Re: [Qemu-devel] [PATCH 0/5][RFC] virtio-net: MAC filtering

Paul Brook
2009-01-09T19:27:54Z

> A concern here is the growing size of the virtio-net I/O port space
> config. This series brings it up to 256 bytes with PCI resource
> rounding. The VLAN filter bitmap would increase that by another 512
> bytes, making it 1kB and limiting us to something less than 64 such
> devices per guest. Is anyone worried? Should filter tables live in
> MMIO space for virtio devices? I'll send out the guest side patches for
> virtio-net in a separate thread. Thanks,

This is one reason why IO ports are a reallybad idea. Use memory mapped
register spaces like any other sane system and you won't have a problem.

Paul