Harvester UI · Reviewed

Saving an unchanged VM no longer asks for a restart

With the PCI Devices add-on on, opening Edit Config on a running VM and clicking Save without changing anything asked the user to restart the VM. The fix stops the form from adding an empty device list on its own, so an unchanged VM saves quietly.

Review done · approved PR 1206 ↗ Issue 12057 ↗ PR 1175 (depends on this) ↗

What changes for the user

Saving a VM without changes no longer shows the "Restart Virtual Machine" dialog. In our test today it showed 10 times out of 10 before the fix, and 0 out of 10 with it.
Users no longer risk restarting a running VM, and its workload, for nothing.
Adding or removing PCI and USB devices works as before, and still asks for a restart, which is correct there.
The bug only showed when the user stayed a few seconds on the form, which is normal use. It has been in every release since September 2024.
It also unblocks PR 1175, which skips the restart prompt for network-only changes.

The flow

Open Edit Config and change nothing

We open a running VM that has no PCI or USB devices and stay about 8 seconds on the form, like a user reading it.

The Edit Config form on the USB Devices tab, nothing selected, before and after — The form looks the same on both sides. No device is selected and we touch nothing.

Click Save: no more restart prompt

Before, Save asked to restart the running VM. After, the VM is saved and we are back on the list.

Before: Restart Virtual Machine dialog. After: back on the VM list, no dialog — Before, the form quietly added an empty device list to the VM. The VM looked changed, so Harvester asked for a restart. After the fix nothing is added, so there is nothing to restart for.

Adding a USB device is still saved

We pick a USB device and save. Both versions save it and ask for a restart, which is expected for new hardware.

A USB device selected and saved, same before and after — Same result on both sides: the save includes the new USB device.

Removing the last USB device is still saved

On a VM that has one USB device, we remove it and save. Both versions save the removal.

The USB device removed and saved, same before and after — The fix only skips the empty list when the VM never had devices. A real removal still goes through.

Video (optional)

0:00 Before · 0:22 After · 0:49 Adding a device still works

Notes

How we tested: the UI from current main and the same UI with the fix, both built and run from this laptop against our test Harvester. Every save was answered in the browser, so nothing on the cluster changed.
Our test Harvester has the PCI Devices add-on on, but no USB device is enabled for passthrough. For steps 3 and 4 we showed one USB device as enabled in the browser only, and in step 4 we showed it as already attached to the VM.
We asked for a Harvester issue and a backport in the review. Issue 12057 now exists, but it sits in the "Planning" backlog with no target release, and there is no backport yet.
The PR is approved by us and still waits for a Harvester maintainer. PR 1175 should merge after it.