From patchwork Fri Feb 14 22:26:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 11383333 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 E68C518B8 for ; Fri, 14 Feb 2020 22:27:13 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A1A41206D7 for ; Fri, 14 Feb 2020 22:27:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A1A41206D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=de.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 638716B06A9; Fri, 14 Feb 2020 17:27:11 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 5E8676B06AA; Fri, 14 Feb 2020 17:27:11 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4D65D6B06AB; Fri, 14 Feb 2020 17:27:11 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0252.hostedemail.com [216.40.44.252]) by kanga.kvack.org (Postfix) with ESMTP id 3663C6B06A9 for ; Fri, 14 Feb 2020 17:27:11 -0500 (EST) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D4F73181AEF21 for ; Fri, 14 Feb 2020 22:27:10 +0000 (UTC) X-FDA: 76490169420.16.teeth71_21805cf464959 X-Spam-Summary: 2,0,0,16ee5421ecc97042,d41d8cd98f00b204,borntraeger@de.ibm.com,:borntraeger@de.ibm.com:frankja@linux.vnet.ibm.com:akpm@linux-foundation.org:kvm@vger.kernel.org:cohuck@redhat.com:david@redhat.com:thuth@redhat.com:ulrich.weigand@de.ibm.com:imbrenda@linux.ibm.com:linux-s390@vger.kernel.org:mimu@linux.ibm.com:gor@linux.ibm.com:aarcange@redhat.com::will@kernel.org:sean.j.christopherson@intel.com,RULES_HIT:41:355:379:541:800:960:966:973:988:989:1260:1261:1311:1314:1345:1359:1437:1515:1535:1542:1711:1730:1747:1777:1792:2196:2198:2199:2200:2393:2559:2562:2693:2731:2897:2901:2918:3138:3139:3140:3141:3142:3354:3865:3866:3867:3868:3870:3871:3872:3874:4117:4250:4321:4385:4605:5007:6119:6261:6742:7576:7903:8634:8957:10004:11026:11473:11658:11914:12043:12296:12297:12438:12555:12663:12679:12895:12986:13223:13229:13894:14181:14394:14721:21080:21212:21324:21451:21627:21795:21990:30012:30051:30054,0,RBL:error,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SP X-HE-Tag: teeth71_21805cf464959 X-Filterd-Recvd-Size: 6925 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Fri, 14 Feb 2020 22:27:09 +0000 (UTC) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01EMOkaM004709; Fri, 14 Feb 2020 17:27:08 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y5x3hvf6s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:08 -0500 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01EMR77o009131; Fri, 14 Feb 2020 17:27:07 -0500 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y5x3hvf6e-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:07 -0500 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01EMP5k0007194; Fri, 14 Feb 2020 22:27:06 GMT Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by ppma03dal.us.ibm.com with ESMTP id 2y5bc0cdq6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 22:27:06 +0000 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01EMR31Z53871096 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Feb 2020 22:27:03 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 474F813609A; Fri, 14 Feb 2020 22:27:03 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4A54C136099; Fri, 14 Feb 2020 22:27:02 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 14 Feb 2020 22:27:02 +0000 (GMT) From: Christian Borntraeger To: Christian Borntraeger , Janosch Frank , Andrew Morton Cc: KVM , Cornelia Huck , David Hildenbrand , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , linux-s390 , Michael Mueller , Vasily Gorbik , Andrea Arcangeli , linux-mm@kvack.org, Will Deacon , Sean Christopherson Subject: [PATCH v2 01/42] mm:gup/writeback: add callbacks for inaccessible pages Date: Fri, 14 Feb 2020 17:26:17 -0500 Message-Id: <20200214222658.12946-2-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 phishscore=0 malwarescore=0 clxscore=1015 adultscore=0 mlxlogscore=928 