From patchwork Fri Feb 14 22:26:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 11383341 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DA9AB191F for ; Fri, 14 Feb 2020 22:27:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B852B206D7 for ; Fri, 14 Feb 2020 22:27:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727849AbgBNW1Q (ORCPT ); Fri, 14 Feb 2020 17:27:16 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:23668 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727809AbgBNW1P (ORCPT ); Fri, 14 Feb 2020 17:27:15 -0500 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01EMNvtB134722; Fri, 14 Feb 2020 17:27:13 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2y5jxu9k4p-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:13 -0500 Received: from m0098414.ppops.net (m0098414.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01EMOcuv136018; Fri, 14 Feb 2020 17:27:12 -0500 Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0b-001b2d01.pphosted.com with ESMTP id 2y5jxu9k48-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:12 -0500 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01EMP8Rd008471; Fri, 14 Feb 2020 22:27:12 GMT Received: from b03cxnp08027.gho.boulder.ibm.com (b03cxnp08027.gho.boulder.ibm.com [9.17.130.19]) by ppma02dal.us.ibm.com with ESMTP id 2y5bc0vcy4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 22:27:11 +0000 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01EMR8fR60424610 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Feb 2020 22:27:08 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EECC3136098; Fri, 14 Feb 2020 22:27:07 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 16BCD136093; Fri, 14 Feb 2020 22:27:07 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 14 Feb 2020 22:27:06 +0000 (GMT) From: Christian Borntraeger To: Christian Borntraeger , Janosch Frank Cc: KVM , Cornelia Huck , David Hildenbrand , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , linux-s390 , Michael Mueller , Vasily Gorbik , Andrea Arcangeli , linux-mm@kvack.org, Janosch Frank Subject: [PATCH v2 06/42] s390/mm: add (non)secure page access exceptions handlers Date: Fri, 14 Feb 2020 17:26:22 -0500 Message-Id: <20200214222658.12946-7-borntraeger@de.ibm.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200214222658.12946-1-borntraeger@de.ibm.com> References: <20200214222658.12946-1-borntraeger@de.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-14_08:2020-02-14,2020-02-14 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 lowpriorityscore=0 malwarescore=0 impostorscore=0 mlxlogscore=999 bulkscore=0 adultscore=0 mlxscore=0 suspectscore=0 clxscore=1015 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002140165 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Vasily Gorbik Add exceptions handlers performing transparent transition of non-secure pages to secure (import) upon guest access and secure pages to non-secure (export) upon hypervisor access. Signed-off-by: Vasily Gorbik [frankja@linux.ibm.com: adding checks for failures] Signed-off-by: Janosch Frank [imbrenda@linux.ibm.com: adding a check for gmap fault] Signed-off-by: Claudio Imbrenda [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger --- arch/s390/kernel/pgm_check.S | 4 +- arch/s390/mm/fault.c | 78 ++++++++++++++++++++++++++++++++++++ 2 files changed, 80 insertions(+), 2 deletions(-) diff --git a/arch/s390/kernel/pgm_check.S b/arch/s390/kernel/pgm_check.S index eee3a482195a..2c27907a5ffc 100644 --- a/arch/s390/kernel/pgm_check.S +++ b/arch/s390/kernel/pgm_check.S @@ -78,8 +78,8 @@ PGM_CHECK(do_dat_exception) /* 39 */ PGM_CHECK(do_dat_exception) /* 3a */ PGM_CHECK(do_dat_exception) /* 3b */ PGM_CHECK_DEFAULT /* 3c */ -PGM_CHECK_DEFAULT /* 3d */ -PGM_CHECK_DEFAULT /* 3e */ +PGM_CHECK(do_secure_storage_access) /* 3d */ +PGM_CHECK(do_non_secure_storage_access) /* 3e */ PGM_CHECK_DEFAULT /* 3f */ PGM_CHECK(monitor_event_exception) /* 40 */ PGM_CHECK_DEFAULT /* 41 */ diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 7b0bb475c166..7bd86ebc882f 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -38,6 +38,7 @@ #include #include #include +#include #include "../kernel/entry.h" #define __FAIL_ADDR_MASK -4096L @@ -816,3 +817,80 @@ static int __init pfault_irq_init(void) early_initcall(pfault_irq_init); #endif /* CONFIG_PFAULT */ + +#if IS_ENABLED(CONFIG_PGSTE) +void do_secure_storage_access(struct pt_regs *regs) +{ + unsigned long addr = regs->int_parm_long & __FAIL_ADDR_MASK; + struct vm_area_struct *vma; + struct mm_struct *mm; + struct page *page; + int rc; + + switch (get_fault_type(regs)) { + case USER_FAULT: + mm = current->mm; + down_read(&mm->mmap_sem); + vma = find_vma(mm, addr); + if (!vma) { + up_read(&mm->mmap_sem); + do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP); + break; + } + page = follow_page(vma, addr, FOLL_WRITE | FOLL_GET); + if (IS_ERR_OR_NULL(page)) { + up_read(&mm->mmap_sem); + break; + } + if (arch_make_page_accessible(page)) + send_sig(SIGSEGV, current, 0); + put_page(page); + up_read(&mm->mmap_sem); + break; + case KERNEL_FAULT: + page = phys_to_page(addr); + if (unlikely(!try_get_page(page))) + break; + rc = arch_make_page_accessible(page); + put_page(page); + if (rc) + BUG(); + break; + case VDSO_FAULT: + /* fallthrough */ + case GMAP_FAULT: + /* fallthrough */ + default: + do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP); + WARN_ON_ONCE(1); + } +} +NOKPROBE_SYMBOL(do_secure_storage_access); + +void do_non_secure_storage_access(struct pt_regs *regs) +{ + unsigned long gaddr = regs->int_parm_long & __FAIL_ADDR_MASK; + struct gmap *gmap = (struct gmap *)S390_lowcore.gmap; + + if (get_fault_type(regs) != GMAP_FAULT) { + do_fault_error(regs, VM_READ | VM_WRITE, VM_FAULT_BADMAP); + WARN_ON_ONCE(1); + return; + } + + if (gmap_convert_to_secure(gmap, gaddr) == -EINVAL) + send_sig(SIGSEGV, current, 0); +} +NOKPROBE_SYMBOL(do_non_secure_storage_access); + +#else +void do_secure_storage_access(struct pt_regs *regs) +{ + default_trap_handler(regs); +} + +void do_non_secure_storage_access(struct pt_regs *regs) +{ + default_trap_handler(regs); +} +#endif