Disabling USB should disable EHCI as well

[jaspernbrouwer]

The way how disabling USB in the gui works is quite counter-intuitive and really annoying.

When you uncheck "Enable USB Controller", "Enable USB 2.0 (EHCI) Controller" is grayed out, which gives you the impression that it cannot be enabled when "Enable USB Controller" is disabled.

But this is not true:

Current functionality

Open box setting and go to "Ports" -> "USB".

Initial state:

• "Enable USB Controller" and "Enable USB 2.0 (EHCI) Controller" are both checked (on).

Action:

• Uncheck the box "Enable USB Controller".

Result:

• "Enable USB Controller" is unchecked (off).
• "Enable USB 2.0 (EHCI) Controller" is still checked (on), but grayed out.

This will result in the following entry in the box.ovf XML file:

<USBController enabled="false" enabledEhci="true"/>

Which will in turn result in Virtualbox trying to enable EHCI when bringing the box up, which will fail if you don't have the extension pack installed.

Expected functionality

Open box setting and go to "Ports" -> "USB".

Initial state:

• "Enable USB Controller" and "Enable USB 2.0 (EHCI) Controller" are both checked (on).

Action:

• Uncheck the box "Enable USB Controller".

Result:

• "Enable USB Controller" is unchecked (off).
• "Enable USB 2.0 (EHCI) Controller" is also unchecked (off), and grayed out.

This should result in the following entry in the box.ovf XML file:

<USBController enabled="false" enabledEhci="false"/>

[Frank Mehnert]

I see that the USB 2.0 checkbox is grayed and remains enabled if I disable USB for a VM. But in that case I'm still able to start the VM and I don't see any error message, even if there is no extension pack installed. Just tested this with VBox 4.3.12 on a Linux host. I don't think that Linux and Mac OS X differ here.

So may I ask you for a double-check that you are indeed not able to start the VM if there is no extension pack installed and you have USB 2.0 enabled but USB disabled?

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.