diff --git a/pkg/compute/models/hosts.go b/pkg/compute/models/hosts.go
index a4498b9dc6..2c22cc50df 100644
--- a/pkg/compute/models/hosts.go
+++ b/pkg/compute/models/hosts.go
@@ -4274,9 +4274,14 @@ func (hh *SHost) PerformReserveCpus(
 		return nil, err
 	}
 
-	if !sets.NewInt(allCores...).HasAll(cs.ToSlice()...) {
+	hSets := sets.NewInt(allCores...)
+	cSlice := cs.ToSlice()
+	if !hSets.HasAll(cSlice...) {
 		return nil, httperrors.NewInputParameterError("Host cores not contains input %v", input.Cpus)
 	}
+	if hSets.Len() == len(cSlice) {
+		return nil, httperrors.NewInputParameterError("Can't reserve host all cpus")
+	}
 
 	if input.Mems != "" {
 		mems, err := cpuset.Parse(input.Mems)