On Mon, May 06, 2019 at 06:30:53PM +0200, Andrey Konovalov wrote: > This patch is a part of a series that extends arm64 kernel ABI to allow to > pass tagged user pointers (with the top byte set to something else other > than 0x00) as syscall arguments. > > mm/gup.c provides a kernel interface that accepts user addresses and > manipulates user pages directly (for example get_user_pages, that is used > by the futex syscall). Since a user can provided tagged addresses, we need > to handle this case. > > Add untagging to gup.c functions that use user addresses for vma lookups. > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
