From: Anthony Liguori <anthony@codemonkey.ws>
To: Glauber Costa <glommer@gmail.com>
Cc: Bryan McLellan <btm@loftninjas.org>, kvm@vger.kernel.org
Subject: Re: Accessing pv_info from userland
Date: Sat, 31 Jan 2009 13:36:05 -0600 [thread overview]
Message-ID: <4984A825.3020904@codemonkey.ws> (raw)
In-Reply-To: <5d6222a80901310504x76363751p9c28a63a3f01530@mail.gmail.com>
Glauber Costa wrote:
> On Sat, Jan 31, 2009 at 10:19 AM, Bryan McLellan <btm@loftninjas.org> wrote:
>
>> Is there any way to access pv_info from userland? It would be useful
>> for determining what type of virtualization the machine was running
>> on.
>>
>
> there are usually cpuid functions reserved for that.
>
> for kvm, you can run function 0x40000000, and if you get
> ebx = 0x4b4d564b
> ecx = 0x564b4d56
> edx = 0x4d
>
> you're running KVM.
>
Since this is a pretty standard mechanism, it may make sense to include
this signature in /proc/cpuinfo if someone is up to writing a patch. It
could also be useful to expose the PV features mask in cpuinfo too.
Regards,
Anthony Liguori
next prev parent reply other threads:[~2009-01-31 19:36 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-31 12:19 Accessing pv_info from userland Bryan McLellan
2009-01-31 13:04 ` Glauber Costa
2009-01-31 19:36 ` Anthony Liguori [this message]
2009-01-31 19:55 ` Glauber Costa
2009-01-31 20:20 ` Bryan McLellan
2009-01-31 20:26 ` Glauber Costa
2009-01-31 21:08 ` Anthony Liguori
2009-01-31 21:18 ` Alexander Graf
2009-02-01 0:55 ` Anthony Liguori
2009-02-01 17:56 ` Alexander Graf
2009-02-03 10:50 ` Avi Kivity
2009-02-03 15:02 ` Glauber Costa
2009-02-04 14:16 ` Avi Kivity
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