virt: acrn: obtain pa from VMA with PFNMAP flag

virt: acrn: obtain pa from VMA with PFNMAP flag

 acrn_vm_ram_map can't pin the user pages with VM_PFNMAP flag
 by calling get_user_pages_fast(), the PA(physical pages)
 may be mapped by kernel driver and set PFNMAP flag.

 This patch fixes logic to setup EPT mapping for PFN mapped RAM region
 by checking the memory attribute before adding EPT mapping for them.

Fixes: 88f537d5e8dd ("virt: acrn: Introduce EPT mapping management")
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20220228022212.419406-1-yonghua.huang@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>