On 2017-12-06 05:50, Michael Ellerman wrote: > Michal Hocko <mho...@kernel.org> writes: > >> On Wed 29-11-17 14:25:36, Kees Cook wrote: >> It is safe in a sense it doesn't perform any address space dangerous >> operations. mmap is _inherently_ about the address space so the context >> should be kind of clear. > > So now you have to define what "dangerous" means. > >>> MAP_FIXED_UNIQUE >>> MAP_FIXED_ONCE >>> MAP_FIXED_FRESH >> >> Well, I can open a poll for the best name, but none of those you are >> proposing sound much better to me. Yeah, naming sucks...
I also don't like the _SAFE name - MAP_FIXED in itself isn't unsafe [1], but I do agree that having a way to avoid clobbering (parts of) an existing mapping is quite useful. Since we're bikeshedding names, how about MAP_FIXED_EXCL, in analogy with the O_ flag. [1] I like the analogy between MAP_FIXED and dup2 made in <stackoverflow.com/questions/28575893>. Rasmus
