Re: [Qemu-devel] diskimage HOWTO

[Laurent Vivier <Laurent@vivier.eu>]

Le lundi 24 août 2009 à 09:48 +0200, Kevin Wolf a écrit :
> Bai Shuwei schrieb:
> > Hi, All:
> >   I want to build a test enviroment with QEMU and buildroot. But I don't
> > know how to build the diskimage which same as linux-0.2.img offered by
> > BUILD-ROOT. I build the diskimage following the 
> >    buildroot-2009.05/docs/README.diskimage
> > <http://192.168.1.102/crosscopile/buildroot-2009.05/docs/README.diskimage>,
> > but failure.
> >  
> >    The bellow is my process.
> >  
> >    # dd if=/dev/zero of=img bs=4096 count=16384
> >    # echo -e "n\np\n1\n\nw\n" | fdisk -C 16065 -H 255 -S 63 ./img
> >    # losetup -o 512 /dev/loop0 img
> 
> This looks like the wrong offset. The first partition usually starts at
> sector 63. But probably you'll want to use kpartx which takes an image
> and creates device nodes for each partition.

You can also use loop module with max_part parameter (on a recent
kernel, 2.6.26, I think):

# rmmod loop
# modprobe loop max_part=16
# losetup -f /dev/loop0
# mount /dev/loop0p1 /mnt

If the disk image format is qcow2 you can use nbd module with max_part
parameter and qemu-nbd.

Regards,
Laurent
-- 
--------------------- laurent@vivier.eu ----------------------
"Tout ce qui est impossible reste à accomplir"    Jules Verne
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