From a security PoV, the kernel should never return uncleared memory to (at least unprivileged) user space. This series seems like a big step in that direction.
Well please take a look at the MAP_UNINITIALIZED flag for mmap(). We even have the functionality to return uninitialized system memory when the kernel compile option for this is set since this is an important optimization for many use cases.
Regards,
Christian.
