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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] don't require a disk image for network boot
Date: Thu, 15 Feb 2007 16:27:54 +0000
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To: qemu-devel@nongnu.org

On Thursday 15 February 2007 09:17, Thomas Petazzoni wrote:
> Hi,
>
> Le Tue, 13 Feb 2007 15:58:13 +0100,
>
> "andrzej zaborowski" <balrog@zabor.org> a =E9crit :
> > Subject: don't require a disk image for network boot
>
> BTW, is there a reason why a disk image is required when using the
> -kernel option ?
>
> In the following case: -kernel vmlinuz -append "nfsroot=3Dblabla", we
> could boot over the network, without the need for any disk image, but
> Qemu wants to have a disk image. Is it mandatory ?

The BIOS doesn't know about the -kernel option, so qemu replaces the first=
=20
sector of the disk image with a dummy bootloader that jumps to the preloade=
d=20
kernel. It can only do that if there is an image to replace.

Paul