[NotSupported] SLAT capabilities not supported in guest VM, but works on host

[Lanti]

I have Windows 10 18362.449 with Virtualbox 6.0.14 r133895 installed. I want to run Windows 10 18990 to test WSL2, so I need Hyper-V running in guest, but I'm getting the following error message when I try to enable Windows Subsystem for Linux (or Windows Sandbox, or hyper-V):

"The processor does not have Second Level Address Translation (SLAT) capabilities"

It's strange, because I enabled every virtualization related stuff in BIOS and Coreinfo on the host reports the following:

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AMD Ryzen 5 3600 6-Core Processor              
AMD64 Family 23 Model 113 Stepping 0, AuthenticAMD
Microcode signature: 00000000
HYPERVISOR	-	Hypervisor is present
SVM       	*	Supports AMD hardware-assisted virtualization
NP        	*	Supports AMD nested page tables (SLAT)

But in the guest VM, I'm getting the following:

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AMD Ryzen 5 3600 6-Core Processor              
AMD64 Family 23 Model 113 Stepping 0, AuthenticAMD
Microcode signature: 00000000
HYPERVISOR	*	Hypervisor is present
SVM       	*	Supports AMD hardware-assisted virtualization
NP        	-	Supports AMD nested page tables (SLAT)

I have Hyper-V installed, but I have a second boot option created with these commands:

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$ bcdedit /copy {current} /d "Windows 10 – No Hyper-V"
$ bcdedit /set {<CURRENT_ID>} hypervisorlaunchtype off

I'm attaching full Coreinfo logs as well and screenshots about my VM settings.

01.png (21.97 KiB) Viewed 12578 times

[socratis]

SLAT pass-through is not yet supported. That's one of the reasons that the only nested virtualization supported right now is VirtualBox-on-VirtualBox. Nothing else...

[Lanti]

Thank You for the information!

[socratis]

No problem. Marking as [NotSupported].

[gianluigi.zanettini]

Found this via Google for the same issue. Thanks socratis for clarifying the situation.

It looks like it's still the same today (May 2021), even with VirtualBox 6.1.22.