priorityscore=1501 spamscore=0 bulkscore=0 mlxscore=0 impostorscore=0 suspectscore=2 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002140165 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Claudio Imbrenda With the introduction of protected KVM guests on s390 there is now a concept of inaccessible pages. These pages need to be made accessible before the host can access them. While cpu accesses will trigger a fault that can be resolved, I/O accesses will just fail. We need to add a callback into architecture code for places that will do I/O, namely when writeback is started or when a page reference is taken. This is not only to enable paging, file backing etc, it is also necessary to protect the host against a malicious user space. For example a bad QEMU could simply start direct I/O on such protected memory. We do not want userspace to be able to trigger I/O errors and thus we the logic is "whenever somebody accesses that page (gup) or doing I/O, make sure that this page can be accessed. When the guest tries to access that page we will wait in the page fault handler for writeback to have finished and for the page_ref to be the expected value. If wanted by others, the callbacks can be extended with error handlin and a parameter from where this is called. Signed-off-by: Claudio Imbrenda Signed-off-by: Christian Borntraeger --- include/linux/gfp.h | 6 ++++++ mm/gup.c | 2 ++ mm/page-writeback.c | 1 + 3 files changed, 9 insertions(+) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index e5b817cb86e7..be2754841369 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -485,6 +485,12 @@ static inline void arch_free_page(struct page *page, int order) { } #ifndef HAVE_ARCH_ALLOC_PAGE static inline void arch_alloc_page(struct page *page, int order) { } #endif +#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE +static inline int arch_make_page_accessible(struct page *page) +{ + return 0; +} +#endif struct page * __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, diff --git a/mm/gup.c b/mm/gup.c index 1b521e0ac1de..a1c15d029f7c 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -276,6 +276,7 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, page = ERR_PTR(-ENOMEM); goto out; } + arch_make_page_accessible(page); } if (flags & FOLL_TOUCH) { if ((flags & FOLL_WRITE) && @@ -1919,6 +1920,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, VM_BUG_ON_PAGE(compound_head(page) != head, page); + arch_make_page_accessible(page); SetPageReferenced(page); pages[*nr] = page; (*nr)++; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 2caf780a42e7..4c020e4ae71c 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2807,6 +2807,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write) inc_zone_page_state(page, NR_ZONE_WRITE_PENDING); } unlock_page_memcg(page); + arch_make_page_accessible(page); return ret; } From patchwork Fri Feb 14 22:26:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 11383339 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 A0E62186E for ; Fri, 14 Feb 2020 22:27:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5ABFC206D7 for ; Fri, 14 Feb 2020 22:27:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5ABFC206D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=de.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 527506B06AA; Fri, 14 Feb 2020 17:27:13 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 4DB0F6B06AB; Fri, 14 Feb 2020 17:27:13 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 379EF6B06AC; Fri, 14 Feb 2020 17:27:13 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0025.hostedemail.com [216.40.44.25]) by kanga.kvack.org (Postfix) with ESMTP id 1B3FD6B06AA for ; Fri, 14 Feb 2020 17:27:13 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B26554DCF for ; Fri, 14 Feb 2020 22:27:12 +0000 (UTC) X-FDA: 76490169504.18.brush17_21c786fbe1c5a