On Fri, Oct 12, 2018 at 12:02:56AM +0300, Cyrill Gorcunov wrote: > On Thu, Oct 11, 2018 at 11:56:01PM +0300, Alexey Dobriyan wrote: > > > > As the comment in the beginning says this test is specifically for addresss 0. > > Maybe it should be ifdeffed with __arm__ then. > > Is there some other reason than allocating non-mergable VMA? IIRC the reason is to test address 0 as it is effectively banned for userspace so if it will be broken, it will be broken silently for a long time. As for "unmergeable" libc here doesn't map /dev/zero. I know how to avoid even theoretical breakage by creating binaries by hand but it will be probably too much.
