Re: [Qemu-devel] [PATCH v3 3/3] pc-dimm: factor out address space logic into MemoryDevice code

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 23 Apr 2018 14:52:37 +0200
David Hildenbrand <david@redhat.com> wrote:

> >   
> >> +    /* we will need a new memory slot for kvm and vhost */
> >> +    if (kvm_enabled() && !kvm_has_free_slot(machine)) {
> >> +        error_setg(errp, "hypervisor has no free memory slots left");
> >> +        return;
> >> +    }
> >> +    if (!vhost_has_free_slot()) {
> >> +        error_setg(errp, "a used vhost backend has no free memory slots left");
> >> +        return;
> >> +    }  
> > move these checks to pre_plug time
> >   
> >> +
> >> +    memory_region_add_subregion(&hpms->mr, addr - hpms->base, mr);  
> > missing vmstate registration?  
> 
> Missed this one: To be called by the caller. Important because e.g. for
> virtio-pmem we don't want this (I assume :) ).
if pmem isn't on shared storage, then We'd probably want to migrate
it as well, otherwise target would experience data loss.
Anyways, I'd just reat it as normal RAM in migration case

> 
> Thanks!
> 
>