Re: [Qemu-ppc] [PATCH qemu v7 06/14] spapr_iommu: Introduce "enabled" state for TCE table

[Paolo Bonzini]

On 26/05/2015 15:42, Alexey Kardashevskiy wrote:
> 
> 
> The next patch of this patchset changes:
> spapr_tce_table_do_enable()
>     memory_region_init_iommu(&iommu)
>     memory_region_add_subregion(&root, &iommu)
> 
> spapr_tce_table_disable()
>     memory_region_del_subregion(&root, &iommu)
>     object_unref(&iommu)
> 
> These spapr_tce_xxx are called by request from the guest. &root is a
> container and exists as long as sPAPRTCETable exists.
> 
> Where do I get a leaking child property here?

When you unref iommu and not unparent it.  The next
memory_region_init_iommu creates a second child property, and the first
is gone.

What is different between the various IOMMU regions, so that you cannot
create just one?

Paolo