From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f200.google.com (mail-pg1-f200.google.com [209.85.215.200]) by kanga.kvack.org (Postfix) with ESMTP id 672E98E0001 for ; Mon, 10 Sep 2018 22:46:45 -0400 (EDT) Received: by mail-pg1-f200.google.com with SMTP id s11-v6so11626711pgv.9 for ; Mon, 10 Sep 2018 19:46:45 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTPS id d68-v6si20745390pfj.311.2018.09.10.19.46.44 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 10 Sep 2018 19:46:44 -0700 (PDT) Date: Mon, 10 Sep 2018 19:46:57 -0700 From: Alison Schofield Subject: Re: [RFC 10/12] x86/pconfig: Program memory encryption keys on a system-wide basis Message-ID: <20180911024657.GC1732@alison-desk.jf.intel.com> References: <0947e4ad711e8b7c1f581a446e808f514620b49b.1536356108.git.alison.schofield@intel.com> <73c60d4f8a953476f1e29aaccbeb7f732c209190.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <73c60d4f8a953476f1e29aaccbeb7f732c209190.camel@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: "Sakkinen, Jarkko" Cc: "tglx@linutronix.de" , "dhowells@redhat.com" , "Shutemov, Kirill" , "keyrings@vger.kernel.org" , "jmorris@namei.org" , "Huang, Kai" , "linux-mm@kvack.org" , "linux-security-module@vger.kernel.org" , "x86@kernel.org" , "hpa@zytor.com" , "mingo@redhat.com" , "Hansen, Dave" , "Nakajima, Jun" On Mon, Sep 10, 2018 at 11:24:20AM -0700, Sakkinen, Jarkko wrote: > On Fri, 2018-09-07 at 15:38 -0700, Alison Schofield wrote: > > The kernel manages the MKTME (Multi-Key Total Memory Encryption) Keys > > as a system wide single pool of keys. The hardware, however, manages > > the keys on a per physical package basis. Each physical package > > maintains a key table that all CPU's in that package share. > > > > In order to maintain the consistent, system wide view that the kernel > > requires, program all physical packages during a key program request. > > > > Signed-off-by: Alison Schofield > > Just kind of checking that are you talking about multiple cores in > a single package or really multiple packages? System wide pool. System has multiple packages. Packages have multiple CPU's. The hardware KEY TABLE is per package. I need that per package KEY TABLE to be the same in every package across the system. So, I pick one 'lead' CPU in each package to program that packages KEY TABLE. (BTW - I'm going to look into Kai's suggestion to move the system wide view of this key programming into the key service. Not sure if that's a go.) > > /Jarkko