Re: [PATCH RFC] bpf: Add support for reading user pointers

[Joel Fernandes]

On Fri, May 03, 2019 at 03:54:26PM +0200, Peter Zijlstra wrote:
> On Fri, May 03, 2019 at 09:49:35AM -0400, Joel Fernandes wrote:
> > In
> > particular, we learnt with extensive discussions that user/kernel pointers
> > are not necessarily distinguishable purely based on their address.
> 
> This is correct; a number of architectures have a completely separate
> user and kernel address space. Much like how the old i386 4G:4G patches
> worked.

Thanks Peter for confirming.