`VZ` gets stuck waiting for `AdditionalSetupForSSH()`

[unsuman]

Description

When vz is built as an external driver it gets stuck waiting for AdditionalSetupForSSH() to complete when starting an instance but works fine when built as internal:

➜  lima2 git:(fix/ext-driver-residue) ✗ lm start
? Creating an instance "default" Proceed with the current configuration
INFO[0001] Starting the instance "default" with external VM driver "vz" 
INFO[0001] Attempting to download the image              arch=aarch64 digest="sha256:696b9ec765c0e3964b7845feb7217ef7e159e026c6b70eb0c8c2fed34e067067" location="https://cloud-images.ubuntu.com/releases/questing/release-20251023/ubuntu-25.10-server-cloudimg-arm64.img"
INFO[0001] Using cache "/Users/ansumansahoo/Library/Caches/lima/download/by-url-sha256/b33d6180955550f21ceb2308eba648114e93a71d7b81ff860b0e2f252c3656eb/data" 
INFO[0006] Attempting to download the nerdctl archive    arch=aarch64 digest="sha256:5398f037ae095d43cf3cb8c30765a24e511e38cafe02977b928a41b26e842ed1" location="https://github.com/containerd/nerdctl/releases/download/v2.2.0/nerdctl-full-2.2.0-linux-arm64.tar.gz"
INFO[0006] Using cache "/Users/ansumansahoo/Library/Caches/lima/download/by-url-sha256/e27422aaa9393572e7dc134eeb158f08328f22ca5e7556c80bdd221497a0a84a/data" 
INFO[0007] [hostagent] hostagent socket created at /Users/ansumansahoo/.lima/default/ha.sock 
^C

• Macbook Air M1(MacOS 26.1)
• limactl version 2.0.0-alpha.0-494-ge21b6346.m

[norio-nomura]

#4337 will fix this issue.

[norio-nomura]

Sorry, I don't test #4337 on external driver.

[unsuman]

I tested it but it seems not to be fixed.
driver.stderr.log:

time="2025-11-14T14:13:54+05:30" level=debug msg="Received AdditionalSetupForSSH request"
time="2025-11-14T14:13:54+05:30" level=debug msg="Received Start request"
time="2025-11-14T14:13:54+05:30" level=info msg="Starting VZ (hint: to watch the boot progress, see \"/Users/ansumansahoo/.lima/default/serial*.log\")"
time="2025-11-14T14:13:54+05:30" level=info msg="[VZ] - vm state change: running"
time="2025-11-14T14:14:03+05:30" level=info msg="Started vsock forwarder: 127.0.0.1:61534 -> vsock:22 on VM"
time="2025-11-14T14:14:03+05:30" level=info msg="Detected SSH server is listening on the vsock port; changed 127.0.0.1:61534 to proxy for the vsock port"

[unsuman]

In Go, every gRPC call has a new context so everytime limactl makes request to the driver instance the context is not the same, so I think the func AdditionalSetupForSSH() listens on a empty Go channel which blocks forever or maybe there is a race condition between Start() and AdditionalSetupForSSH()

[unsuman]

maybe there is a race condition between Start() and AdditionalSetupForSSH()

Actually this is the case, raising a fix

[norio-nomura]

In Go, every gRPC call has a new context so everytime limactl makes request to the driver instance the context is not the same,

Is that true? It seems that vz.New() is only called once.

[unsuman]

In Go, every gRPC call has a new context so everytime limactl makes request to the driver instance the context is not the same,

Is that true? It seems that vz.New() is only called once.

Not really, the state of the struct LimaVZDriver remains intact for all the gRPC calls after the driver instance is initialised