From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Kirill A. Shutemov" Subject: Re: [PATCH 4/6] x86/kasan: Prepare clear_pgds() to switch to Date: Fri, 24 Mar 2017 12:07:57 +0300 Message-ID: <20170324090757.inkuvayf5t7g73po@node.shutemov.name> References: <20170317185515.8636-1-kirill.shutemov@linux.intel.com> <20170317185515.8636-5-kirill.shutemov@linux.intel.com> <218853b4-3498-dab9-d1e9-02caed4d9322@virtuozzo.com> <20170322073136.GC13904@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wm0-f49.google.com ([74.125.82.49]:38390 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756416AbdCXJIB (ORCPT ); Fri, 24 Mar 2017 05:08:01 -0400 Received: by mail-wm0-f49.google.com with SMTP id t189so7856748wmt.1 for ; Fri, 24 Mar 2017 02:08:00 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20170322073136.GC13904@gmail.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Ingo Molnar Cc: Andrey Ryabinin , "Kirill A. Shutemov" , Linus Torvalds , Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , Arnd Bergmann , "H. Peter Anvin" , Andi Kleen , Dave Hansen , Andy Lutomirski , Michal Hocko , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dmitry Vyukov On Wed, Mar 22, 2017 at 08:31:36AM +0100, Ingo Molnar wrote: > * Andrey Ryabinin wrote: > > On 03/17/2017 09:55 PM, Kirill A. Shutemov wrote: > > > With folded p4d, pgd_clear() is nop. Change clear_pgds() to use > > > p4d_clear() instead. > > > > > > > You could probably just use set_pgd(pgd_offset_k(start), __pgd(0)); instead of pgd_clear() > > as we already do in arm64. > > It's basically pgd_clear() except it's not a nop wih p4d folded. > > Makes sense. Kirill, if you agree, mind spinning a v2 patch? I can re-spin, if you want. But honestly, I don't think such constructs help readability. -- Kirill A. Shutemov