Setextradata HOSTCPUID CPUM not working?

Discussions about using Windows guests in VirtualBox.

Setextradata HOSTCPUID CPUM not working?

Postby FlatChad » 14. Apr 2016, 08:32

I have a Windows 7 x86 Guest that is powered off. I run:

Code: Select all   Expand viewCollapse view
vboxmanage setextradata "Win7-x86-SP1" VBoxInternal/CPUM/HostCPUID/00000001/eax 0x000506E3
vboxmanage setextradata "Win7-x86-SP1" VBoxInternal/CPUM/HostCPUID/00000001/ebx 0x00040800
vboxmanage setextradata "Win7-x86-SP1" VBoxInternal/CPUM/HostCPUID/00000001/ecx 0x1ED82203
vboxmanage setextradata "Win7-x86-SP1" VBoxInternal/CPUM/HostCPUID/00000001/edx 0x178BFBBF


I can see the changes have all been applied successfully by viewing the .vbox file.

I start the VM, and immediately the .vbox is modified, removing the 4 settings I just applied.

As a result, the CPUID instruction does not return these values when executed.

What am I doing wrong?
Attachments
vbox.log
(109.11 KiB) Downloaded 28 times
FlatChad
 
Posts: 1
Joined: 14. Apr 2016, 08:18

Re: Setextradata HOSTCPUID CPUM not working?

Postby michaln » 14. Apr 2016, 11:37

FlatChad wrote:What am I doing wrong?

You're using an undocumented internal interface. Why are you doing that, anyway?

Use 'VBoxManage modifyvm <vmname> -- cpuidset <leaf> <eax> <ebx> <ecx> <edx>' instead.
michaln
Oracle Corporation
 
Posts: 2841
Joined: 19. Dec 2007, 15:45
Primary OS: MS Windows 7
VBox Version: PUEL
Guest OSses: Any and all

Re: Setextradata HOSTCPUID CPUM not working?

Postby brunis » 4. Dec 2017, 15:09

Amazing, love how this official interface breaks my vm's. At least the undocumented one didn't.

Any idea how to unbreak my vm's if i tried any of the cpuid's on the list?

--cpuidremoveall has no effect.. or maybe that's because it's entires wiped now?
brunis
 
Posts: 1
Joined: 4. Dec 2017, 15:01

Re: Setextradata HOSTCPUID CPUM not working?

Postby socratis » 4. Dec 2017, 17:55

I thought that repeating the command with no arguments:
    VBoxManage modifyvm <vmname> --cpuidset
would work, alas it doesn't. So the only way I can think of is to quit VirtualBox and make sure that there are no VirtualBox processes running (VBox*, VM*). Another way would be to reboot your host and avoid launching VirtualBox.

You then edit the .vbox file of the affected machine and you delete three lines:
<CpuIdTree>
<CpuIdLeaf id="1" eax="198313" ebx="1050624" ecx="2140857279" edx="126614527"/>
</CpuIdTree>

The e*x numbers may be different in your case.
If you obfuscate any information requested, I will obfuscate my response. These are virtual UUIDs, not real ones.
Do NOT reply with the "QUOTE" button, please use the "POST REPLY", at the bottom of the form.
socratis
Site Moderator
 
Posts: 12648
Joined: 22. Oct 2010, 11:03
Location: Greece
Primary OS: Mac OS X other
VBox Version: PUEL
Guest OSses: Win(*>98), Linux*, OSX>10.5

Re: Setextradata HOSTCPUID CPUM not working?

Postby michaln » 7. Dec 2017, 10:32

What *exactly* is the problem, and what are you trying to solve by modifying the CPUID? Chances are you're doing something wrong/unnecessary. Without knowing the details, the general advice is "don't do this".
michaln
Oracle Corporation
 
Posts: 2841
Joined: 19. Dec 2007, 15:45
Primary OS: MS Windows 7
VBox Version: PUEL
Guest OSses: Any and all


Return to Windows Guests

Who is online

Users browsing this forum: No registered users and 15 guests