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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 0D0BBC43603 for ; Fri, 13 Dec 2019 04:05:41 +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 D0AEB2077B for ; Fri, 13 Dec 2019 04:05:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0AEB2077B 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]:40542 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifcCy-0007xP-2N for qemu-devel@archiver.kernel.org; Thu, 12 Dec 2019 23:05:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41282) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifcCA-0007Qf-MV for qemu-devel@nongnu.org; Thu, 12 Dec 2019 23:04:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ifcC9-0004pk-MZ for qemu-devel@nongnu.org; Thu, 12 Dec 2019 23:04:50 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:5516) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ifcC9-0004oD-Ef for qemu-devel@nongnu.org; Thu, 12 Dec 2019 23:04:49 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xBD42BM7023040 for ; Thu, 12 Dec 2019 23:04:48 -0500 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2wuswnengj-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 12 Dec 2019 23:04:47 -0500 Received: from localhost by e06smtp03.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) Fri, 13 Dec 2019 04:04:42 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xBD44fpa42532986 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Dec 2019 04:04:41 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B796E4C04A; Fri, 13 Dec 2019 04:04:41 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 65D9C4C040; Fri, 13 Dec 2019 04:04:40 +0000 (GMT) Received: from in.ibm.com (unknown [9.85.92.59]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Fri, 13 Dec 2019 04:04:40 +0000 (GMT) Date: Fri, 13 Dec 2019 09:34:38 +0530 From: Bharata B Rao To: Greg Kurz Subject: Re: [PATCH v2 ppc-for-5.0 2/2] ppc/spapr: Support reboot of secure pseries guest References: <20191212055059.9399-1-bharata@linux.ibm.com> <20191212055059.9399-3-bharata@linux.ibm.com> <20191212132723.5fdfee47@bahia.tlslab.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191212132723.5fdfee47@bahia.tlslab.ibm.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-TM-AS-GCONF: 00 x-cbid: 19121304-0012-0000-0000-000003745172 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19121304-0013-0000-0000-000021B02F9F Message-Id: <20191213040438.GC28362@in.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-12-12_08:2019-12-12,2019-12-12 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 priorityscore=1501 malwarescore=0 spamscore=0 mlxscore=0 adultscore=0 lowpriorityscore=0 suspectscore=0 mlxlogscore=999 bulkscore=0 phishscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912130032 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] 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: , Reply-To: bharata@linux.ibm.com Cc: Alexey Kardashevskiy , linuxram@us.ibm.com, qemu-devel@nongnu.org, paulus@ozlabs.org, qemu-ppc@nongnu.org, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, Dec 12, 2019 at 01:27:23PM +0100, Greg Kurz wrote: > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > > index f11422fc41..25e1a3446e 100644 > > --- a/hw/ppc/spapr.c > > +++ b/hw/ppc/spapr.c > > @@ -1597,6 +1597,21 @@ static void spapr_machine_reset(MachineState *machine) > > void *fdt; > > int rc; > > > > + /* > > + * KVM_PPC_SVM_OFF ioctl can fail for secure guests, check and > > + * exit in that case. However check for -ENOTTY explicitly > > + * to ensure that we don't terminate normal guests that are > > + * running on kernels which don't support this ioctl. > > + * > > + * Also, this ioctl returns 0 for normal guests on kernels where > > + * this ioctl is supported. > > + */ > > + rc = kvmppc_svm_off(); > > + if (rc && rc != -ENOTTY) { > > This ioctl can also return -EINVAL if the ultravisor actually failed to move > the guest back to non-secure mode or -EBUSY if a vCPU is still running. I > agree that the former deserve the VM to be terminated. What about the latter ? > Can this happen and if yes, why ? Should we try again as suggested by Alexey ? > Could this reveal a bug in QEMU, in which case we should maybe abort ? We are in machine reset path, so all vcpus are already paused. So we don't expect any vcpus to be running to handle -EBUSY here. Neither do I see any sane recovery path from here. As Alexey mentioned earlier, may be we can just stop the VM? Do vm_stop() with RUN_STATE_PAUSED or some such reason? Regards, Bharata.