Opened 2 years ago
Last modified 2 years ago
#21008 new defect
"Enable nested virtualization" button is bugged
| Reported by: | IL | Owned by: | |
|---|---|---|---|
| Component: | GUI | Version: | VirtualBox 6.1.34 |
| Keywords: | Cc: | ||
| Guest type: | all | Host type: | Windows |
Description
I downloaded and installed last VirtualBox version for Windows: 6.1.34 r150636 (Qt5.6.2). I ran a VM. Then I wanted to turn on nested virtualization in CPU's options, but the button was disabled (see screenshot attached). I have AMD Ryzen 5600x CPU and SMV is enabled in UEFI options.
I managed to figure out the problem spending some time on this: I used the console tool. This command works correctly: VBoxManage.exe modifyvm "test" --nested-hw-virt on The checkbox becomes being checked after that and nested virt is turned on. If I uncheck the checkbox again, it becomes inactive again.
Please, fix the checkbox. I didn't notice the issue with the other checkboxes.
Attachments (3)
Change History (10)
by , 2 years ago
| Attachment: | checkbox.JPG added |
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comment:1 by , 2 years ago
And, of course, the VM was turned off when I wanted to change the settings.
comment:2 by , 2 years ago
This VBoxManage command is independent on the capabilities of the current CPU, but the checkbox in the VirtualBox Manager is not. A few years ago I learned that this is deliberate behavior.
Please provide a (zipped) VBox.log file of a run of a VM showing this behavior. The VM doesn't need an installed OS for that. ;)
by , 2 years ago
comment:3 by , 2 years ago
Recorded one with the checkbox enabled.
From the log I found this:
00:00:02.438968 SVM - AMD Secure Virtual Machine extensions = 0 (0)
But this is wrong, I've SVM enabled, otherwise, my VM wouldn't start.
Also found this:
00:00:02.023891 CPUM: WARNING! Can't turn on nested VT-x/AMD-V when NEM is used''
What is NEM?
Is there anything anymore interesting?
comment:4 by , 2 years ago
Your Windows host OS is running under the Hyper-V hypervisor, which means that VirtualBox itself has no access to hardware virtualization (VT-x/AMD-V/SVM) and can only use the slower Native Execution Mode (NEM).
by , 2 years ago
| Attachment: | features.JPG added |
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comment:7 by , 2 years ago
I reviewed my machine in HWInfo and found the reason: HVCI (Hypervisor-protected code integrity) was enabled.
After turning it off (In Win10: Core Isolation -> Memory Protection option) the checkbox works as intended.
What VBox GUI could do is to handle this case somehow or add a notification to the checkbox tooltip.
Thanks, you can close the issue.


checkbox is inactive