[Bug]: Windows 11 25H2 host — Intermittent VM freezes using NEM/WHPX with VBS enabled (Ryzen 9950X3D)

Ouverte
  • Quelque chose ne va pas ?
#972 1 commentaire 1 réaction 0 personnes assignées Voir sur GitHub

Les mainteneurs répondent en général sous 6 jours

Personne n'a encore pris cette issue.

Évaluation

Difficulté
4/5
Temps estimé
3-5 jours
Accessibilité débutants
35/100
Type d'issue
Bug
Clarté
Plutôt claire
Activité
Active
Stack technique
c
Domaine
backend, operating-systems

Piste de recherche

Start by reading the attached sanitized log and tracing the NEM/WHPX initialization and guest heartbeat paths mentioned in the report. The issue provides no source files or failing test, and the freeze is intermittent, so first identify a reproducible diagnostic path; done means the guest remains responsive with Windows virtualization-based security enabled or the cause and supported workaround are documented.

Rédigé par le modèle d'indexation à partir du texte de l'issue.

Description

bug
Version

7.2.20

Host OS Type

Windows

Host OS name + version

Windows 11 Pro 10.0.26200 Build 26200

Host Architecture

x86

Guest OS Type

Windows

Guest Architecture

x86

Guest OS name + version

Both Windows and Linux VMs

Component

GUI

What happened?

Environment
VirtualBox: 7.2.20 r175154
Host OS: Windows 11, build 26200.9711
Host architecture: x86-64
Processor: AMD Ryzen 9 9950X3D
Host RAM: 32 GB
Guest OS: Windows 11 64-bit
Guest RAM: 6 GB
Guest processors: 8 vCPUs
Graphics: VMSVGA, 3D acceleration disabled
Windows Core Isolation / Memory Integrity: Enabled
Component: VMM / NEM / Windows Hypervisor Platform

Description

I am experiencing recurring, intermittent freezes of VirtualBox virtual machines on my Windows 11 workstation. Includes both Windows and Linux OS machines.

The issue has persisted across multiple VirtualBox updates over several months. I previously used VirtualBox on an Intel-based Windows 10 computer without experiencing this behavior.

The Windows 11 host has its normal virtualization-based security features enabled. VirtualBox falls back to the Windows Hypervisor Platform (NEM/WHPX) rather than accessing AMD-V directly.

The attached log explicitly reports that NEM's reduced-performance execution mode is active, followed by guest heartbeat failures.

Relevant log entries

HM: HMR3Init: Attempting fall back to NEM:
AMD-V is not available

NEM: WHvCapabilityCodeHypervisorPresent is TRUE

[VirtualBox_Win11_25H2_Sanitized_Log.txt](https://github.com/user-attachments/files/34638673/VirtualBox_Win11_25H2_Sanitized_Log.txt)

NEM: NEMR3Init: Snail execution mode is active!

The guest subsequently becomes unresponsive:

00:04:33 Guest seems to be unresponsive.
Last heartbeat received 4 seconds ago

00:04:54 GuestHeartBeat: Guest is alive

00:04:59 Guest seems to be unresponsive.
Last heartbeat received 5 seconds ago
How can we reproduce this?

Run an existing Windows 11 guest in VirtualBox on the described Windows 11 host.
Leave the host's default security features, including Memory Integrity, enabled.
Start the VM while VirtualBox is using the NEM/WHPX execution backend.
Use the guest normally and observe intermittent freezes and heartbeat failures.
The issue is intermittent rather than reliably triggered by a particular application.

VirtualBox reports reduced-performance NEM execution mode, and the guest experiences intermittent periods of unresponsiveness.

Troubleshooting performed
Tested multiple VirtualBox versions over several months.
Confirmed the host hypervisor is active.
Confirmed VirtualBox is using NEM/WHPX.
Captured guest heartbeat failures in the VirtualBox log.

I would prefer to retain Windows 11's built-in security protections, including Memory Integrity and virtualization-based security.

Could the VirtualBox development team investigate whether this is a known Windows 11 NEM/WHPX compatibility or scheduling issue?

Is there a planned correction, development build, or supported workaround that allows VirtualBox to operate reliably while Windows virtualization-based security remains enabled?

Please advise whether additional diagnostic traces would help identify the cause.

Attachment: VirtualBox_Win11_25H2_Sanitized_Log.txt

Did you upload all of your necessary log files, screenshots, etc.?
  • Yes, I've uploaded all pertinent files to this issue.
Langage dominant
C
Étoiles
1.4k
Forks
219
Aucune PR mergée en 30 j

Préparer son environnement

Par où commencer

  1. Lisez l'issue en entier, puis le guide de contribution du projet.
  2. Signalez en commentaire que vous la prenez — cela évite que deux personnes fassent le même travail.
  3. Forkez le dépôt et travaillez sur une branche.
  4. Ouvrez une pull request qui référence le numéro de l'issue.

Autres issues de VirtualBox/virtualbox

Toutes les issues de VirtualBox/virtualbox

Issues similaires

Plus d'issues C

Recevez les nouvelles issues par e-mail

Un résumé court des issues GitHub adaptées aux débutants.