Store and check the value in struct kvm_arch, but keep it down to
8 for now.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 3a51ffca..6fbfa5f 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -132,6 +132,9 @@
/* Mark the initial VMID generation invalid */
kvm->arch.vmid_gen = 0;
+ /* The maximum number of VCPUs is limited by the host's GIC model */
+ kvm->arch.max_vcpus = kvm_vgic_get_max_vcpus();
+
return ret;
out_free_stage2_pgd:
kvm_free_stage2_pgd(kvm);
@@ -218,6 +221,11 @@
goto out;
}
+ if (id >= kvm->arch.max_vcpus) {
+ err = -EINVAL;
+ goto out;
+ }
+
vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
if (!vcpu) {
err = -ENOMEM;