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

Aperta
  • Qualcosa non va?
#972 1 commento 1 reazione 0 assegnatari Vedi su GitHub

I maintainer di solito rispondono entro 6 giorni

Nessuno ha ancora preso questa issue.

Valutazione

Difficoltà
4/5
Tempo stimato
3-5 giorni
Idoneità per principianti
35/100
Tipo di issue
Bug
Chiarezza
Abbastanza chiara
Stato di attività
Attiva
Stack tecnologico
c
Ambito
backend, operating-systems

Direzione di ricerca

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.

Scritto dal modello di indicizzazione a partire dal testo della issue.

Descrizione

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.
Lingua principale
C
Stelle
1.4k
Fork
219
Nessuna PR unita negli ultimi 30g

Preparare l'ambiente

Come iniziare

  1. Leggi tutta la issue e poi la guida ai contributi del progetto.
  2. Commenta sulla issue per dire che te ne occupi tu — evita che due persone facciano lo stesso lavoro.
  3. Fai un fork del repository e lavora su un branch.
  4. Apri una pull request che faccia riferimento al numero della issue.

Altre issue di VirtualBox/virtualbox

Tutte le issue di VirtualBox/virtualbox

Issue simili

Altre issue su C

Ricevi le nuove issue nella tua casella

Un breve riepilogo di issue GitHub adatte ai principianti.