On Fri, Dec 23, 2022 at 10:24:25AM +0000, Lorenzo Stoakes wrote: > Might it be worth adding a specific vmap mask that explicitly indicates what > flags are permissible on vmap()? Then this could become e.g.:- > > if (WARN_ON_ONCE(flags & ~VM_VMAP_PERMITTED_MASK)) > return NULL; > > And would be self-documenting as to why we are disallowing flags (i.e. they are > not part of the permitted vmap mask). That's probably a good idea. It might need some time to audit for use of all the flags, though.