On Wed, Nov 25, 2020 at 11:22:02AM +0200, Mike Rapoport wrote: > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > On arm64, set_direct_map_*() functions may return 0 without actually > changing the linear map. This behaviour can be controlled using kernel > parameters, so we need a way to determine at runtime whether calls to > set_direct_map_invalid_noflush() and set_direct_map_default_noflush() have > any effect. > > Extend set_memory API with can_set_direct_map() function that allows > checking if calling set_direct_map_*() will actually change the page table, > replace several occurrences of open coded checks in arm64 with the new > function and provide a generic stub for architectures that always modify > page tables upon calls to set_direct_map APIs. > > Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
