On Thu, 17 Nov 2016, Michael Ellerman wrote: > Currently ZERO_OR_NULL_PTR() uses a trick of doing a single check that > x <= ZERO_SIZE_PTR, and ignoring the fact that it also matches 1-15.
Well yes that was done so we do not add too many branches all over the kernel..... > That no longer really works once we add the poison delta, so split it > into two checks. Assign x to a temporary to avoid evaluating it > twice (suggested by Kees Cook). And now you are doing just that.
