[Qemu-devel] Re: [PATCH] Make NIC model fallback to default when specified model is not supported

[Michal Novotny <minovotn@redhat.com>]

On 09/20/2010 12:34 PM, Paolo Bonzini wrote:
> On 09/20/2010 11:47 AM, Michal Novotny wrote:
>> Hi,
>>
>> this is the patch to introduce a NIC model fallback to default when 
>> model
>> specified is not supported. It's been tested on i386-softmmu target on
>> i386 host using the Windows XP x86 virtual machine and by trying to 
>> setup
>> the invalid (unsupported) model of NIC device. Also, the new constant in
>> the net.h called the DEFAULT_NIC_MODEL has been introduced to be able to
>> change the default NIC model easily. This variable is being used to set
>> the default NIC model when necessary.
>
> Why?  If it's not supported, it shouldn't run.
>
> Paolo

I don't think so. It makes sense it shouldn't run for case of pure qemu 
but since there's newly added support for xen (and also there's support 
for other virtualization platforms to be used with the qemu device 
model) it should fallback with just a warning since otherwise those 
platforms, like e.g. mentioned Xen, will leave defunct device models 
there and the guests won't run be running at all ending up with no 
state. If there's a warning with information it's falling back to 
default the user can notice if he wants to but it won't leave the 
defunct device models anymore which can be pretty hard to determine 
what's going on there for standard user that doesn't have much 
experience with e.g. Xen yet.

Michal

-- 
Michal Novotny<minovotn@redhat.com>, RHCE
Virtualization Team (xen userspace), Red Hat