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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 75674C35DF5 for ; Tue, 25 Feb 2020 12:44:46 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49D2F20637 for ; Tue, 25 Feb 2020 12:44:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49D2F20637 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54514 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6ZZt-0008R2-EA for qemu-devel@archiver.kernel.org; Tue, 25 Feb 2020 07:44:45 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50765) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j6YpZ-0002Xu-Lv for qemu-devel@nongnu.org; Tue, 25 Feb 2020 06:56:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j6YpX-0003eV-EA for qemu-devel@nongnu.org; Tue, 25 Feb 2020 06:56:53 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:12000) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j6YpX-0003bA-6h for qemu-devel@nongnu.org; Tue, 25 Feb 2020 06:56:51 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01PBp5jX019843 for ; Tue, 25 Feb 2020 06:56:50 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ycxcxsrs5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 25 Feb 2020 06:56:49 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 25 Feb 2020 11:56:45 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01PBuhHr44630382 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 25 Feb 2020 11:56:43 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C71EA4C04E; Tue, 25 Feb 2020 11:56:43 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 777D84C040; Tue, 25 Feb 2020 11:56:43 +0000 (GMT) Received: from oc2783563651 (unknown [9.152.224.149]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 25 Feb 2020 11:56:43 +0000 (GMT) Date: Tue, 25 Feb 2020 12:56:41 +0100 From: Halil Pasic To: David Hildenbrand Subject: Re: [PATCH 1/1] s390/ipl: sync back loadparm In-Reply-To: <05f7dcf7-a0c7-8811-6b88-df86d5fa0974@redhat.com> References: <20200224150213.21253-1-pasic@linux.ibm.com> <05f7dcf7-a0c7-8811-6b88-df86d5fa0974@redhat.com> Organization: IBM X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 20022511-0016-0000-0000-000002EA1914 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20022511-0017-0000-0000-0000334D444B Message-Id: <20200225125641.72e8cc86.pasic@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-02-25_03:2020-02-21, 2020-02-25 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 bulkscore=0 impostorscore=0 lowpriorityscore=0 adultscore=0 clxscore=1015 suspectscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 priorityscore=1501 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002250097 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 148.163.156.1 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Thomas Huth , Janosch Frank , Cornelia Huck , qemu-devel@nongnu.org, Christian Borntraeger , qemu-s390x@nongnu.org, Marc Hartmayer , Viktor Mihajlovski , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 25 Feb 2020 10:39:40 +0100 David Hildenbrand wrote: > On 24.02.20 16:02, Halil Pasic wrote: > > We expose loadparm as a r/w machine property, but if loadparm is set by > > the guest via DIAG 308, we don't update the property. Having a > > disconnect between the guest view and the QEMU property is not nice in > > itself, but things get even worse for SCSI, where under certain > > circumstances (see 789b5a401b "s390: Ensure IPL from SCSI works as > > expected" for details) we call s390_gen_initial_iplb() on resets > > effectively overwriting the guest/user supplied loadparm with the stale > > value. > > > > Signed-off-by: Halil Pasic > > Fixes: 7104bae9de "hw/s390x: provide loadparm property for the machine" > > Reported-by: Marc Hartmayer > > Reviewed-by: Janosch Frank > > Reviewed-by: Viktor Mihajlovski > > Tested-by: Marc Hartmayer > > --- > > hw/s390x/ipl.c | 21 +++++++++++++++++++++ > > 1 file changed, 21 insertions(+) > > > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > > index 7773499d7f..97a279c1a5 100644 > > --- a/hw/s390x/ipl.c > > +++ b/hw/s390x/ipl.c > > @@ -538,6 +538,26 @@ static bool is_virtio_scsi_device(IplParameterBlock *iplb) > > return is_virtio_ccw_device_of_type(iplb, VIRTIO_ID_SCSI); > > } > > > > +static void update_machine_ipl_properties(IplParameterBlock *iplb) > > +{ > > + Object *mo = qdev_get_machine(); > > I'd just call this "machine". > I can change that. > > + > > + /* Sync loadparm */ > > + if (iplb->flags & DIAG308_FLAGS_LP_VALID) { > > + char ascii_loadparm[8]; > > + uint8_t *ebcdic_loadparm = iplb->loadparm; > > + int i; > > + > > + for (i = 0; i < 8 && ebcdic_loadparm[i]; i++) { > > + ascii_loadparm[i] = ebcdic2ascii[(uint8_t) ebcdic_loadparm[i]]; > > + } > > + ascii_loadparm[i] = 0; > > + object_property_set_str(mo, ascii_loadparm, "loadparm", NULL); > > + } else { > > + object_property_set_str(mo, "", "loadparm", NULL); > > + } > > &error_abort instead of NULL, we certainly want to know if this would > ever surprisingly fail. IMHO this is a typical assert() situation where one would like to have a fast and obvious failure when testing, but not in production. AFAIU the guest can trigger this code at any time, and crashing the whole (production) system seems a bit heavy handed to me. The setter should only fail if something is buggy. But if the majority says &error_abort I can certainly do. Other opinions? > > > +} > > + > > void s390_ipl_update_diag308(IplParameterBlock *iplb) > > { > > S390IPLState *ipl = get_ipl_device(); > > @@ -545,6 +565,7 @@ void s390_ipl_update_diag308(IplParameterBlock *iplb) > > ipl->iplb = *iplb; > > ipl->iplb_valid = true; > > ipl->netboot = is_virtio_net_device(iplb); > > + update_machine_ipl_properties(iplb); > > } > > > > Somewhat I dislike this manual syncing (and converting back and forth), > but there seems to be no easy way around it. > I share your sentiment. Regards, Halil