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=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 0CE13C04AB1 for ; Thu, 9 May 2019 11:37:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD6492173C for ; Thu, 9 May 2019 11:37:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726742AbfEILhK (ORCPT ); Thu, 9 May 2019 07:37:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51254 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725963AbfEILhJ (ORCPT ); Thu, 9 May 2019 07:37:09 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C1043C0586DD; Thu, 9 May 2019 11:37:08 +0000 (UTC) Received: from gondolin (dhcp-192-213.str.redhat.com [10.33.192.213]) by smtp.corp.redhat.com (Postfix) with ESMTP id DD5F9643D8; Thu, 9 May 2019 11:37:03 +0000 (UTC) Date: Thu, 9 May 2019 13:37:01 +0200 From: Cornelia Huck To: Halil Pasic Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Martin Schwidefsky , Sebastian Ott , virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman Subject: Re: [PATCH 07/10] s390/airq: use DMA memory for adapter interrupts Message-ID: <20190509133701.3e93299b.cohuck@redhat.com> In-Reply-To: <20190426183245.37939-8-pasic@linux.ibm.com> References: <20190426183245.37939-1-pasic@linux.ibm.com> <20190426183245.37939-8-pasic@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 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Thu, 09 May 2019 11:37:09 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, 26 Apr 2019 20:32:42 +0200 Halil Pasic wrote: > Protected virtualization guests have to use shared pages for airq > notifier bit vectors, because hypervisor needs to write these bits. > > Let us make sure we allocate DMA memory for the notifier bit vectors. > > Signed-off-by: Halil Pasic > --- > arch/s390/include/asm/airq.h | 2 ++ > drivers/s390/cio/airq.c | 18 ++++++++++++++---- > 2 files changed, 16 insertions(+), 4 deletions(-) As an aside, there are some other devices that use adapter interrupts as well (pci, ap, qdio). How does that interact with their needs? Do they continue to work on non-protected virt guests (kvm or z/VM), and can they be accommodated if support for them on protected guests is added in the future? (For some of the indicator bit handling, I suspect millicode takes care of it anyway, but at least for pci, there's some hypervisor action to be aware of.) Also, as another aside, has this been tested with a regular guest under tcg as well? If not, can you provide a branch for quick verification somewhere?