From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yu-cheng Yu Subject: Re: [RFC PATCH v2 08/27] mm: Introduce VM_SHSTK for shadow stack memory Date: Wed, 11 Jul 2018 09:15:01 -0700 Message-ID: <1531325701.13297.32.camel@intel.com> References: <20180710222639.8241-1-yu-cheng.yu@intel.com> <20180710222639.8241-9-yu-cheng.yu@intel.com> <20180711083412.GP2476@hirez.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20180711083412.GP2476@hirez.programming.kicks-ass.net> Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Ravi V. Shan List-Id: linux-api@vger.kernel.org On Wed, 2018-07-11 at 10:34 +0200, Peter Zijlstra wrote: > On Tue, Jul 10, 2018 at 03:26:20PM -0700, Yu-cheng Yu wrote: > > > > VM_SHSTK indicates a shadow stack memory area. > > > > A shadow stack PTE must be read-only and dirty.  For non shadow > > stack, we use a spare bit of the 64-bit PTE for dirty.  The PTE > > changes are in the next patch. > This doesn't make any sense.. the $subject and the patch seem > completely > unrelated to this Changelog. I was trying to say why this is only defined for 64-bit.  I will fix it. Yu-cheng