ACRN does not support the variable range vMTRR. The default
memory type of vMTRR is UC. With this vMTRR emulation guest VM
such as Linux refuses to map the MMIO address space as WB. In
order to get better performance SHM BAR of ivshmem is mapped
with PAT ignored and memory type of SHM BAR is fixed to WB.
Tracked-On: #6389
Signed-off-by: Jian Jun Chen <jian.jun.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
dc77ef9e52