Arvados

Version 1.3.1.20190318151156-1 running on c97qk:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x10 pc=0x858bd9]
goroutine 68 [running]:
git.curoverse.com/arvados.git/lib/cloud/azure.(*azureInstance).Address(0xc420413d60, 0xc420296d10, 0xad)
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/cloud/azure/azure.go:648 +0x9
git.curoverse.com/arvados.git/lib/dispatchcloud/worker.(*Pool).updateWorker(0xc42019d340, 0xb5e2e0, 0xc4204fb600, 0xc4202b70b0, 0xe, 0xc4202b70b0, 0xe, 0x1, 0xd59f8000, 0xba43b7400, ...)
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/dispatchcloud/worker/pool.go:366 +0x3a4
git.curoverse.com/arvados.git/lib/dispatchcloud/worker.(*Pool).sync(0xc42019d340, 0xbf1c1ec2f96cd79c, 0x1266d687d61, 0xe36da0, 0xc42006b0c0, 0x4, 0x4)
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/dispatchcloud/worker/pool.go:770 +0x452
git.curoverse.com/arvados.git/lib/dispatchcloud/worker.(*Pool).getInstancesAndSync(0xc42019d340, 0x0, 0x0)
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/dispatchcloud/worker/pool.go:749 +0x27e
git.curoverse.com/arvados.git/lib/dispatchcloud/worker.(*Pool).runSync(0xc42019d340)
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/dispatchcloud/worker/pool.go:675 +0x12f
created by git.curoverse.com/arvados.git/lib/dispatchcloud/worker.NewPool.func1
        /tmp/tmp.AW7MSQbSFH/src/git.curoverse.com/arvados.git/lib/dispatchcloud/worker/pool.go:116 +0xb9

Suspect it's just that #14844 didn't account for ai.nic being nil on line 648 here:

func (ai *azureInstance) Address() string {
        if ai.nic.IPConfigurations != nil &&

It seems like ai.nic becomes nil in Instances() if az.vmClient.listComplete() refers to a nic that didn't show up in az.manageNics() (interfaces[*(*result.Value().NetworkProfile.NetworkInterfaces)[0].ID] would be nil). Either Azure sometimes uses references to nics before they start showing up in az.netClient.listComplete(), or it's just that we do our "list nics" and "list instances" calls in the wrong order in Instances().

Either way, if ai.nic != nil && ... should fix it.