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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35ED6C7EE23 for ; Mon, 5 Jun 2023 09:03:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229670AbjFEJDa (ORCPT ); Mon, 5 Jun 2023 05:03:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44416 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229614AbjFEJD3 (ORCPT ); Mon, 5 Jun 2023 05:03:29 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C527199; Mon, 5 Jun 2023 02:03:27 -0700 (PDT) Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3558qbg5017256; Mon, 5 Jun 2023 09:03:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : date : mime-version : to : cc : references : from : subject : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=huYYXU8WTeOaiiUjj+/dTgKB1kjZU3fvDUrMeny2c0A=; b=OqoIuMqWYBiXC6xdkrPFYj8hW+iIbafNBCPJRiGHTcU1mwug+sdf3y23mxTYT44R7Dro Jc0EiznjnYwQGBzGlsqBZKYeA5V/3ce5QLoes0rzS8GodY8TtOAKFO1XYQG81lSbQW/i LQe62meMtA0voU40iqyX5pcJxXktDlox0G7z2/nwAIcTvrxK74LplobmwvUEP4XuHbP1 ZLv+TQbkqsKt55KdZqwk4HR7xpg4P0oeyQ+pSEyfHAFtOjsEvphk7PqcUiSD7zwQhBO2 J44vTCwIvMgsIm5/qomyxzMg8eYdxNuM4qX45y3LmWTTDagILx1LtZ3OAUFYKPv5bAQw dg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3r1cju08r3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 05 Jun 2023 09:03:26 +0000 Received: from m0360083.ppops.net (m0360083.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3558s1xN020980; Mon, 5 Jun 2023 09:03:26 GMT Received: from ppma04fra.de.ibm.com (6a.4a.5195.ip4.static.sl-reverse.com [149.81.74.106]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3r1cju08qc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 05 Jun 2023 09:03:26 +0000 Received: from pps.filterd (ppma04fra.de.ibm.com [127.0.0.1]) by ppma04fra.de.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3550sfFk016654; Mon, 5 Jun 2023 09:03:23 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma04fra.de.ibm.com (PPS) with ESMTPS id 3qyxbu901r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 05 Jun 2023 09:03:23 +0000 Received: from smtpav05.fra02v.mail.ibm.com (smtpav05.fra02v.mail.ibm.com [10.20.54.104]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 35593K2a24379962 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 5 Jun 2023 09:03:20 GMT Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 109B62004D; Mon, 5 Jun 2023 09:03:20 +0000 (GMT) Received: from smtpav05.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B935120043; Mon, 5 Jun 2023 09:03:19 +0000 (GMT) Received: from [9.171.39.161] (unknown [9.171.39.161]) by smtpav05.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 5 Jun 2023 09:03:19 +0000 (GMT) Message-ID: Date: Mon, 5 Jun 2023 11:03:19 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Content-Language: en-US To: Nico Boehr , imbrenda@linux.ibm.com, thuth@redhat.com Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org References: <20230601070202.152094-1-nrb@linux.ibm.com> <20230601070202.152094-4-nrb@linux.ibm.com> From: Janosch Frank Subject: Re: [kvm-unit-tests PATCH v3 3/6] s390x: sie: switch to home space mode before entering SIE In-Reply-To: <20230601070202.152094-4-nrb@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: il71Zz5fhjRKXlqkWXyUATh7lB81uL7X X-Proofpoint-ORIG-GUID: 0GRG7Wy3Dvhs04WW0xQGHyw-CdaX0SRR X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.176.26 definitions=2023-06-03_08,2023-06-02_02,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 adultscore=0 clxscore=1015 impostorscore=0 phishscore=0 spamscore=0 suspectscore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0 mlxscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2306050081 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On 6/1/23 09:01, Nico Boehr wrote: > This is to prepare for running guests without MSO/MSL, which is > currently not possible. This is a preparation patch for non-MSO/MSL guest support. > > We already have code in sie64a to setup a guest primary ASCE before > entering SIE, so we can in theory switch to the page tables which > translate gpa to hpa. The important information that's missing here is that SIE always uses the prim space for guest to host translations. > > But the host is running in primary space mode already, so changing the > primary ASCE before entering SIE will also affect the host's code and > data. And that's why this is an issue. For the time being we'll copy the primary ASCE into the home space ASCE. No functional change is intended. But if a test intends to.... > > To make this switch useful, the host should run in a different address > space mode. Hence, set up and change to home address space mode before > installing the guest ASCE. > > The home space ASCE is just copied over from the primary space ASCE, so > no functional change is intended, also for tests that want to use > MSO/MSL. If a test intends to use a different primary space ASCE, it can > now just set the guest.asce in the save_area. > > Signed-off-by: Nico Boehr > --- > lib/s390x/asm/arch_def.h | 1 + > lib/s390x/sie.c | 18 ++++++++++++++++++ > 2 files changed, 19 insertions(+) > > diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h > index 84f6996c4d8c..099289e7550e 100644 > --- a/lib/s390x/asm/arch_def.h > +++ b/lib/s390x/asm/arch_def.h > @@ -90,6 +90,7 @@ struct cpu { > #define AS_HOME 3 > > #define PSW_MASK_DAT 0x0400000000000000UL > +#define PSW_MASK_HOME 0x0000C00000000000UL > #define PSW_MASK_IO 0x0200000000000000UL > #define PSW_MASK_EXT 0x0100000000000000UL > #define PSW_MASK_KEY 0x00F0000000000000UL > diff --git a/lib/s390x/sie.c b/lib/s390x/sie.c > index 9241b4b4a512..ffa8ec91a423 100644 > --- a/lib/s390x/sie.c > +++ b/lib/s390x/sie.c > @@ -46,6 +46,8 @@ void sie_handle_validity(struct vm *vm) > > void sie(struct vm *vm) > { > + uint64_t old_cr13; > + > if (vm->sblk->sdf == 2) > memcpy(vm->sblk->pv_grregs, vm->save_area.guest.grs, > sizeof(vm->save_area.guest.grs)); > @@ -53,6 +55,16 @@ void sie(struct vm *vm) > /* Reset icptcode so we don't trip over it below */ > vm->sblk->icptcode = 0; > > + /* set up home address space to match primary space */ > + old_cr13 = stctg(13); > + lctlg(13, stctg(1)); > + > + /* switch to home space so guest tables can be different from host */ > + psw_mask_set_bits(PSW_MASK_HOME); > + > + /* also handle all interruptions in home space while in SIE */ > + irq_set_dat_mode(IRQ_DAT_ON, AS_HOME); I'm wondering why this needs to be two calls when you clearly want to have a convenience function that does a full space change. We could introduce: #define AS_REAL 4 static void mmu_set_addr_space(uint8_t space) { if (space < 4) psw_mask_set_bits(space); irq_set_dat_mode(space); } The "addr" in the function name is optional in my opinion. @Claudio: What's your opinion? > + > while (vm->sblk->icptcode == 0) { > sie64a(vm->sblk, &vm->save_area); > sie_handle_validity(vm); > @@ -60,6 +72,12 @@ void sie(struct vm *vm) > vm->save_area.guest.grs[14] = vm->sblk->gg14; > vm->save_area.guest.grs[15] = vm->sblk->gg15; > > + irq_set_dat_mode(IRQ_DAT_ON, AS_PRIM); > + psw_mask_clear_bits(PSW_MASK_HOME); > + > + /* restore the old CR 13 */ > + lctlg(13, old_cr13); > + > if (vm->sblk->sdf == 2) > memcpy(vm->save_area.guest.grs, vm->sblk->pv_grregs, > sizeof(vm->save_area.guest.grs));