From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 657FB3BC68A; Wed, 1 Apr 2026 15:12:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775056360; cv=none; b=q50ourHPf0+TyTWz7Tr49UjoJWs/z/ImYF67M3DEjXCjoMsq299M2kVpuKw+Q6o+3ZtRyquWKJ5PVJoG7YYDZy7H3jDcv26PhAdCjJvrhHss+LSkaP8XvT+B1tPtSEcM1gWTVpPct9yJR4RwpJqKV3oUDniNjMdSiquR7oQv7P0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775056360; c=relaxed/simple; bh=evp5WHmP65YXB+ei9SNJyT07KxvYH91Z3UcOuQuAgyQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Gfa8+HEMTcWji2NgT3Uv7rYNSpoqM1o73YWa5ZNl63a8axlowWHEUPAbQyhB70/2Qq+UoGBrZVYSU/LifZrr7ot42r9opch8CIj13eEKumWl3Y1Rlkk73zK+QvOBVJOL9EoRaHU3sYw+ykVtUV//J0CVFgJKKFpSHQnxB2wlnDE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=oj15dyE3; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="oj15dyE3" Received: from pps.filterd (m0356517.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 6318ZLYb3518860; Wed, 1 Apr 2026 15:12:30 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=Y7j7t85hhaTdul5ic kmffTl5vlLPWKF/fkJO4lebKxw=; b=oj15dyE3XnzFJEoHOg0jog9rX2tpyrbFJ kRx6CRQd++Y3TK6OR9tFp0umXFF8wfHtR0SKtdYr/+2GH40sRQVL/dyJ6+n0pmdI BWFy+Cbdh9t4DjvbSXHUYngSUOVV64m4ZIDHl5GN7mbJGuff3B513j+e3WYs2zSi QI6uUpTcPOE/qP2nAhB6W0X/j0vm0Z+Tl2SWLHHTN72/gcVcbSp9sAcshUZn/r0Z r9Q5xEmX1cbr8ocfpbjvL9yH8IhPvENwaXNkoE3if5O8pJrzU7hHJ/F3vd1R8cEc zACr0vGdLvGcqJ5buYNNFXYpMzmbklyCYC2ETHKkGeu6SKrG/rI0g== Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4d66q38snq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 01 Apr 2026 15:12:29 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.2/8.18.1.2) with ESMTP id 631Ek4EA021631; Wed, 1 Apr 2026 15:12:28 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 4d6saspaex-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 01 Apr 2026 15:12:28 +0000 Received: from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com [10.20.54.102]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 631FCOeI59703640 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 1 Apr 2026 15:12:25 GMT Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CF6942004D; Wed, 1 Apr 2026 15:12:24 +0000 (GMT) Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A2F6320043; Wed, 1 Apr 2026 15:12:24 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.87.85.9]) by smtpav03.fra02v.mail.ibm.com (Postfix) with SMTP; Wed, 1 Apr 2026 15:12:24 +0000 (GMT) Received: by tuxmaker.boeblingen.de.ibm.com (Postfix, from userid 4958) id 8981AE0152; Wed, 01 Apr 2026 17:12:24 +0200 (CEST) From: Eric Farman To: Christian Borntraeger , Hendrik Brueckner , Janosch Frank , Claudio Imbrenda , David Hildenbrand Cc: Paolo Bonzini , Jonathan Corbet , Shuah Khan , kvm@vger.kernel.org, linux-s390@vger.kernel.org, Eric Farman Subject: [PATCH v2 1/4] KVM: s390: vsie: Allow non-zarch guests Date: Wed, 1 Apr 2026 17:12:18 +0200 Message-ID: <20260401151221.2272408-2-farman@linux.ibm.