Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751712AbdG1Irz (ORCPT ); Fri, 28 Jul 2017 04:47:55 -0400 Received: from smtp-out4.electric.net ([192.162.216.192]:58521 "EHLO smtp-out4.electric.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751007AbdG1Irx (ORCPT ); Fri, 28 Jul 2017 04:47:53 -0400 From: David Laight To: "'Borislav Petkov'" , Brijesh Singh CC: "linux-efi@vger.kernel.org" , =?utf-8?B?UmFkaW0gS3JjbcOhcg==?= , "kvm@vger.kernel.org" , Fenghua Yu , Matt Fleming , David Howells , "Paul Mackerras" , "H . Peter Anvin" , "Christoph Lameter" , Jonathan Corbet , "x86@kernel.org" , Piotr Luc , Ingo Molnar , Dave Airlie , Laura Abbott , Tom Lendacky , Kees Cook , Arnd Bergmann , Konrad Rzeszutek Wilk , Reza Arbab , "Andy Lutomirski" , Thomas Gleixner , "Tony Luck" , Ard Biesheuvel , "linux-kernel@vger.kernel.org" , Eric Biederman , Tejun Heo , Paolo Bonzini , Andrew Morton , "linuxppc-dev@lists.ozlabs.org" , "Kirill A . Shutemov" , Lu Baolu Subject: RE: [RFC Part1 PATCH v3 07/17] x86/mm: Include SEV for encryption memory attribute changes Thread-Topic: [RFC Part1 PATCH v3 07/17] x86/mm: Include SEV for encryption memory attribute changes Thread-Index: AQHTBukUaCN63Dxfj0uT+W4+/F/DSKJo7inw Date: Fri, 28 Jul 2017 08:47:30 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6DD0045508@AcuExch.aculab.com> References: <20170724190757.11278-1-brijesh.singh@amd.com> <20170724190757.11278-8-brijesh.singh@amd.com> <20170727145841.GG28553@nazgul.tnic> In-Reply-To: <20170727145841.GG28553@nazgul.tnic> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.202.99.200] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-Outbound-IP: 156.67.243.126 X-Env-From: David.Laight@ACULAB.COM X-Proto: esmtps X-Revdns: X-HELO: AcuExch.aculab.com X-TLS: TLSv1:AES128-SHA:128 X-Authenticated_ID: X-PolicySMART: 3396946, 3397078 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id v6S8m5B1027176 Content-Length: 1533 Lines: 45 From: Borislav Petkov > Sent: 27 July 2017 15:59 > On Mon, Jul 24, 2017 at 02:07:47PM -0500, Brijesh Singh wrote: > > From: Tom Lendacky > > > > The current code checks only for sme_active() when determining whether > > to perform the encryption attribute change. Include sev_active() in this > > check so that memory attribute changes can occur under SME and SEV. > > > > Signed-off-by: Tom Lendacky > > Signed-off-by: Brijesh Singh > > --- > > arch/x86/mm/pageattr.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c > > index dfb7d65..b726b23 100644 > > --- a/arch/x86/mm/pageattr.c > > +++ b/arch/x86/mm/pageattr.c > > @@ -1781,8 +1781,8 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) > > unsigned long start; > > int ret; > > > > - /* Nothing to do if the SME is not active */ > > - if (!sme_active()) > > + /* Nothing to do if SME and SEV are not active */ > > + if (!sme_active() && !sev_active()) > > This is the second place which does > > if (!SME && !SEV) > > I wonder if, instead of sprinking those, we should have a > > if (mem_enc_active()) > > or so which unifies all those memory encryption logic tests and makes > the code more straightforward for readers who don't have to pay > attention to SME vs SEV ... If any of the code paths are 'hot' it would make sense to be checking a single memory location. David