From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: kvm + kqemu enabled at the same time
Date: Wed, 29 Oct 2008 09:21:24 +0200
Message-ID: <49080EF4.4090307@redhat.com>
References: <200810282220.59240.kejda@centrum.cz> <49078CF8.9070704@codemonkey.ws>
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Cc: =?ISO-8859-1?Q?Martin_Kej=EDk?= <kejda@centrum.cz>,
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To: Anthony Liguori <anthony@codemonkey.ws>
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Anthony Liguori wrote:
> Martin Kej=EDk wrote:
>> Hello,
>> I've compiled the KVM enabled QEMU with support for both KVM and=20
>> KQEMU. Both modules loaded and
>> QEMU running saying "kvm: enabled" and "kqemu: enabled for user code=
".
>>
>> How does this work?? What does QEMU really do in this situation when=
=20
>> we look closer to CPU??
>>  =20
>
> You're using both accelerators at the same time and getting 2x=20
> acceleration.  It will actually go faster than native now :-)
>
> Seriously, it's working based on sheer luck.  If you look at the=20
> cpu_exec() loop (which is the core execution loop in QEMU, you'll see=
):

Is cpu_exec() actually executed with kvm?  I think we fork vcpu threads=
=20
and jump to our own little main loop before that.

--=20
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.