Il 03/06/2013 11:58, Peter Maydell ha scritto: > On 3 June 2013 10:40, Paolo Bonzini <pbonz...@redhat.com> wrote: >> Il 03/06/2013 11:22, Peter Maydell ha scritto: >>> arm11mpcore.c does this: >>> sysbus_init_mmio(dev, sysbus_mmio_get_region(s->priv, 0)); >>> which I suspect will assert with your patches. >> >> Thanks for the pointer. All other occurrences of >> sys_bus_mmio_get_region are either in non-qdevified OMAP code, or they >> do what I said in my patch. >> >> I'll fix a11mpcore to use an alias. > > Why? There is no need to -- this should be a perfectly > reasonable use of MemoryRegion*s. If your reference counting > code can't deal with it you need to fix the reference > counting code.
It can: 1) I could set the owner to NULL before calling the sysbus_init_mmio; 2) I could add a variant of sysbus_init_mmio that doesn't set the owner; 3) I could skip setting the owner for sysbus altogether, since it is only strictly required for unpluggable devices. What I cannot do is having two owners, where each ref/unref pair will ref/unref both objects. I think you agree that it is overkill. However, I think there is worth in preserving the chain through either containment or aliasing. From the nesting point of view, realview_mpcore is exposing the region. From the implementor point of view, arm_gic is implementing the region (and arm_gic is the one that would be ref/unref'd at execution time). In either case, arm11mpcore_priv is not what you want to see. Its presence is just an implementation detail of realview_mpcore. Paolo
