Re: [Qemu-arm] [RFC 6/7] hw: arm: virt: register reserved IOVA region

[Pavel Fedin]

 Hello!

> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 3839c68..7eaf8be 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -125,6 +125,7 @@ static const MemMapEntry a15memmap[] = {
>      [VIRT_GPIO] =               { 0x09030000, 0x00001000 },
>      [VIRT_SECURE_UART] =        { 0x09040000, 0x00001000 },
>      [VIRT_MMIO] =               { 0x0a000000, 0x00000200 },
> +    [VIRT_RESERVED] =           { 0x0be00000, 0x00100000 },

 Looks like with this approach we would need to add this to all machine models 
which make use of PCI. But is it a good idea? As far
as i understand, the only requirement for this region is not to clash with 
guest RAM addresses. So, can we instead have some code,
which automatically finds some place, based on the size? For now we hardcode 
the size to 0x00100000, but in future we could query
the host for the size, because it's still host's MSI controller.

Kind regards,
Pavel Fedin
Senior Engineer
Samsung Electronics Research center Russia