[vbox-dev] (Bug?)VT-Bit

Klaus Espenlaub klaus.espenlaub at oracle.com
Fri Feb 3 18:27:04 GMT 2017


your comment is correct, but there's no point in this case. Recent 
VirtualBox versions on macOS simply require VT-x and can't do software 
virtualization. That's why the tab is greyed out there. You could beat 
on the config any way you like, it would still use VT-x. Even if you 
somehow manage to get around the sanity checks and hardcoded values, all 
you can achieve is that the VM wouldn't run.

Too much effort to describe the reason in detail, but it has to do with 
compilers and other macOS specific stuff.

All Apple boxes have CPUs with VT-x, which gives us the option to leave 
out the whole software virtualization blob.


On 03.02.2017 19:02, Ivo Smits wrote:
> The .vbox-prev(ious) is a backup file. I think it is overwritten with a
> copy of the .vbox file every now and then when the .vbox file is
> modified. The .vbox file is the actual configuration file, and the one
> you have to edit to make this work. It is recommended to close
> VirtualBox completely and wait several seconds (for the VBoxSVC process
> to shut down) before editing the file.
> --
> Ivo
> Op 3-2-2017 om 12:45 schreef Jd Lyons:
>> I changed my CPU from one that supports VT-x to one that doesn’t, now
>> none of my virtual machines will run
>> Failed to open a session for the virtual machine *Tiger*.
>> VT-x is not available (VERR_VMX_NO_VMX).
>> Result Code: 	NS_ERROR_FAILURE (0x80004005)
>> Component: 	ConsoleWrap
>> Interface: 	IConsole {872da645-4a9b-1727-bee2-5585105b9eed}
>> I edited the .vbox-prev of the virtual machines, and added:
>> <HardwareVirtEx enabled=“false”/>
>> But every time I launch VB, it overwrites the settings, removes
>> <HardwareVirtEx enabled=“false”/>.
>> I can’t access the Acceleration tab in VB, it’s greyed out, but it
>> must have the VT-x checkbox checked?
>> Is there some preference file I need to delete?
>> macOS Sierra 10.12.2
>> VB 5.1.14 r112924 (Qt5.6.2)

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