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Date: Mon, 08 Jun 2015 17:30:20 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [RFC v2 4/6] hostmem: return recreated
 MemoryRegion if current can't be reused
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To: Igor Mammedov <imammedo@redhat.com>, qemu-devel@nongnu.org
Cc: mst@redhat.com



On 08/06/2015 17:19, Igor Mammedov wrote:
>  MemoryRegion *
>  host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
>  {
> +    UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(backend);
> +
> +    if (memory_region_is_hva_mapped(&backend->mr)) {
> +        object_unparent(OBJECT(&backend->mr));
> +        ucc->complete(USER_CREATABLE(backend), errp);
> +    }

I'm not sure I understand this, and the commit message... doesn't help.

Is it for the case where you unplug memory and then reuse the old
backend?  Can we just outlaw this, forcing each memory backend to be
used only once?

Paolo