From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: systemcalls and kvm ...correct me if I am wrong
Date: Sun, 07 Jun 2009 13:33:38 +0300
Message-ID: <4A2B9782.1070503@redhat.com>
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Cc: kvm@vger.kernel.org
To: Matteo Signorini <signorinimatteo@gmail.com>
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Matteo Signorini wrote:
> Hi to all,
>
> correct me if I am wrong but isn't it the following the logical
> execution chain of a generic system call performed
> in a Kvm guest?
>
> Guest userspace application -> Guest kernel -> Host kernel (kvm) ->
> Host userspace (Quemu) -> Host kernel ->
> -> Host userspace (Quemu) -> Guest kernel -> Guest userspace application
>
>   

No.  The actual path is

   guest userspace -> guest kernel -> guest userspace

The guest kernel might access emulated hardware, but usually it does not.

> Is there any detailed documentation on how this happens inside qemu-kvm?
>   

No.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.