PipelineRun with pipelineSpecs panics

[chmouel]

Expected Behavior

An error or a working state

Actual Behavior

A crash :

Crash log

{"level":"info","logger":"tekton","caller":"metrics/prometheus_exporter.go:37","msg":"Created Opencensus Prometheus exporter with config: &{tekton.dev/pipeline tekton prometheus 5000000000 9090  false false  }. Start the server for Prometheus exporter."}
{"level":"info","logger":"tekton","caller":"metrics/config.go:243","msg":"Successfully updated the metrics exporter; old config: ; new config &{tekton.dev/pipeline tekton prometheus 5000000000 9090  false false  }"}
{"level":"info","logger":"tekton","caller":"sharedmain/main.go:150","msg":"Starting informers."}
{"level":"info","logger":"tekton","caller":"sharedmain/main.go:156","msg":"Starting controllers..."}
{"level":"info","logger":"tekton.pipeline-controller","caller":"controller/controller.go:280","msg":"Starting controller and workers","knative.dev/controller":"pipeline-controller"}
{"level":"info","logger":"tekton.pipeline-controller","caller":"controller/controller.go:290","msg":"Started workers","knative.dev/controller":"pipeline-controller"}
{"level":"info","logger":"tekton.pipeline-controller","caller":"pipelinerun/pipelinerun.go:114","msg":"Reconciling 2019-12-23 12:22:38.271615838 +0000 UTC m=+20.559734881","knative.dev/controller":"pipeline-controller"}
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1470ca3]
goroutine 370 [running]:

github.com/tektoncd/pipeline/pkg/reconciler/pipelinerun.(*Reconciler).reconcile(0xc00074e370, 0x1bc3840, 0xc000544c30, 0xc000c44fc0, 0x16, 0xc000c69f60)

/go/src/github.com/tektoncd/pipeline/pkg/reconciler/pipelinerun/pipelinerun.go:297 +0x963

github.com/tektoncd/pipeline/pkg/reconciler/pipelinerun.(*Reconciler).Reconcile(0xc00074e370, 0x1bc3840, 0xc000544c30, 0xc000c883c0, 0x2c, 0xc000c70340, 0x1bc3840)

/go/src/github.com/tektoncd/pipeline/pkg/reconciler/pipelinerun/pipelinerun.go:179 +0x67b

knative.dev/pkg/controller.(*Impl).processNextWorkItem(0xc0007cb180, 0xc00032c700)

/go/src/github.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:335 +0x680

knative.dev/pkg/controller.(*Impl).Run.func1(0xc000c4d0a0, 0xc0007cb180)

/go/src/github.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:285 +0x5b

created by knative.dev/pkg/controller.(*Impl).Run

/go/src/github.com/tektoncd/pipeline/vendor/knative.dev/pkg/controller/controller.go:283 +0x1ef

Steps to Reproduce the Problem

1. Import buildah task
2. Create PipelineResource for git and image output
3. Create a PipelineRun with pipelineSpec like this :

---
apiVersion: tekton.dev/v1alpha1
kind: PipelineRun
metadata:
  name: pipeline-uno
spec:
  resources:
  - name: git
    resourceRef:
      name: repo-ein
  - name: image
    resourceRef:
      name: image-dois

  pipelineSpec:
    tasks:
      - name: build-ehad
        taskRef:
          name: buildah

4. Observe controller output

Additional Info

This is using last night build from git, available here as well

[chmouel]

/kind bug

[bobcatfish]

We should fix panics ASAP! Adding this to our current milestone.