Re: [Qemu-devel] [PATCH 1/2] hw: timer: Add ASPEED RTC device

[Peter Maydell]

On Thu, 11 Apr 2019 at 17:37, Philippe Mathieu-Daudé <address@hidden> wrote:
>
> Hi Peter,
>
> On 4/11/19 5:30 PM, Cédric Le Goater wrote:
> > On 4/11/19 5:25 PM, Peter Maydell wrote:
> >> This is missing a reset function and vmstate.
>
> Is vmstate mandatory for new devices.

Yes, I think so. You can have vmstate that says
"this can't be migrated" if you absolutely must, but
it's generally easy enough to make it properly migratable.
If the device generally has no state to migrate it
should at least provide a comment saying so.
(I think we should add a way to say this in a vmstate,
so that we can then assert that every device sets its
vmsd pointer to something.)

Failing to provide a vmstate means you have a machine
which will silently break if the user tries to do
savevm/loadvm, which is not very nice.

thanks
-- PMM