From: Eric Auger <eric.auger@xxxxxxxxxx> Saving/restoring an unmapped collection is a valid scenario. For example this happens if a MAPTI command was sent, featuring an unmapped collection. At the moment the CTE fails to be restored. Only compare against the number of online vcpus if the rdist base is set. Fixes: ea1ad53e1e31a ("KVM: arm64: vgic-its: Collection table save/restore") Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Reviewed-by: Zenghui Yu <yuzenghui@xxxxxxxxxx> Link: https://lore.kernel.org/r/20191213094237.19627-1-eric.auger@xxxxxxxxxx --- virt/kvm/arm/vgic/vgic-its.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 98c7360d9fb7..17920d1b350a 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -2475,7 +2475,8 @@ static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz) target_addr = (u32)(val >> KVM_ITS_CTE_RDBASE_SHIFT); coll_id = val & KVM_ITS_CTE_ICID_MASK; - if (target_addr >= atomic_read(&kvm->online_vcpus)) + if (target_addr != COLLECTION_NOT_MAPPED && + target_addr >= atomic_read(&kvm->online_vcpus)) return -EINVAL; collection = find_collection(its, coll_id); -- 2.20.1