istio: helm chart for release version install failed for missing named template in _helpers.tpl partial files

env:

centos: 7.2
istio version: 0.6.0
kubenetes version: v1.9.1

install command:

helm install --debug --dry-run --name istio --namespace istio-system istio-0.6.0/install/kubernetes/helm/istio

problem:

[debug] Created tunnel using local port: '60884'

[debug] SERVER: "127.0.0.1:60884"

[debug] Original chart version: ""
[debug] Key="/var/lib/helm/key.pem", Cert="/var/lib/helm/cert.pem", CA="/var/lib/helm/ca.pem"

[debug] CHART PATH: /root/istio-0.6.0/install/kubernetes/helm/istio

Error: render error in "istio/charts/pilot/templates/serviceaccount.yaml": template: istio/charts/pilot/templates/serviceaccount.yaml:5:20: executing "istio/charts/pilot/templates/serviceaccount.yaml" at <{{template "pilot.se...>: template "pilot.serviceAccountName" not defined

While install from source code, it’s all right:

helm install --debug --dry-run --name istio --namespace istio-system istio/install/kubernetes/helm/istio
[debug] Created tunnel using local port: '46249'

[debug] SERVER: "127.0.0.1:46249"

[debug] Original chart version: ""
[debug] Key="/var/lib/helm/key.pem", Cert="/var/lib/helm/cert.pem", CA="/var/lib/helm/ca.pem"

[debug] CHART PATH: /root/istio/install/kubernetes/helm/istio

NAME:   istio
REVISION: 1
RELEASED: Fri Mar  2 02:40:42 2018
CHART: istio-0.6.0
USER-SUPPLIED VALUES:
{}

COMPUTED VALUES:
...