Re: [Qemu-devel] [PATCH 1/2] hw: cannot_instantiate_with_device_add_yet due to pointer props

[Peter Crosthwaite]

On Tue, Jan 7, 2014 at 10:43 PM, Peter Maydell <address@hidden> wrote:
> On 7 January 2014 12:33, Andreas Färber <address@hidden> wrote:
>> Am 16.12.2013 10:33, schrieb Peter Maydell:
>>> Anyway, I don't actively object to this series. I just think
>>> Anthony's going in the wrong direction which is why I haven't
>>> been particularly eager to actively mark it as reviewed-by me
>>> either...
>>
>> Sorry for not taking the time to reply to these concerns earlier. I
>> thought it was self-speaking that the enterprise Linux distributors
>> among us want a safeguard to avoid customers from crashing a
>> long-running VM with some avoidable device_add.
>
> Sure. I think the right way to do that is to only allow
> them to plug in devices that are truly pluggable (ie which
> are on some pluggable bus like PCI or USB), rather than
> this way round, which is trying to blacklist devices rather
> than whitelist bus types.
>

If you bring FPGAs into the game, SYSBUS itself is ultimately
pluggable. All sysbus devices under the sun are therefore legitimately
"pluggable" in target-microblaze.

Regards,
Peter


> In short, we shouldn't be trying to cram all of "hotplug",
> "I want an extra PCI card in my VM" and "I want to do
> complete from-scratch construction of a machine model
> including wiring up all the interrupts and defining the
> memory map" into the same interface, because the flexibility
> you need for the last one of these is going to cause endless
> user errors when attempting the first two.
>
> thanks
> -- PMM
>