On Mon, 19 Feb 2018, Balbir Singh wrote:
> Good point, although I think the acquire_* function itself may be called > from a higher layer with the mmap_sem always held. I wonder if we need > barriers around get and put mmio_atsd_reg. I agree with the need for memory barriers. FWIW, page tables can be invalidated without mmap_sem being held, for example by unmap_mapping_range.
