Subject: Re: [RFC PATCH v3 04/12] Validate r1 value before going to host kernel in virtual mode.

From: Benjamin Herrenschmidt <[email-masked]>
Date: Mon, 09 Sep 2013 19:26:35 +1000

On Mon, 2013-09-09 at 15:29 +1000, Paul Mackerras wrote:
> Are we guaranteed that Sapphire will keep the stack pointer positive
> at all times?  (More a question for Ben H than you.)

Good point, we *might* eventually set the top bit..

Ben.