On Thu, Jan 4, 2018 at 10:17 AM, Alexei Starovoitov
<[email protected]> wrote:
>
> Clearly Paul's approach to retpoline without lfence is faster.
> I'm guessing it wasn't shared with amazon/intel until now and
> this set of patches going to adopt it, right?
>
> Paul, could you share a link to a set of alternative gcc patches
> that do retpoline similar to llvm diff ?
What is the alternative approach? Is it literally just doing a
call 1f
1: mov real_target,(%rsp)
ret
on the assumption that the "ret" will always just predict to that "1"
due to the call stack?
Linus
