From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 861D7C282C4 for ; Mon, 4 Feb 2019 12:07:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5827B214DA for ; Mon, 4 Feb 2019 12:07:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729880AbfBDMHZ (ORCPT ); Mon, 4 Feb 2019 07:07:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48476 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728399AbfBDMHZ (ORCPT ); Mon, 4 Feb 2019 07:07:25 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 592718764F; Mon, 4 Feb 2019 12:07:24 +0000 (UTC) Received: from gondolin (ovpn-117-129.ams2.redhat.com [10.36.117.129]) by smtp.corp.redhat.com (Postfix) with ESMTP id CF37C848D8; Mon, 4 Feb 2019 12:07:21 +0000 (UTC) Date: Mon, 4 Feb 2019 13:07:18 +0100 From: Cornelia Huck To: Harald Freudenberger Cc: Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, sebott@linux.ibm.com, oberpar@linux.ibm.com, pmorel@linux.ibm.com, pasic@linux.ibm.com Subject: Re: [PATCH] zcrypt: handle AP Info notification from CHSC SEI command Message-ID: <20190204130718.0fb8cdb3.cohuck@redhat.com> In-Reply-To: <26ec5e3e-de2c-ad82-825d-d20ba52c8937@linux.ibm.com> References: <1548870526-30595-1-git-send-email-akrowiak@linux.ibm.com> <20190131105555.4af6d8ea.cohuck@redhat.com> <2bb57977-bf03-f0c9-abd9-8baa74d31f8a@linux.ibm.com> <20190201153522.4f72cf00.cohuck@redhat.com> <26ec5e3e-de2c-ad82-825d-d20ba52c8937@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Mon, 04 Feb 2019 12:07:25 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 4 Feb 2019 11:15:25 +0100 Harald Freudenberger wrote: > On 01.02.19 15:35, Cornelia Huck wrote: > > On Thu, 31 Jan 2019 18:50:57 -0500 > > Tony Krowiak wrote: > > > >> On 1/31/19 4:55 AM, Cornelia Huck wrote: > >>> On Wed, 30 Jan 2019 12:48:46 -0500 > >>> Tony Krowiak wrote: > >>> Two questions: > >>> - Does the event cover _any_ change to the AP configuration, or can the > >>> periodic scan detect changes that are not signaled? > >> It can detect any change, such as a change to the CRYCB masks. > > Nice. I suppose we can not rely on those messages being generated, > > though, and therefore need to keep the periodic scan... > As you wrote, I am not sure if the ap bus code can rely on this to > cover all changes. For kvm guests I think it is currently not working > as there is no such notification generated at all. So I'd like to > have the periodic scan in place. Yes, and there are bound to be QEMU versions without that support in active use even if this is implemented in the future. But a quicker reaction to changes on real hardware still sounds like a win to me :)