On Fri, Dec 23, 2022 at 03:03:12PM +0100, Christoph Hellwig wrote: > 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. Perhaps leave that for a later patch (I could take a look as well), but in the meantime might be worth adding a quick comment here indicating why the flag is prohibited?
