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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id EEAB7C433F5 for ; Thu, 19 May 2022 13:54:25 +0000 (UTC) Received: from localhost ([::1]:58364 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nrgbg-0005qC-Uo for qemu-devel@archiver.kernel.org; Thu, 19 May 2022 09:54:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39906) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrgay-0005Ak-A9; Thu, 19 May 2022 09:53:40 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:41180) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrgaw-0000oI-A0; Thu, 19 May 2022 09:53:40 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 24JDHTvN005967; Thu, 19 May 2022 13:53:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=ol55uRCvYWgWyBl/03RigGLhvv0+9Dp3mqx4dOkYdqQ=; b=AzbVeVfiH1aCfxZAhCLkwVC/e+fZqRSmORMLpfrYw4btBjuv0l+ArmZdJ/Yw/yZskKwZ 5lZSSWXS60MoBqbwv9QiktSRcv0o1wTFHBJTFBBEMnCtwpTAK8xE62Y4/Gc9Wf7p0ddO NguHDPTNp56+SH+59m5t+rSK5r6lvSELBUAGC3AtFsisBJSpPtd/xzKTP1T0oCzLBnnd AqBWzvKwjLOkoGXOGekh8HHPCi6XfWCErSGlef9Q1k2vcXyYdkHmqYp6Gcwlv1efQB6/ D75ZwY9dOWeDxqk6kFJc3ioYRTW8rFZgZbLs6PGP8+dhY6iHCOeZIpJEpUClq4rH7p3y 1Q== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3g5pn08vnq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 May 2022 13:53:33 +0000 Received: from m0098410.ppops.net (m0098410.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 24JDrWMk010381; Thu, 19 May 2022 13:53:32 GMT Received: from ppma01fra.de.ibm.com (46.49.7a9f.ip4.static.sl-reverse.com [159.122.73.70]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3g5pn08vmw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 May 2022 13:53:32 +0000 Received: from pps.filterd (ppma01fra.de.ibm.com [127.0.0.1]) by ppma01fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 24JDpAwR021419; Thu, 19 May 2022 13:53:30 GMT Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by ppma01fra.de.ibm.com with ESMTP id 3g2428x2us-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 19 May 2022 13:53:30 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 24JDrQQN46072118 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 19 May 2022 13:53:26 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D8DAAAE045; Thu, 19 May 2022 13:53:26 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F1271AE051; Thu, 19 May 2022 13:53:25 +0000 (GMT) Received: from [9.171.37.72] (unknown [9.171.37.72]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 19 May 2022 13:53:25 +0000 (GMT) Message-ID: <384df8c6-4309-17a5-464e-46b23507f362@linux.ibm.com> Date: Thu, 19 May 2022 15:53:25 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH 2/2] target/s390x: kvm: Honor storage keys during emulation Content-Language: en-US To: Thomas Huth , qemu-s390x@nongnu.org, Christian Borntraeger , Halil Pasic Cc: "Michael S. Tsirkin" , Cornelia Huck , Paolo Bonzini , David Hildenbrand , qemu-devel@nongnu.org, Richard Henderson References: <20220506153956.2217601-1-scgl@linux.ibm.com> <20220506153956.2217601-3-scgl@linux.ibm.com> <21468730-e57f-a54a-bde4-6bb927d6b651@redhat.com> From: Janis Schoetterl-Glausch In-Reply-To: <21468730-e57f-a54a-bde4-6bb927d6b651@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: w43M2DY85xa053HGTy6E1PABTRj1Oh2X X-Proofpoint-ORIG-GUID: 68TDDuV0nj-oSeMZuhquhK1RIsgj38k5 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-05-19_03,2022-05-19_03,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 bulkscore=0 adultscore=0 suspectscore=0 phishscore=0 malwarescore=0 mlxscore=0 priorityscore=1501 clxscore=1015 mlxlogscore=999 spamscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2205190078 Received-SPF: pass client-ip=148.163.156.1; envelope-from=scgl@linux.ibm.com; helo=mx0a-001b2d01.pphosted.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 5/19/22 12:05, Thomas Huth wrote: > On 06/05/2022 17.39, Janis Schoetterl-Glausch wrote: >> Storage key controlled protection is currently not honored when >> emulating instructions. >> If available, enable key protection for the MEM_OP ioctl, thereby >> enabling it for the s390_cpu_virt_mem_* functions, when using kvm. >> As a result, the emulation of the following instructions honors storage >> keys: >> >> * CLP >>        The Synch I/O CLP command would need special handling in order >>        to support storage keys, but is currently not supported. >> * CHSC >>     Performing commands asynchronously would require special >>     handling, but commands are currently always synchronous. >> * STSI >> * TSCH >>     Must (and does) not change channel if terminated due to >>     protection. >> * MSCH >>     Suppressed on protection, works because fetching instruction. >> * SSCH >>     Suppressed on protection, works because fetching instruction. >> * STSCH >> * STCRW >>     Suppressed on protection, this works because no partial store is >>     possible, because the operand cannot span multiple pages. >> * PCISTB >> * MPCIFC >> * STPCIFC >> >> Signed-off-by: Janis Schoetterl-Glausch >> --- >>   target/s390x/kvm/kvm.c | 9 +++++++++ >>   1 file changed, 9 insertions(+) >> >> diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c >> index 53098bf541..7bd8db0e7b 100644 >> --- a/target/s390x/kvm/kvm.c >> +++ b/target/s390x/kvm/kvm.c >> @@ -151,12 +151,15 @@ const KVMCapabilityInfo kvm_arch_required_capabilities[] = { >>   static int cap_sync_regs; >>   static int cap_async_pf; >>   static int cap_mem_op; >> +static int cap_mem_op_extension; >>   static int cap_s390_irq; >>   static int cap_ri; >>   static int cap_hpage_1m; >>   static int cap_vcpu_resets; >>   static int cap_protected; >>   +static bool mem_op_storage_key_support; >> + >>   static int active_cmma; >>     static int kvm_s390_query_mem_limit(uint64_t *memory_limit) >> @@ -354,6 +357,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s) >>       cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS); >>       cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF); >>       cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP); >> +    cap_mem_op_extension = kvm_check_extension(s, KVM_CAP_S390_MEM_OP_EXTENSION); >> +    mem_op_storage_key_support = cap_mem_op_extension > 0; > > Ah, so KVM_CAP_S390_MEM_OP_EXTENSION is a "version number", not a boolean flag? ... ok, now I've finally understood that ... ;-) Yeah, potentially having a bunch of memop capabilities didn't seem nice to me. We can remove extensions if, when introducing an extension, we define that version x supports functionality y, z..., but for the storage keys I've written in api.rst that it's supported if the cap > 0. So we'd need a new cap if we want to get rid of the skey extension and still support some other extension, but that doesn't seem particularly likely. > > (would it be better to treat it as a flag field, so that certain extensions could go away again in the future? In that case, it would be better to check with "& 1" instead of "> 0" here) > >  Thomas >