Re: [PATCH v8 13/17] vfio-user: handle DMA mappings

[Jag Raman]

> On Apr 25, 2022, at 5:56 AM, Stefan Hajnoczi <stefanha@redhat.com> wrote:
> 
> On Tue, Apr 19, 2022 at 04:44:18PM -0400, Jagannathan Raman wrote:
>> +static void dma_unregister(vfu_ctx_t *vfu_ctx, vfu_dma_info_t *info)
>> +{
>> +    VfuObject *o = vfu_get_private(vfu_ctx);
>> +    AddressSpace *dma_as = NULL;
>> +    MemoryRegion *mr = NULL;
>> +    ram_addr_t offset;
>> +
>> +    mr = memory_region_from_host(info->vaddr, &offset);
>> +    if (!mr) {
>> +        return;
>> +    }
>> +
>> +    dma_as = pci_device_iommu_address_space(o->pci_dev);
>> +
>> +    memory_region_del_subregion(dma_as->root, mr);
>> +
>> +    object_unparent((OBJECT(mr)));
> 
> Where is obj->parent set?

Yeah, it should be object_unref().

Thank you!
--
Jag

> 
> If it is not set then this call is a nop and mr is not freed:
> 
>  void object_unparent(Object *obj)
>  {
>      if (obj->parent) {
>          object_property_del_child(obj->parent, obj);
>      }
>  }