Re: [Qemu-devel] [RFC ppc-next PATCH 3/6] memory: add memory_region_to_address()

[Peter Maydell]

On 21 March 2013 10:59, Alexander Graf <address@hidden> wrote:
> On 21.03.2013, at 11:53, Peter Maydell wrote:
>> Check kvm_arm_register_device() in target-arm/kvm.c. Basically
>> the VGIC device model calls this function to say "tell the kernel
>> where this MemoryRegion is in the system address space, when it
>> eventually gets mapped". The code in kvm.c uses the memory system's
>> Notifier API to get a callback when the region is mapped into
>> an address space, which it uses to track the offset in the
>> address space. Finally, we use a machine init notifier so that
>> just before everything finally starts we can make the KVM ioctls
>> to say "here is where everything lives".
>
> Same thing here. The question is how the kvm-vgic code in QEMU
> finds out where it got mapped to. Scott adds this patch to do
> this, but I'd assume you have some other way :)

Hmm? The kvm-vgic code in QEMU doesn't need to know where it
lives. We have to tell the kernel so it can map its bits of
registers in at the right place, that's all.

-- PMM