exec: Do not resolve subpage in mru_section
This fixes a crash caused by picking the wrong memory region in
address_space_lookup_region seen with client code accessing a device
model that uses alias memory regions. The expensive part of
address_space_lookup_region anyway is phys_page_find; performance-wise
it is okay to repeat the subsequent subpage lookup.
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Message-Id: <
20171114225941.
072707456B5@zero.eik.bme.hu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>