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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 8AAFDC43382 for ; Tue, 25 Sep 2018 13:26:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 315372086E for ; Tue, 25 Sep 2018 13:26:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 315372086E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729206AbeIYTd7 (ORCPT ); Tue, 25 Sep 2018 15:33:59 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40728 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729152AbeIYTd7 (ORCPT ); Tue, 25 Sep 2018 15:33:59 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w8PDOnmx029060 for ; Tue, 25 Sep 2018 09:26:24 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2mqm82w6v3-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 25 Sep 2018 09:26:23 -0400 Received: from localhost by e34.co.us.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 Sep 2018 07:26:19 -0600 Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w8PDQG7B55902330 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 25 Sep 2018 06:26:16 -0700 Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0D75E6E04C; Tue, 25 Sep 2018 07:26:16 -0600 (MDT) Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3EBEE6E053; Tue, 25 Sep 2018 07:26:13 -0600 (MDT) Received: from oc8043147753.ibm.com (unknown [9.80.207.102]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 25 Sep 2018 07:26:13 -0600 (MDT) Subject: Re: [PATCH v10 24/26] KVM: s390: device attrs to enable/disable AP interpretation To: David Hildenbrand , Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com, frankja@linux.ibm.com References: <1536781396-13601-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1536781396-13601-25-git-send-email-akrowiak@linux.vnet.ibm.com> <9263b698-1827-1b7f-28bf-75b44657dea2@redhat.com> <18a21cda-1da9-3bfb-7b34-80415b5457f9@linux.ibm.com> <172560fb-2c54-ea43-3401-f108cf2a0595@redhat.com> <1c0c5a2e-3ef4-e5f5-52b8-7aeddca1f472@linux.ibm.com> <62f0cacc-8338-9370-a4dc-12f793214c48@redhat.com> From: Tony Krowiak Date: Tue, 25 Sep 2018 09:26:12 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <62f0cacc-8338-9370-a4dc-12f793214c48@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 18092513-0016-0000-0000-000009346CC3 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009769; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000267; SDB=6.01093445; UDB=6.00565148; IPR=6.00873482; MB=3.00023497; MTD=3.00000008; XFM=3.00000015; UTC=2018-09-25 13:26:22 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18092513-0017-0000-0000-0000407A39C4 Message-Id: <889157be-c209-8938-ccb2-240ae5249cda@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-09-25_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1809250136 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/25/2018 03:32 AM, David Hildenbrand wrote: > On 24/09/2018 20:42, Tony Krowiak wrote: >> On 09/24/2018 12:25 PM, Tony Krowiak wrote: >>> On 09/24/2018 07:23 AM, David Hildenbrand wrote: >> >> (...) >> >>>> Will you also fixup this patch to expose KVM_S390_VM_CRYPTO_ENABLE_APIE >>>> only if supported by HW? (ap_instructions_available) >>> >>> Given that this patch DOES expose KVM_S390_VM_CRYPTO_ENABLE_APIE only if >>> supported by HW, I assume you are talking about >>> KVM_S390_VM_CRYPTO_DISABLE_APIE. I didn't check >>> ap_instructions_available() for disabling APIE because I didn't >>> think it necessary given that ECA.28 will be set to 0 (intercept) by >>> default, whether AP instructions are installed or not; so why not allow >>> disabling apie. I suppose from the perspective of consistency, since the >>> kvm_s390_vm_has_attr() function checks ap_instructions_available() for >>> both attributes, then it probably makes sense to add that check to >>> KVM_S390_VM_CRYPTO_DISABLE_APIE here. Then again, we could make a change >>> in ap_instructions_available() to allow KVM_S390_VM_CRYPTO_DISABLE_APIE >>> regardless of whether AP instructions are available. It boils down to >>> whether APIE needs to be dynamically disabled at some point when it has >>> been enabled. The only case I can think of where that may be necessary >>> is if a guest is migrated to a system without AP instructions. I don't >>> think that can happen and may even be protected against precisely >>> because the VM attributes won't be available on the target system due to >>> no AP instructions. What say you? >>> >> David, >> >> I'm sorry, I misinterpreted what you were asking for. Check out the >> fixup! patch below and let me know if that is what you are looking for. >> If so, I will integrate that change and post v11 tomorrow (Tuesday 9/24). >> >> -----------------------------------8<----------------------------------- >> >> From: Tony Krowiak >> Date: Mon, 24 Sep 2018 14:18:37 -0400 >> Subject: [FIXUP v10] fixup! KVM: s390: device attrs to enable/disable AP >> interpretation >> >> --- >> arch/s390/kvm/kvm-s390.c | 9 ++++++++- >> 1 file changed, 8 insertions(+), 1 deletion(-) >> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index 6654bb1fc26a..a528558baa78 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -901,6 +901,10 @@ static int kvm_s390_vm_set_crypto(struct kvm *kvm, >> struct kvm_device_attr *attr) >> kvm->arch.crypto.apie = 1; >> break; >> case KVM_S390_VM_CRYPTO_DISABLE_APIE: >> + if (!ap_instructions_available()) { >> + mutex_unlock(&kvm->lock); >> + return -EOPNOTSUPP; >> + } >> kvm->arch.crypto.apie = 0; >> break; >> default: >> @@ -1509,9 +1513,11 @@ static int kvm_s390_vm_has_attr(struct kvm *kvm, >> struct kvm_device_attr *attr) >> case KVM_S390_VM_CRYPTO_ENABLE_DEA_KW: >> case KVM_S390_VM_CRYPTO_DISABLE_AES_KW: >> case KVM_S390_VM_CRYPTO_DISABLE_DEA_KW: >> + ret = 0; >> + break; >> case KVM_S390_VM_CRYPTO_ENABLE_APIE: >> case KVM_S390_VM_CRYPTO_DISABLE_APIE: >> - ret = 0; >> + ret = ap_instructions_available(); > > Just a little remark, I guess we want to report 0 if available and > -ENXIO if not. That makes sense ... I'll fix it. >