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 6FC1FC433F5 for ; Mon, 13 Dec 2021 21:06:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243079AbhLMVF7 (ORCPT ); Mon, 13 Dec 2021 16:05:59 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:40708 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243069AbhLMVF6 (ORCPT ); Mon, 13 Dec 2021 16:05:58 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 1BDKEXi2016722; Mon, 13 Dec 2021 21:05:58 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : content-transfer-encoding : mime-version; s=pp1; bh=t3TWAAhOaLt9lFmNABzDUZi10DdmbDvX90M4umnZp/0=; b=GpM5Q2arpD3N2ecbm7oI6s1GQC9nHSEBDFwN0MDpJeLDuQyJEjogBeFW1KDG4SeWyE4E 63Vurl3/2Fm/1OvfqA+Gz7PCfH0Tla0dXOrVT52muoW2T74myrpldgveJVSx4ZgdDYtG K2529psUdoPL1e9dvlKcGYXjIXvFHTbdFd7pwzactX4iTsds2WFkXI85DFXEfClue8ik Vu4tlmc69Ns+6JJMjZf2JqbWL9yFcgJcB2clQT1EOeLTZzBkYkyhoW+p/hlkvBheI6Af 7+h71dT5WslRCthHd99Y/rI7v2gEbTL9TW7NFO7gHSEv/pfUMmCcyi/gzHZ5C55hCkUA HQ== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3cx9r9eq3k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 13 Dec 2021 21:05:58 +0000 Received: from m0098404.ppops.net (m0098404.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 1BDL5w05021751; Mon, 13 Dec 2021 21:05:58 GMT Received: from ppma03ams.nl.ibm.com (62.31.33a9.ip4.static.sl-reverse.com [169.51.49.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 3cx9r9eq2u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 13 Dec 2021 21:05:57 +0000 Received: from pps.filterd (ppma03ams.nl.ibm.com [127.0.0.1]) by ppma03ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 1BDL2Spp007783; Mon, 13 Dec 2021 21:05:55 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma03ams.nl.ibm.com with ESMTP id 3cvkm98q0r-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 13 Dec 2021 21:05:55 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 1BDL5qcW46596528 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 13 Dec 2021 21:05:52 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E8893A404D; Mon, 13 Dec 2021 21:05:51 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DE124A4040; Mon, 13 Dec 2021 21:05:51 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Mon, 13 Dec 2021 21:05:51 +0000 (GMT) Received: by tuxmaker.boeblingen.de.ibm.com (Postfix, from userid 4958) id 7DA95E03A3; Mon, 13 Dec 2021 22:05:51 +0100 (CET) From: Eric Farman To: Christian Borntraeger , Janosch Frank , David Hildenbrand , Claudio Imbrenda , Thomas Huth Cc: Heiko Carstens , Vasily Gorbik , kvm@vger.kernel.org, linux-s390@vger.kernel.org, Eric Farman Subject: [RFC PATCH v5 0/1] s390x: Improvements to SIGP handling [KVM] Date: Mon, 13 Dec 2021 22:05:49 +0100 Message-Id: <20211213210550.856213-1-farman@linux.ibm.com> X-Mailer: git-send-email 2.32.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: U9x44KCpdeX-_MNSCqa-OyaefrwBkXlL X-Proofpoint-GUID: kbzfq52zXSaT7hZD3SOyXD3qS0d9VQx2 Content-Transfer-Encoding: 8bit X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-13_10,2021-12-13_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1015 priorityscore=1501 bulkscore=0 phishscore=0 mlxlogscore=762 mlxscore=0 adultscore=0 impostorscore=0 lowpriorityscore=0 spamscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2112130125 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Here is an update to the handling of SIGP between kernel and userspace. As before, I'm looking at problems encountered when a SIGP order that is processed in the kernel (for example, SIGP SENSE) is run concurrently with another one is processed in userspace (for example, SIGP STOP). Being able to provide an honest answer in the SIGP SENSE as to whether the targeted VCPU is/not stopped is important to provide a consistent answer while a guest OS is bringing its configuration online. This version was suggested by David Hildenbrand on v3 [1], where we examine the target vcpu for a pending STOP/RESTART IRQ while processing a SIGP order in-kernel, and returning the CC2 if one is in-flight. Unlike v2-v4 of this RFC, this solution requires no changes to userspace to exploit a new interface, but a small change is made on the QEMU side to keep the sequence of events in checks. Thoughts? [1] https://lore.kernel.org/r/858e4f2b-d601-a4f1-9e80-8f7838299c9a@redhat.com/ Previous RFCs: v1: https://lore.kernel.org/r/20211008203112.1979843-1-farman@linux.ibm.com/ v2: https://lore.kernel.org/r/20211102194652.2685098-1-farman@linux.ibm.com/ v3: https://lore.kernel.org/r/20211110203322.1374925-1-farman@linux.ibm.com/ v4: https://lore.kernel.org/r/20211119213707.2363945-1-farman@linux.ibm.com/ Eric Farman (1): KVM: s390: Clarify SIGP orders versus STOP/RESTART arch/s390/kvm/interrupt.c | 7 +++++++ arch/s390/kvm/kvm-s390.c | 9 +++++++-- arch/s390/kvm/kvm-s390.h | 1 + arch/s390/kvm/sigp.c | 28 ++++++++++++++++++++++++++++ 4 files changed, 43 insertions(+), 2 deletions(-) -- 2.32.0