On 12/06/2017 04:19 PM, Kees Cook wrote: > On Wed, Dec 6, 2017 at 1:08 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote: >> On Wed 06-12-17 08:33:37, Rasmus Villemoes wrote: >>> On 2017-12-06 05:50, Michael Ellerman wrote: >>>> Michal Hocko <mhocko@xxxxxxxxxx> 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. >> >> I really give up on the name discussion. I will take whatever the >> majority comes up with. I just do not want this (useful) funtionality >> get bikeched to death. > > Yup, I really want this to land too. What do people think of Matthew > Wilcox's MAP_REQUIRED ? MAP_EXACT isn't exact, and dropping "FIXED" > out of the middle seems sensible to me. +1, MAP_REQUIRED does sound like the best one so far, yes. Sorry if I contributed to any excessive bikeshedding. :) thanks, john h > > MIchael, any suggestions with your API hat on? > > -Kees >
