Enable Nested VT-X/AMD-V not working

Discussions related to using VirtualBox on Windows hosts.
Post Reply
LondonPerry
Posts: 4
Joined: 2. Feb 2023, 00:03

Enable Nested VT-X/AMD-V not working

Post by LondonPerry »

I am having the exact same issue. Did you find an answer?

I have an i7-1206p processor, and it supports all virtual settings. Enable nested VT-x/AMD-V was grayed out originally so I had to manually enable with VBoxManage modifyvm "computerName" --nested-hw-virt on to get it to turn on. But it doesn't show next to Acceleration on preview window. I am thinking that this may be a problem with 7.0 branch. I have read that 7.0 has alot of issues. See attached file.
Attachments
Untitled.png
Untitled.png (54.17 KiB) Viewed 6600 times
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: Enable Nested VT-X/AMD-V not working

Post by scottgus1 »

On the Windows host level, Start the VM from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the VM from within the VM's OS if possible. If not possible, close the Virtualbox window for the VM with the Power Off option set.

Right-click the VM in the main Virtualbox window's VM list, choose Show in Explorer/Finder/File Manager. In the "Logs" subfolder, zip the VM's "vbox.log", and post the zip file, using the forum's Upload Attachment tab. (Configure your host OS to show all extensions so you can find the "vbox.log", not "vbox.log.1", etc.)
LondonPerry
Posts: 4
Joined: 2. Feb 2023, 00:03

Re: Enable Nested VT-X/AMD-V not working

Post by LondonPerry »

Here is log. The error is a windows error so I am not sure how this will mater.
Attachments
VBox.zip
(39.88 KiB) Downloaded 49 times
mpack
Site Moderator
Posts: 39156
Joined: 4. Sep 2008, 17:09
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Mostly XP

Re: Enable Nested VT-X/AMD-V not working

Post by mpack »

Why do you believe you need to enable nested VT-x? You may have a valid reason to reflect VT-x into the VM, but you may also be confusing it with the plain VT-x that VirtualBox uses on the host.

In any case the reason the feature is not available if that you have Hyper-v running.
00:00:10.755043 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
00:00:10.769346 NEM: info: Found optional import WinHvPlatform.dll!WHvQueryGpaRangeDirtyBitmap.
00:00:10.769357 NEM: info: Found optional import vid.dll!VidGetHvPartitionId.
00:00:10.769360 NEM: info: Found optional import vid.dll!VidGetPartitionProperty.
00:00:10.769401 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work...
Obviously VirtualBox can't reflect VT-x into the VM when VT-x is not available.

For info on how to disable Hyper-v, see HMR3Init: Attempting fall back to NEM (Hyper-V is active).
LondonPerry
Posts: 4
Joined: 2. Feb 2023, 00:03

Re: Enable Nested VT-X/AMD-V not working

Post by LondonPerry »

I saw that but haven't found a way to get it turned off.

I have removed the feature from control panel and run DISM /Online /Disable-Feature:Microsoft-Hyper-V

I am trying to run docker inside a Vbox guest.

I followed these instructions (beebom how-disable-virtualization-based-security-vbs-windows-11), and I can actually check the box now and my log is diiferent.

HM: HMR3Init: VT-x w/ nested paging and unrestricted guest execution hw support
00:00:11.791675 CPUM: fXStateHostMask=0x7; initial: 0x7; host XCR0=0x7
00:00:11.794855 CPUM: Matched host CPU INTEL 0x6/0x9a/0x3 Intel_Core7_AlderLake with CPU DB entry 'Intel Core i7-6700K' (INTEL 0x6/0x5e/0x3 Intel_Core7_Skylake)
00:00:11.794909 CPUM: MXCSR_MASK=0xffff (host: 0xffff)
Attachments
VBox.zip
(32.68 KiB) Downloaded 21 times
BillG
Volunteer
Posts: 5102
Joined: 19. Sep 2009, 04:44
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows 10,7 and earlier
Location: Sydney, Australia

Re: Enable Nested VT-X/AMD-V not working

Post by BillG »

LondonPerry wrote:
I am trying to run docker inside a Vbox guest.
I don't like your chances of ever getting that to work in a VirtualBox vm. Docker in a vm would require the Windows hypervisor running in the vm (that is, Hyper-V nested in VirtualBox).

It might work in a Hyper-V vm (i.e Hyper-V nested in Hyper-V).
Bill
LondonPerry
Posts: 4
Joined: 2. Feb 2023, 00:03

Re: Enable Nested VT-X/AMD-V not working

Post by LondonPerry »

Yep, I have already moved to Hyper-V and it works good. I have always been a fan of virtualbox but I guess it is time to learn something new.
mpack
Site Moderator
Posts: 39156
Joined: 4. Sep 2008, 17:09
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Mostly XP

Re: Enable Nested VT-X/AMD-V not working

Post by mpack »

LondonPerry wrote:I saw that but haven't found a way to get it turned off.
My post included a link which tells you about that.
Post Reply