On 11/08/2017 03:56 PM, Haozhong Zhang wrote:
Some reserved pages, such as those from NVDIMM DAX devices, are not for MMIO, and can be mapped with cached memory type for better performance. However, the above check misconceives those pages as MMIO. Because KVM maps MMIO pages with UC memory type, the performance of guest accesses to those pages would be harmed. Therefore, we check the host memory type in addition and only treat UC/UC- pages as MMIO.
Reviewed-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxx>
