Running KVM inside a KVM guest.

Running KVM inside a KVM guest.

[jd]

Hi
  Is it possible to install and use KVM in a guest VM ? I need this for testing so, a reasonable performance is fine. 

  Anyone who has tried this ? Any known gotchas, workarounds ? Any particular version of KVM required ?

Thanks
/Jd


      

Re: Running KVM inside a KVM guest.

[Alexander Graf]

Hi jd,

On 14.10.2008, at 01:34, jd wrote:

> Hi
>  Is it possible to install and use KVM in a guest VM ? I need this  
> for testing so, a reasonable performance is fine.

Yes, with AMD CPUs and my "nested KVM" patchset. I am planning to  
improve it this week (if my tooth operation goes well :-(), so we can  
finally get it upstream :-). I sent v3 about 3 weeks ago, just search  
for it in the archives.
You also need to take Joerg's patch to emulate the VM_CR MSR. That  
particular patch is in a follow-up mail of v3.

>  Anyone who has tried this ? Any known gotchas, workarounds ? Any  
> particular version of KVM required ?

SMP doesn't work and Ubuntu's timestamp stays at 0 on bootup. That's  
all issues that should concern you atm.

Alex

Re: Running KVM inside a KVM guest.

[jd]

Hi Alex, 
  Wish u good luck for your operation. 
  Good to hear that this is possible and on AMD, as I have one AMD machine that I can play around with. I will try it out when I get a chance.

Thanks
/Jd


--- On Tue, 10/14/08, Alexander Graf <agraf@suse.de> wrote:

> From: Alexander Graf <agraf@suse.de>
> Subject: Re: Running KVM inside a KVM guest.
> To: jdsw2002@yahoo.com
> Cc: "KVM List" <kvm@vger.kernel.org>
> Date: Tuesday, October 14, 2008, 12:58 AM
> Hi jd,
> 
> On 14.10.2008, at 01:34, jd wrote:
> 
> > Hi
> >  Is it possible to install and use KVM in a guest VM ?
> I need this  
> > for testing so, a reasonable performance is fine.
> 
> Yes, with AMD CPUs and my "nested KVM" patchset.
> I am planning to  
> improve it this week (if my tooth operation goes well :-(),
> so we can  
> finally get it upstream :-). I sent v3 about 3 weeks ago,
> just search  
> for it in the archives.
> You also need to take Joerg's patch to emulate the
> VM_CR MSR. That  
> particular patch is in a follow-up mail of v3.
> 
> >  Anyone who has tried this ? Any known gotchas,
> workarounds ? Any  
> > particular version of KVM required ?
> 
> SMP doesn't work and Ubuntu's timestamp stays at 0
> on bootup. That's  
> all issues that should concern you atm.
> 
> Alex


      

Re: Running KVM inside a KVM guest.

[jd]

Hi Alex
   Hope your tooth op went smoothly.
   Did u get a chance to put up your new version of the nested KVM patch ?
   I am on KVM-70... can u tell me in bit more details on how I can go about getting your patches and Joerg's patch applied.
  -- What versions of KVM are these patches expected to work with ? 
  -- Any sequencing or they are non-overlapping.
  -- Do I need to upgrade to some later version of KVM ?
  -- Are these patches already part of KVM-78 ?

Thanks
/Jd


--- On Tue, 10/14/08, Alexander Graf <agraf@suse.de> wrote:

> From: Alexander Graf <agraf@suse.de>
> Subject: Re: Running KVM inside a KVM guest.
> To: jdsw2002@yahoo.com
> Cc: "KVM List" <kvm@vger.kernel.org>
> Date: Tuesday, October 14, 2008, 12:58 AM
> Hi jd,
> 
> On 14.10.2008, at 01:34, jd wrote:
> 
> > Hi
> >  Is it possible to install and use KVM in a guest VM ?
> I need this for testing so, a reasonable performance is
> fine.
> 
> Yes, with AMD CPUs and my "nested KVM" patchset.
> I am planning to improve it this week (if my tooth operation
> goes well :-(), so we can finally get it upstream :-). I
> sent v3 about 3 weeks ago, just search for it in the
> archives.
> You also need to take Joerg's patch to emulate the
> VM_CR MSR. That particular patch is in a follow-up mail of
> v3.
> 
> >  Anyone who has tried this ? Any known gotchas,
> workarounds ? Any particular version of KVM required ?
> 
> SMP doesn't work and Ubuntu's timestamp stays at 0
> on bootup. That's all issues that should concern you
> atm.
> 
> Alex
> --
> To unsubscribe from this list: send the line
> "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at 
> http://vger.kernel.org/majordomo-info.html


      

Re: Running KVM inside a KVM guest.

[Alexander Graf]

Hey Jd,

On 14.11.2008, at 04:07, jd wrote:

> Hi Alex
>   Hope your tooth op went smoothly.
>   Did u get a chance to put up your new version of the nested KVM  
> patch ?

I'm still working on it. I'll post a new version this week that I'll  
try to accelerate a bit further.

>   I am on KVM-70... can u tell me in bit more details on how I can  
> go about getting your patches and Joerg's patch applied.
>  -- What versions of KVM are these patches expected to work with ?

Always against current git. But with a bit of fiddling you should be  
able to get it working with "moderately recent" versions too. The SVM  
code hasn't changed that much for quite a while - the files just moved.

>  -- Any sequencing or they are non-overlapping.

Sequencing is in the subjects.

>  -- Do I need to upgrade to some later version of KVM ?
>  -- Are these patches already part of KVM-78 ?

No. As soon as they are merged to git, they'll show up in the next  
snapshot.

Alex

>
>
> Thanks
> /Jd
>
>
> --- On Tue, 10/14/08, Alexander Graf <agraf@suse.de> wrote:
>
>> From: Alexander Graf <agraf@suse.de>
>> Subject: Re: Running KVM inside a KVM guest.
>> To: jdsw2002@yahoo.com
>> Cc: "KVM List" <kvm@vger.kernel.org>
>> Date: Tuesday, October 14, 2008, 12:58 AM
>> Hi jd,
>>
>> On 14.10.2008, at 01:34, jd wrote:
>>
>>> Hi
>>> Is it possible to install and use KVM in a guest VM ?
>> I need this for testing so, a reasonable performance is
>> fine.
>>
>> Yes, with AMD CPUs and my "nested KVM" patchset.
>> I am planning to improve it this week (if my tooth operation
>> goes well :-(), so we can finally get it upstream :-). I
>> sent v3 about 3 weeks ago, just search for it in the
>> archives.
>> You also need to take Joerg's patch to emulate the
>> VM_CR MSR. That particular patch is in a follow-up mail of
>> v3.
>>
>>> Anyone who has tried this ? Any known gotchas,
>> workarounds ? Any particular version of KVM required ?
>>
>> SMP doesn't work and Ubuntu's timestamp stays at 0
>> on bootup. That's all issues that should concern you
>> atm.
>>
>> Alex
>> --
>> To unsubscribe from this list: send the line
>> "unsubscribe kvm" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at
>> http://vger.kernel.org/majordomo-info.html
>
>
>