Hi Christoffer, On 08/05/2017 13:54, Christoffer Dall wrote: > As we are about to fiddle with the io device registration mechanism > let's be a little more careful in verifying the addresses we can ealier > on to provide error messages to the user at time related to him/her > setting overlapping addresses. Above sentence would need some rewording. We still want to check a consistent > system before actually running the VM for the first time, so we make > vgic_v3_check_base available in the core vgic-v3 code as well as in the > other parts of the GICv3 code, namely the MMIO config code. > > We also return true for undefined base addresses so that the function > can be used before all base addresses are set; all callers already check > for uninitialized addresses before calling this function. > > Signed-off-by: Christoffer Dall <cdall@xxxxxxxxxx> > --- > virt/kvm/arm/vgic/vgic-v3.c | 18 ++++++++++++++---- > virt/kvm/arm/vgic/vgic.h | 1 + > 2 files changed, 15 insertions(+), 4 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c > index 12e52a0..b934e78 100644 > --- a/virt/kvm/arm/vgic/vgic-v3.c > +++ b/virt/kvm/arm/vgic/vgic-v3.c > @@ -329,19 +329,29 @@ int vgic_v3_save_pending_tables(struct kvm *kvm) > return 0; > } > > -/* check for overlapping regions and for regions crossing the end of memory */ > -static bool vgic_v3_check_base(struct kvm *kvm) > +/* > + * Check for overlapping regions and for regions crossing the end of memory > + * for base addresses which have already been set. > + */ > +bool vgic_v3_check_base(struct kvm *kvm) > { > struct vgic_dist *d = &kvm->arch.vgic; > gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE; > > redist_size *= atomic_read(&kvm->online_vcpus); > > - if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base) > + if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) && > + d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base) > return false; > - if (d->vgic_redist_base + redist_size < d->vgic_redist_base) > + > + if (!IS_VGIC_ADDR_UNDEF(d->vgic_redist_base) && > + d->vgic_redist_base + redist_size < d->vgic_redist_base) > return false; > > + if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) && > + IS_VGIC_ADDR_UNDEF(d->vgic_redist_base)) > + return true; > + > if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base) > return true; It is unclear to me if the dunction can be called if either of the address is unset? Thanks Eric > if (d->vgic_redist_base + redist_size <= d->vgic_dist_base) > diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h > index a2aeaa8..89eb935 100644 > --- a/virt/kvm/arm/vgic/vgic.h > +++ b/virt/kvm/arm/vgic/vgic.h > @@ -175,6 +175,7 @@ int vgic_v3_map_resources(struct kvm *kvm); > int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq); > int vgic_v3_save_pending_tables(struct kvm *kvm); > int vgic_register_redist_iodevs(struct kvm *kvm); > +bool vgic_v3_check_base(struct kvm *kvm); > > void vgic_v3_load(struct kvm_vcpu *vcpu); > void vgic_v3_put(struct kvm_vcpu *vcpu); >