Problem with a RAW Disk and Xen

[Jim Fehlig]

On 8/27/20 2:47 PM, Christoph wrote:
>>
>> Using blkback works for me, e.g. <driver name='phy'...>.
>>
> what is the diff to 'qemu'?

It's just a different block backend. Xen supports both qemu as a block backend 
and blkback. blkback only supports raw IIRC. And apparently, when used with Xen, 
the qemu backend only support rw.

>> What xl config did you use? It doesn't work for me if I specify qdisk
>> and readonly. E.g. the following does not work
>>
>> "backendtype=qdisk,format=raw,vdev=xvdz,access=ro,target=..."
>>
> 
> "phy:/dev/mapper/keys,xvdz,r"

As expected you are using blkback.

Regards,
Jim