On 26/05/2015 16:00, Alexey Kardashevskiy wrote: > On 05/26/2015 11:48 PM, Paolo Bonzini wrote: >> >> >> 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. > > But when do I get this child property? In memory_region_add_subregion()? > And memory_region_del_subregion() does not do the opposite thing > (unparent)?
In memory_region_init_iommu. >> What is different between the various IOMMU regions, so that you cannot >> create just one? > > There are two DMA windows on the same PCI bus (in hardware too), at > different offset and with a different page size. Why do you need different regions? Why can't you have always the same IOMMU regions, and either: 1) create/destroy an alias to that region 2) change the behavior of the translation function, while keeping a single region? Paolo
