SIGSEGV error

[mitar]

If control plane Docker container already exists, SIGSEGV is reached:

INFO[1003-05:37:50] Running: /usr/bin/docker [docker run -d --privileged --security-opt seccomp=unconfined --tmpfs /tmp --tmpfs /run --tmpfs /var/lib/docker:exec -v /lib/modules:/lib/modules:ro --hostname kind-1-control-plane --name kind-1-control-plane --label io.k8s.sigs.kind.cluster=1 --expose 6443 --publish-all --entrypoint=/usr/local/bin/entrypoint kindest/node:v1.11.3 /sbin/init] 
ERRO[1003-05:37:50] docker: Error response from daemon: Conflict. The container name "/kind-1-control-plane" is already in use by container "0e7e0562ad123ce2430b12c44c3606be4458b1189770d2bfef3ab88a97ab5282". You have to remove (or rename) that container to be able to reuse that name. 
ERRO[1003-05:37:50] See 'docker run --help'.                     
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0x5e26b9]

goroutine 1 [running]:
sigs.k8s.io/kind/pkg/cluster.(*nodeHandle).Run(0x0, 0x69654d, 0x5, 0xc4200d7638, 0x3, 0x3, 0x6978f0, 0xa)
	/usr/local/go/src/sigs.k8s.io/kind/pkg/cluster/node.go:112 +0x99
sigs.k8s.io/kind/pkg/cluster.(*nodeHandle).FixMounts(0x0, 0x14, 0x69aabb)
	/usr/local/go/src/sigs.k8s.io/kind/pkg/cluster/node.go:243 +0x96
sigs.k8s.io/kind/pkg/cluster.(*Context).provisionControlPlane(0xc420015dd0, 0xc42000d5c0, 0x14, 0xc420073620, 0x1, 0xc42000d5c0, 0x14, 0x5dc2bd)
	/usr/local/go/src/sigs.k8s.io/kind/pkg/cluster/cluster.go:158 +0xd5
sigs.k8s.io/kind/pkg/cluster.(*Context).Create(0xc420015dd0, 0xc420073620, 0x0, 0x0)
	/usr/local/go/src/sigs.k8s.io/kind/pkg/cluster/cluster.go:114 +0x13d
sigs.k8s.io/kind/cmd/kind/create.run(0xc420073530, 0xc4200cac80, 0x7f1c98, 0x0, 0x0)
	/usr/local/go/src/sigs.k8s.io/kind/cmd/kind/create/create.go:84 +0x4f6
sigs.k8s.io/kind/cmd/kind/create.NewCommand.func1(0xc4200cac80, 0x7f1c98, 0x0, 0x0)
	/usr/local/go/src/sigs.k8s.io/kind/cmd/kind/create/create.go:44 +0x52
sigs.k8s.io/kind/vendor/github.com/spf13/cobra.(*Command).execute(0xc4200cac80, 0x7f1c98, 0x0, 0x0, 0xc4200cac80, 0x7f1c98)
	/usr/local/go/src/sigs.k8s.io/kind/vendor/github.com/spf13/cobra/command.go:766 +0x2b9
sigs.k8s.io/kind/vendor/github.com/spf13/cobra.(*Command).ExecuteC(0xc4200ca280, 0xc4200caf00, 0xc4200cac80, 0xc4200ca500)
	/usr/local/go/src/sigs.k8s.io/kind/vendor/github.com/spf13/cobra/command.go:852 +0x37e
sigs.k8s.io/kind/vendor/github.com/spf13/cobra.(*Command).Execute(0xc4200ca280, 0x6a86d0, 0xc42005a0cc)
	/usr/local/go/src/sigs.k8s.io/kind/vendor/github.com/spf13/cobra/command.go:800 +0x2b
sigs.k8s.io/kind/cmd/kind.Run(0x7bade0, 0xc420056e00)
	/usr/local/go/src/sigs.k8s.io/kind/cmd/kind/kind.go:45 +0x2f
sigs.k8s.io/kind/cmd/kind.Main()
	/usr/local/go/src/sigs.k8s.io/kind/cmd/kind/kind.go:56 +0x7a
main.main()
	/usr/local/go/src/sigs.k8s.io/kind/main.go:25 +0x20

I am not familiar with Go, but SIGSEGV should never happen, no?

[BenTheElder]

it should not, this is a bad bug.

My apologies, kind is still a bit alpha, I've held off cutting any releases while I finish arranging the config and qualifying it for these kinds of bugs.

I know exactly where this bug is from that trace, I introduced it very recently (~ last day). This will be an easy fix thankfully.

This also relates to #39. We can detect existing clusters with the same name and gracefully warn, but we are not yet.

[BenTheElder]

Also relates to #23, in general the logging is somewhat atrocious at this point. I've been drafting a plan / PR to clean this up throughout the whole tool...

/kind bug
/priority important-soon
/assign

[BenTheElder]

/lifecycle active
A PR to fix this is out in #54.