Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753362AbcCGTUF (ORCPT <rfc822;w@1wt.eu>);
	Mon, 7 Mar 2016 14:20:05 -0500
Received: from shards.monkeyblade.net ([149.20.54.216]:53261 "EHLO
	shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1753175AbcCGTT4 (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 7 Mar 2016 14:19:56 -0500
Date: Mon, 07 Mar 2016 14:19:50 -0500 (EST)
Message-Id: <20160307.141950.2225098078054843052.davem@davemloft.net>
To: luto@amacapital.net
Cc: khalid.aziz@oracle.com, corbet@lwn.net, akpm@linux-foundation.org,
        dingel@linux.vnet.ibm.com, bob.picco@oracle.com,
        kirill.shutemov@linux.intel.com, aneesh.kumar@linux.vnet.ibm.com,
        aarcange@redhat.com, arnd@arndb.de, sparclinux@vger.kernel.org,
        rob.gardner@oracle.com, mhocko@suse.cz, chris.hyser@oracle.com,
        richard@nod.at, vbabka@suse.cz, koct9i@gmail.com, oleg@redhat.com,
        gthelen@google.com, jack@suse.cz, xiexiuqi@huawei.com,
        Vineet.Gupta1@synopsys.com, luto@kernel.org, ebiederm@xmission.com,
        bsegall@google.com, geert@linux-m68k.org, dave@stgolabs.net,
        adobriyan@gmail.com, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-arch@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [PATCH v2] sparc64: Add support for Application Data Integrity
 (ADI)
From: David Miller <davem@davemloft.net>
In-Reply-To: <CALCETrU5NCzh3b7We8903G0_Tm-oycgP3+gS9fG+vC_rdgTddw@mail.gmail.com>
References: <CALCETrXN43nT4zq2MpO90VrgK3k+DKHjOHWf7iOhS7TSBmdCPQ@mail.gmail.com>
	<56DDC6E0.4000907@oracle.com>
	<CALCETrU5NCzh3b7We8903G0_Tm-oycgP3+gS9fG+vC_rdgTddw@mail.gmail.com>
X-Mailer: Mew version 6.6 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO)
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 07 Mar 2016 11:19:55 -0800 (PST)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 384
Lines: 9

From: Andy Lutomirski <luto@amacapital.net>
Date: Mon, 7 Mar 2016 10:49:57 -0800

> What data structure or structures changes when this stxa instruction happens?

An internal table, maintained by the CPU and/or hypervisor, and if in physical
addresses then in a region which is only accessible by the hypervisor.

The table is not accessible by the kernel at all via loads or stores.