Merge pull request #9480 from adongy/master

aws: retry fetching blockdevicemapping if empty

builder/amazon/common/step_run_spot_instance.go

@@ -324,6 +324,11 @@ func (s *StepRunSpotInstance) Run(ctx context.Context, state multistep.StateBag)
 		describeOutput, err = ec2conn.DescribeInstances(&ec2.DescribeInstancesInput{
 			InstanceIds: []*string{aws.String(instanceId)},
 		})
+		if len(describeOutput.Reservations) > 0 && len(describeOutput.Reservations[0].Instances) > 0 {
+			if len(s.LaunchMappings.BuildEC2BlockDeviceMappings()) > 0 && len(describeOutput.Reservations[0].Instances[0].BlockDeviceMappings) == 0 {
+				return fmt.Errorf("Instance has no block devices")
+			}
+		}
 		return err
 	})
 	if err != nil || len(describeOutput.Reservations) == 0 || len(describeOutput.Reservations[0].Instances) == 0 {