On Mon, Apr 25, 2022 at 10:43:45AM +0200, Jan Beulich wrote: > When a page table ends up with all contiguous entries (including all > identical attributes), it can be replaced by a superpage entry at the > next higher level. The page table itself can then be scheduled for > freeing. > > The adjustment to LEVEL_MASK is merely to avoid leaving a latent trap > for whenever we (and obviously hardware) start supporting 512G mappings. > > Signed-off-by: Jan Beulich <[email protected]> > Reviewed-by: Kevin Tian <[email protected]>
Like on the AMD side, I wonder whether you can get away with only doing a cache flush for the last (highest level) PTE, as the lower ones won't be reachable anyway, as the page-table is freed. Then the flush could be done outside of the locked region. The rest LGTM. Thanks, Roger.