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260401151221.2272408-1-farman@linux.ibm.com> References: <20260401151221.2272408-1-farman@linux.ibm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-GUID: kXm7WxIYu7-LlyMdFrdNEWAcI-YREi7g X-Authority-Analysis: v=2.4 cv=frzRpV4f c=1 sm=1 tr=0 ts=69cd35dd cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=U7nrCbtTmkRpXpFmAIza:22 a=VnNF1IyMAAAA:8 a=TcF5ixnfVCNIaZDrkBwA:9 X-Proofpoint-ORIG-GUID: kXm7WxIYu7-LlyMdFrdNEWAcI-YREi7g X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDAxMDEzOCBTYWx0ZWRfX2fl6+RW5wBzE MfEAH4nlvI2xUrwqq7pSLp3ubSoquY5VhAwhiEGuetiRw+rGcvvd72x0wjJRvStDhlle2+nWhxs ZMesC9/zT9fACOQh+fgBzQzsW7LClHQKnYXGh3YYclcKMDc538W/XxlnZqjEZ69a/03xLxEKeU1 j5IjA9cYJ5GdHi3CkA07Tb1647SMD8B6k4AMwBhrdEURxJzO+v5nc/M6VJPfgfZspdt//FUO1EI a1Rrtc9RnjX7yq+m7hlps7Oty30u2ZQF0CW9YCq9+k5lQtvN4a+oXfASRlZwHa2Y0gt8D7sJB/C Sx2XIFCP5t7lqyRZxqdlrTgUnItOXNjyQo2Z7vHj49PDo2mAfnd1PyCSvNJ08Sa0dHBV1ZmiuW3 jZpeOVIOp1rIgjdgPWJViuvkCw247L8EUtjgGkQAhFwLNB9NcKn+3MJSYx6cNctJ2kHG6n9cfCv hWcueEHNbpx5QXQp8GQ== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-01_04,2026-04-01_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 spamscore=0 priorityscore=1501 malwarescore=0 clxscore=1015 lowpriorityscore=0 bulkscore=0 adultscore=0 suspectscore=0 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2604010138 Linux/KVM runs in z/Architecture-only mode. Although z/Architecture is built upon a long history of hardware refinements, any other CPU mode is not permitted. Allow a userspace to explicitly enable the use of ESA mode for nested guests, otherwise usage will be rejected. Reviewed-by: Janosch Frank Signed-off-by: Eric Farman --- arch/s390/include/asm/kvm_host.h | 1 + arch/s390/kvm/vsie.c | 8 +++++--- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm= _host.h index 3039c88daa63..8a4f4a39f7a2 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -656,6 +656,7 @@ struct kvm_arch { int user_stsi; int user_instr0; int user_operexec; + int allow_vsie_esamode; struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS]; wait_queue_head_t ipte_wq; int ipte_lock_count; diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 72895dddc39a..eee1b72e14df 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -125,8 +125,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, st= ruct vsie_page *vsie_page) struct kvm_s390_sie_block *scb_o =3D vsie_page->scb_o; int newflags, cpuflags =3D atomic_read(&scb_o->cpuflags); =20 - /* we don't allow ESA/390 guests */ - if (!(cpuflags & CPUSTAT_ZARCH)) + /* we don't allow ESA/390 guests unless explicitly enabled */ + if (!(cpuflags & CPUSTAT_ZARCH) && !vcpu->kvm->arch.allow_vsie_esamode) return set_validity_icpt(scb_s, 0x0001U); =20 if (cpuflags & (CPUSTAT_RRF | CPUSTAT_MCDS)) @@ -135,7 +135,9 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, st= ruct vsie_page *vsie_page) return set_validity_icpt(scb_s, 0x0007U); =20 /* intervention requests will be set later */ - newflags =3D CPUSTAT_ZARCH; + newflags =3D 0; + if (cpuflags & CPUSTAT_ZARCH) + newflags =3D CPUSTAT_ZARCH; if (cpuflags & CPUSTAT_GED && test_kvm_facility(vcpu->kvm, 8)) newflags |=3D CPUSTAT_GED; if (cpuflags & CPUSTAT_GED2 && test_kvm_facility(vcpu->kvm, 78)) { --=20 2.51.0