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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,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 85CBBC04AB3 for ; Mon, 27 May 2019 10:53:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 625302133F for ; Mon, 27 May 2019 10:53:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726197AbfE0Kxb (ORCPT ); Mon, 27 May 2019 06:53:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41840 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725814AbfE0Kxb (ORCPT ); Mon, 27 May 2019 06:53:31 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 41B4E307D855; Mon, 27 May 2019 10:53:31 +0000 (UTC) Received: from gondolin (ovpn-204-109.brq.redhat.com [10.40.204.109]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3EFDD5D704; Mon, 27 May 2019 10:53:23 +0000 (UTC) Date: Mon, 27 May 2019 12:53:20 +0200 From: Cornelia Huck To: Michael Mueller Cc: KVM Mailing List , Linux-S390 Mailing List , Sebastian Ott , Heiko Carstens , Halil Pasic , 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 , Pierre Morel Subject: Re: [PATCH v2 4/8] s390/airq: use DMA memory for adapter interrupts Message-ID: <20190527125320.7540049a.cohuck@redhat.com> In-Reply-To: <20190523162209.9543-5-mimu@linux.ibm.com> References: <20190523162209.9543-1-mimu@linux.ibm.com> <20190523162209.9543-5-mimu@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 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Mon, 27 May 2019 10:53:31 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, 23 May 2019 18:22:05 +0200 Michael Mueller wrote: > From: Halil Pasic > > 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 by > replacing the kmem_cache with a dma_cache and kalloc() with > cio_dma_zalloc(). > > Signed-off-by: Halil Pasic > --- > arch/s390/include/asm/airq.h | 2 ++ > drivers/s390/cio/airq.c | 32 ++++++++++++++++++++------------ > drivers/s390/cio/cio.h | 2 ++ > drivers/s390/cio/css.c | 1 + > 4 files changed, 25 insertions(+), 12 deletions(-) (...) > diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c > index 789f6ecdbbcc..f09521771a32 100644 > --- a/drivers/s390/cio/css.c > +++ b/drivers/s390/cio/css.c > @@ -1173,6 +1173,7 @@ static int __init css_bus_init(void) > goto out_unregister; > } > cio_dma_pool_init(); > + airq_init(); > css_init_done = 1; > > /* Enable default isc for I/O subchannels. */ Not directly related to this patch (I don't really have any comment here), but I started looking at the code again and now I'm wondering about chsc. I think it came up before, but I can't remember if chsc needed special treatment... Anyway, css_bus_init() uses some chscs early (before cio_dma_pool_init), so we could not use the pools there, even if we wanted to. Do chsc commands either work, or else fail benignly on a protected virt guest?