From patchwork Fri Feb 4 15:53:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudio Imbrenda X-Patchwork-Id: 12735250 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 CA5FBC433F5 for ; Fri, 4 Feb 2022 15:54:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376423AbiBDPyM (ORCPT ); Fri, 4 Feb 2022 10:54:12 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:17936 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376275AbiBDPyD (ORCPT ); Fri, 4 Feb 2022 10:54:03 -0500 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 214FrDeS017304; Fri, 4 Feb 2022 15:54:03 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=2zLdKaE85V+2qiG6JE8eqhAObTmnsmKJ0bLt2qUlZn8=; b=KDR0I9w7wsLzt9+lLJw4KzARO1eYZ/5T5HOZrtWdstw7to6ZQCt7UqSUFnBYOL7rWhLd ZF7cdboUQ16j7uIgqR3XtaY+55Bgsu5KzbmN0QBFEDn74P1ZKJbv/GObfwWpdFnb4Vkc MQNtwD9YUFNI48AyzFS3790vuJf9JBYXKRinOGw6bj/SISjZnA59OuRGRfA3bqvW2HeS 0iNxejqew/dB/LUq4MiL7v33YSfrGM78zNl1sgtS9mAS9Y7YIOoW2AGk42+x4FzOf7Sr FSqxiUQkNUFb42bl69NwyDsVDdh/UMHrWAg9xuKqYkXHF4HpDIFJLs/xbY2jT8VoSoae Rg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3e0qx98ps8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Feb 2022 15:54:02 +0000 Received: from m0098417.ppops.net (m0098417.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 214FX1Fg012322; Fri, 4 Feb 2022 15:54:02 GMT Received: from ppma05fra.de.ibm.com (6c.4a.5195.ip4.static.sl-reverse.com [149.81.74.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 3e0qx98prh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Feb 2022 15:54:02 +0000 Received: from pps.filterd (ppma05fra.de.ibm.com [127.0.0.1]) by ppma05fra.de.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 214FlRan025629; Fri, 4 Feb 2022 15:54:00 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma05fra.de.ibm.com with ESMTP id 3e0r0x60hg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Feb 2022 15:54:00 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 214FrvtY32178522 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 4 Feb 2022 15:53:57 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 75F7EAE056; Fri, 4 Feb 2022 15:53:57 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E76C0AE045; Fri, 4 Feb 2022 15:53:56 +0000 (GMT) Received: from p-imbrenda.bredband2.com (unknown [9.145.8.50]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 4 Feb 2022 15:53:56 +0000 (GMT) From: Claudio Imbrenda To: kvm@vger.kernel.org Cc: borntraeger@de.ibm.com, frankja@linux.ibm.com, thuth@redhat.com, pasic@linux.ibm.com, david@redhat.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, scgl@linux.ibm.com Subject: [PATCH v7 11/17] s390/mm: KVM: pv: when tearing down, try to destroy protected pages Date: Fri, 4 Feb 2022 16:53:43 +0100 Message-Id: <20220204155349.63238-12-imbrenda@linux.ibm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220204155349.63238-1-imbrenda@linux.ibm.com> References: <20220204155349.63238-1-imbrenda@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: bNxDf81qEvBPTl4nxpvNTf95sEmgmOK7 X-Proofpoint-ORIG-GUID: xfvtg7qDo2rXX54jYKQV1Q4KPxfBbJdl X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-02-04_07,2022-02-03_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 suspectscore=0 lowpriorityscore=0 mlxscore=0 adultscore=0 phishscore=0 malwarescore=0 impostorscore=0 spamscore=0 priorityscore=1501 bulkscore=0 mlxlogscore=980 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2201110000 definitions=main-2202040088 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When ptep_get_and_clear_full is called for a mm teardown, we will now attempt to destroy the secure pages. This will be faster than export. In case it was not a teardown, or if for some reason the destroy page UVC failed, we try with an export page, like before. Signed-off-by: Claudio Imbrenda Acked-by: Janosch Frank --- arch/s390/include/asm/pgtable.h | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 23ca0d8e058a..72544a1b4a68 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1118,9 +1118,21 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, } else { res = ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); } - /* At this point the reference through the mapping is still present */ - if (mm_is_protected(mm) && pte_present(res)) - uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); + /* Nothing to do */ + if (!mm_is_protected(mm) || !pte_present(res)) + return res; + /* + * At this point the reference through the mapping is still present. + * The notifier should have destroyed all protected vCPUs at this + * point, so the destroy should be successful. + */ + if (full && !uv_destroy_owned_page(pte_val(res) & PAGE_MASK)) + return res; + /* + * But if something went wrong and the pages could not be destroyed, + * the slower export is used as fallback instead. + */ + uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK); return res; }