[Qemu-devel] Cannot launch QEMU with -accel whpx

[Qemu-devel] Cannot launch QEMU with -accel whpx

[Wang Wenchao]

Hi, Justin,

We are interested in WHPX but haven't got it to work. We were able to 
build QEMU with WHPX support. We used MSYS2 build environment plus two 
libraries (WinHv*.lib) from the latest Windows 10 SDK Insider Preview to 
build QEMU and added '--enable-whpx' parameter in config. But when we 
ran it on Windows with Hyper-V on, QEMU failed to be launched.

The command to launch QEMU is as below,

 > qemu-system-x86_64.exe -accel whpx

The following errors were output from the command line,

qemu-system-x86_64.exe: WHPX: No accelerator found, hr=00000000
qemu-system-x86_64.exe: failed to initialize WHPX: No space left on device

We analyzed the issue and found when invoking the Windows Hypervisor 
Platform API WHvGetCapability(), it returned whpx_cap.HypervisorPresent 
with FALSE and then WHPX failed to initialize. Do you have any 
suggestion on that? Thanks.

We build and run QEMU on the same machine. Below are its specs,

Windows OS: Windows 10 Insider Preview
Windows edition: Professional
Windows version: 1803 (OS build 17133.1)
SDK version: 10.0.17125.0

Processor: Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz 1.99GHz
RAM: 8.00 GB
System Type: 64-bit Operating System, x64-based processor


Best Regards,
Wenchao

Re: [Qemu-devel] Cannot launch QEMU with -accel whpx

[Justin Terry (VM)]

Hey Wenchao,

It looks like your specs should fully support running this. Did you by chance forget to enable the Windows optional feature? Having the lib/dll’s from the SDK isn’t all you need.

Try:
(admin) PS> Enable-WindowsOptionalFeature -Online -FeatureName HypervisorPlatform
(reboot the machine)
> qemu-system-x86_64.exe -accel whpx …

Let me know if that wasn’t the issue.

Thanks,
Justin

From: Wang Wenchao <wenchao.wang@linux.intel.com>
Sent: Thursday, April 26, 2018 3:47 AM
To: Justin Terry (VM) <juterry@microsoft.com>
Cc: qemu-devel@nongnu.org
Subject: Cannot launch QEMU with -accel whpx

Hi, Justin,

We are interested in WHPX but haven't got it to work. We were able to build QEMU with WHPX support. We used MSYS2 build environment plus two libraries (WinHv*.lib) from the latest Windows 10 SDK Insider Preview to build QEMU and added '--enable-whpx' parameter in config. But when we ran it on Windows with Hyper-V on, QEMU failed to be launched.

The command to launch QEMU is as below,

> qemu-system-x86_64.exe -accel whpx

The following errors were output from the command line,

qemu-system-x86_64.exe: WHPX: No accelerator found, hr=00000000
qemu-system-x86_64.exe: failed to initialize WHPX: No space left on device

We analyzed the issue and found when invoking the Windows Hypervisor Platform API WHvGetCapability(), it returned whpx_cap.HypervisorPresent with FALSE and then WHPX failed to initialize. Do you have any suggestion on that? Thanks.

We build and run QEMU on the same machine. Below are its specs,

Windows OS: Windows 10 Insider Preview
Windows edition: Professional
Windows version: 1803 (OS build 17133.1)
SDK version: 10.0.17125.0

Processor: Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz 1.99GHz
RAM: 8.00 GB
System Type: 64-bit Operating System, x64-based processor


Best Regards,
Wenchao

Re: [Qemu-devel] Cannot launch QEMU with -accel whpx

[Wang Wenchao]

Hi, Justin,

That hits the issue. QEMU can be launched with WHPX enabling. Great 
thanks for your reply.


Best Regards,
Wenchao

On 4/27/2018 2:06, Justin Terry (VM) wrote:
>
> Hey Wenchao,
>
> It looks like your specs should fully support running this. Did you by 
> chance forget to enable the Windows optional feature? Having the 
> lib/dll’s from the SDK isn’t all you need.
>
> Try:
>
> (admin) PS> Enable-WindowsOptionalFeature -Online -FeatureName 
> HypervisorPlatform
>
> (reboot the machine)
>
> > qemu-system-x86_64.exe -accel whpx …
>
> Let me know if that wasn’t the issue.
>
> Thanks,
>
> Justin
>
> *From:*Wang Wenchao <wenchao.wang@linux.intel.com>
> *Sent:* Thursday, April 26, 2018 3:47 AM
> *To:* Justin Terry (VM) <juterry@microsoft.com>
> *Cc:* qemu-devel@nongnu.org
> *Subject:* Cannot launch QEMU with -accel whpx
>
> Hi, Justin,
>
> We are interested in WHPX but haven't got it to work. We were able to 
> build QEMU with WHPX support. We used MSYS2 build environment plus two 
> libraries (WinHv*.lib) from the latest Windows 10 SDK Insider Preview 
> to build QEMU and added '--enable-whpx' parameter in config. But when 
> we ran it on Windows with Hyper-V on, QEMU failed to be launched.
>
> The command to launch QEMU is as below,
>
> > qemu-system-x86_64.exe -accel whpx
>
> The following errors were output from the command line,
>
> qemu-system-x86_64.exe: WHPX: No accelerator found, hr=00000000
> qemu-system-x86_64.exe: failed to initialize WHPX: No space left on device
>
> We analyzed the issue and found when invoking the Windows Hypervisor 
> Platform API WHvGetCapability(), it returned 
> whpx_cap.HypervisorPresent with FALSE and then WHPX failed to 
> initialize. Do you have any suggestion on that? Thanks.
>
> We build and run QEMU on the same machine. Below are its specs,
>
> Windows OS: Windows 10 Insider Preview
> Windows edition: Professional
> Windows version: 1803 (OS build 17133.1)
> SDK version: 10.0.17125.0
>
> Processor: Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz 1.99GHz
> RAM: 8.00 GB
> System Type: 64-bit Operating System, x64-based processor
>
>
> Best Regards,
> Wenchao
>