On 02/08/2017 11:02, peng.hao2@xxxxxxxxxx wrote: > >> On 02/08/2017 10:45, peng.hao2@xxxxxxxxxx wrote: >> >>On 02/08/2017 17:24, Peng Hao wrote: >> > coalesced MMIO is async and io port should be sync . I don't need to >> > coalese io port access. > >> Coalesced MMIO access is resolved on the next read from a coalesced MMIO >> address or the next write to a non-coalescecd MMIO address. So it would >> work perfectly for port 0x70. You would have to modify QEMU to split >> the RTC I/O ports into two MemoryRegions. > > ok , it sounds simpler. I will try it. My suggestion is to repurpose the "pad" field of "struct kvm_coalesced_mmio_zone" to be 0 for memory and -1 for I/O. It should be enough for an RFC. Later we can look into how to handle backwards compatibility. Thanks, Paolo