X-Spam-Summary: 2,0,0,339df718e75f115d,d41d8cd98f00b204,borntraeger@de.ibm.com,:borntraeger@de.ibm.com:frankja@linux.vnet.ibm.com:kvm@vger.kernel.org:cohuck@redhat.com:david@redhat.com:thuth@redhat.com:ulrich.weigand@de.ibm.com:imbrenda@linux.ibm.com:linux-s390@vger.kernel.org:mimu@linux.ibm.com:gor@linux.ibm.com:aarcange@redhat.com:,RULES_HIT:4:41:355:379:541:800:960:966:968:973:988:989:1260:1261:1311:1314:1345:1359:1431:1437:1515:1605:1730:1747:1777:1792:1801:1981:2194:2196:2199:2200:2393:2559:2562:2693:3138:3139:3140:3141:3142:3165:3865:3866:3867:3868:3870:3871:3872:3874:4250:4321:4385:4605:5007:6119:6120:6261:6742:7576:7875:7901:7903:8568:8634:8957:9010:9040:10004:11026:11473:11657:11658:11914:12043:12291:12296:12297:12438:12555:12663:12679:12895:12986:13255:13894:14096:14394:21080:21324:21433:21451:21611:21627:21789:21990:30003:30045:30054:30070:30091,0,RBL:error,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom _rules:0 X-HE-Tag: brush17_21c786fbe1c5a X-Filterd-Recvd-Size: 18950 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Fri, 14 Feb 2020 22:27:11 +0000 (UTC) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01EMNnkP088749; Fri, 14 Feb 2020 17:27:11 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2y5vhq05uc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:11 -0500 Received: from m0098420.ppops.net (m0098420.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01EMOul5090479; Fri, 14 Feb 2020 17:27:10 -0500 Received: from ppma02wdc.us.ibm.com (aa.5b.37a9.ip4.static.sl-reverse.com [169.55.91.170]) by mx0b-001b2d01.pphosted.com with ESMTP id 2y5vhq05tu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:10 -0500 Received: from pps.filterd (ppma02wdc.us.ibm.com [127.0.0.1]) by ppma02wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01EMR5YT013658; Fri, 14 Feb 2020 22:27:10 GMT Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by ppma02wdc.us.ibm.com with ESMTP id 2y5bc09wqe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 22:27:10 +0000 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01EMR7FZ44433752 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Feb 2020 22:27:07 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E4FB6136091; Fri, 14 Feb 2020 22:27:06 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 08E19136094; Fri, 14 Feb 2020 22:27:06 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 14 Feb 2020 22:27:05 +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 Subject: [PATCH v2 05/42] s390/mm: provide memory management functions for protected KVM guests Date: Fri, 14 Feb 2020 17:26:21 -0500 Message-Id: <20200214222658.12946-6-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 lowpriorityscore=0 bulkscore=0 mlxlogscore=995 suspectscore=2 phishscore=0 impostorscore=0 priorityscore=1501 malwarescore=0 spamscore=0 clxscore=1015 adultscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002140165 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Claudio Imbrenda This provides the basic ultravisor calls and page table handling to cope with secure guests: - provide arch_make_page_accessible - make pages accessible after unmapping of secure guests - provide the ultravisor commands convert to/from secure - provide the ultravisor commands pin/unpin shared - provide callbacks to make pages secure (inacccessible) - we check for the expected pin count to only make pages secure if the host is not accessing them - we fence hugetlbfs for secure pages Co-developed-by: Ulrich Weigand Signed-off-by: Ulrich Weigand Signed-off-by: Claudio Imbrenda [borntraeger@de.ibm.com: patch merging, splitting, fixing] Signed-off-by: Christian Borntraeger --- arch/s390/include/asm/gmap.h | 4 + arch/s390/include/asm/mmu.h | 2 + arch/s390/include/asm/mmu_context.h | 1 + arch/s390/include/asm/page.h | 5 + arch/s390/include/asm/pgtable.h | 35 ++++- arch/s390/include/asm/uv.h | 31 ++++ arch/s390/kernel/uv.c | 223 ++++++++++++++++++++++++++++ 7 files changed, 296 insertions(+), 5 deletions(-) diff --git a/arch/s390/include/asm/gmap.h b/arch/s390/include/asm/gmap.h index 37f96b6f0e61..3c4926aa78f4 100644 --- a/arch/s390/include/asm/gmap.h +++ b/arch/s390/include/asm/gmap.h @@ -9,6 +9,7 @@ #ifndef _ASM_S390_GMAP_H #define _ASM_S390_GMAP_H +#include #include /* Generic bits for GMAP notification on DAT table entry changes. */ @@ -31,6 +32,7 @@ * @table: pointer to the page directory * @asce: address space control element for gmap page table * @pfault_enabled: defines if pfaults are applicable for the guest + * @guest_handle: protected virtual machine handle for the ultravisor * @host_to_rmap: radix tree with gmap_rmap lists * @children: list of shadow gmap structures * @pt_list: list of all page tables used in the shadow guest address space @@ -54,6 +56,8 @@ struct gmap { unsigned long asce_end; void *private; bool pfault_enabled; + /* only set for protected virtual machines */ + unsigned long guest_handle; /* Additional data for shadow guest address spaces */ struct radix_tree_root host_to_rmap; struct list_head children; diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h index bcfb6371086f..e21b618ad432 100644 --- a/arch/s390/include/asm/mmu.h +++ b/arch/s390/include/asm/mmu.h @@ -16,6 +16,8 @@ typedef struct { unsigned long asce; unsigned long asce_limit; unsigned long vdso_base; + /* The mmu context belongs to a secure guest. */ + atomic_t is_protected; /* * The following bitfields need a down_write on the mm * semaphore when they are written to. As they are only diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index 8d04e6f3f796..afa836014076 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -23,6 +23,7 @@ static inline int init_new_context(struct task_struct *tsk, INIT_LIST_HEAD(&mm->context.gmap_list); cpumask_clear(&mm->context.cpu_attach_mask); atomic_set(&mm->context.flush_count, 0); + atomic_set(&mm->context.is_protected, 0); mm->context.gmap_asce = 0; mm->context.flush_mm = 0; mm->context.compat_mm = test_thread_flag(TIF_31BIT); diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h index 85e944f04c70..4ebcf891ff3c 100644 --- a/arch/s390/include/asm/page.h +++ b/arch/s390/include/asm/page.h @@ -153,6 +153,11 @@ static inline int devmem_is_allowed(unsigned long pfn) #define HAVE_ARCH_FREE_PAGE #define HAVE_ARCH_ALLOC_PAGE +#if IS_ENABLED(CONFIG_PGSTE) +int arch_make_page_accessible(struct page *page); +#define HAVE_ARCH_MAKE_PAGE_ACCESSIBLE +#endif + #endif /* !__ASSEMBLY__ */ #define __PAGE_OFFSET 0x0UL diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 137a3920ca36..cc7a1adacb94 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -19,6 +19,7 @@ #include #include #include +#include extern pgd_t swapper_pg_dir[]; extern void paging_init(void); @@ -520,6 +521,15 @@ static inline int mm_has_pgste(struct mm_struct *mm) return 0; } +static inline int mm_is_protected(struct mm_struct *mm) +{ +#ifdef CONFIG_PGSTE + if (unlikely(atomic_read(&mm->context.is_protected))) + return 1; +#endif + return 0; +} + static inline int mm_alloc_pgste(struct mm_struct *mm) { #ifdef CONFIG_PGSTE @@ -1061,7 +1071,12 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); + pte_t res; + + res = ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); + if (mm_is_protected(mm) && pte_present(res)) + uv_convert_from_secure(pte_val(res) & PAGE_MASK); + return res; } #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION @@ -1073,7 +1088,12 @@ void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long, static inline pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { - return ptep_xchg_direct(vma->vm_mm, addr, ptep, __pte(_PAGE_INVALID)); + pte_t res; + + res = ptep_xchg_direct(vma->vm_mm, addr, ptep, __pte(_PAGE_INVALID)); + if (mm_is_protected(vma->vm_mm) && pte_present(res)) + uv_convert_from_secure(pte_val(res) & PAGE_MASK); + return res; } /* @@ -1088,12 +1108,17 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, unsigned long addr, pte_t *ptep, int full) { + pte_t res; + if (full) { - pte_t pte = *ptep; + res = *ptep; *ptep = __pte(_PAGE_INVALID); - return pte; + } else { + res = ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); } - return ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID)); + if (mm_is_protected(mm) && pte_present(res)) + uv_convert_from_secure(pte_val(res) & PAGE_MASK); + return res; } #define __HAVE_ARCH_PTEP_SET_WRPROTECT diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h index f5b55e3972b3..e45963cc7f40 100644 --- a/arch/s390/include/asm/uv.h +++ b/arch/s390/include/asm/uv.h @@ -15,6 +15,7 @@ #include #include #include +#include #define UVC_RC_EXECUTED 0x0001 #define UVC_RC_INV_CMD 0x0002 @@ -24,6 +25,10 @@ #define UVC_CMD_QUI 0x0001 #define UVC_CMD_INIT_UV 0x000f +#define UVC_CMD_CONV_TO_SEC_STOR 0x0200 +#define UVC_CMD_CONV_FROM_SEC_STOR 0x0201 +#define UVC_CMD_PIN_PAGE_SHARED 0x0341 +#define UVC_CMD_UNPIN_PAGE_SHARED 0x0342 #define UVC_CMD_SET_SHARED_ACCESS 0x1000 #define UVC_CMD_REMOVE_SHARED_ACCESS 0x1001 @@ -31,8 +36,12 @@ enum uv_cmds_inst { BIT_UVC_CMD_QUI = 0, BIT_UVC_CMD_INIT_UV = 1, + BIT_UVC_CMD_CONV_TO_SEC_STOR = 6, + BIT_UVC_CMD_CONV_FROM_SEC_STOR = 7, BIT_UVC_CMD_SET_SHARED_ACCESS = 8, BIT_UVC_CMD_REMOVE_SHARED_ACCESS = 9, + BIT_UVC_CMD_PIN_PAGE_SHARED = 21, + BIT_UVC_CMD_UNPIN_PAGE_SHARED = 22, }; struct uv_cb_header { @@ -69,6 +78,19 @@ struct uv_cb_init { u64 reserved28[4]; } __packed __aligned(8); +struct uv_cb_cts { + struct uv_cb_header header; + u64 reserved08[2]; + u64 guest_handle; + u64 gaddr; +} __packed __aligned(8); + +struct uv_cb_cfs { + struct uv_cb_header header; + u64 reserved08[2]; + u64 paddr; +} __packed __aligned(8); + struct uv_cb_share { struct uv_cb_header header; u64 reserved08[3]; @@ -170,12 +192,21 @@ static inline int is_prot_virt_host(void) return prot_virt_host; } +int gmap_make_secure(struct gmap *gmap, unsigned long gaddr, void *uvcb); +int uv_convert_from_secure(unsigned long paddr); +int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr); + void setup_uv(void); void adjust_to_uv_max(unsigned long *vmax); #else #define is_prot_virt_host() 0 static inline void setup_uv(void) {} static inline void adjust_to_uv_max(unsigned long *vmax) {} + +static inline int uv_convert_from_secure(unsigned long paddr) +{ + return 0; +} #endif #if defined(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) || \ diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c index 1424994f5489..9a6c309864a0 100644 --- a/arch/s390/kernel/uv.c +++ b/arch/s390/kernel/uv.c @@ -12,6 +12,8 @@ #include #include #include +#include +#include #include #include #include @@ -100,4 +102,225 @@ void adjust_to_uv_max(unsigned long *vmax) { *vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr); } + +/* + * Requests the Ultravisor to pin the page in the shared state. This will + * cause an intercept when the guest attempts to unshare the pinned page. + */ +static int uv_pin_shared(unsigned long paddr) +{ + struct uv_cb_cfs uvcb = { + .header.cmd = UVC_CMD_PIN_PAGE_SHARED, + .header.len = sizeof(uvcb), + .paddr = paddr, + }; + + if (uv_call(0, (u64)&uvcb)) + return -EINVAL; + return 0; +} + +/* + * Requests the Ultravisor to encrypt a guest page and make it + * accessible to the host for paging (export). + * + * @paddr: Absolute host address of page to be exported + */ +int uv_convert_from_secure(unsigned long paddr) +{ + struct uv_cb_cfs uvcb = { + .header.cmd = UVC_CMD_CONV_FROM_SEC_STOR, + .header.len = sizeof(uvcb), + .paddr = paddr + }; + + if (uv_call(0, (u64)&uvcb)) + return -EINVAL; + return 0; +} + +/* + * Calculate the expected ref_count for a page that would otherwise have no + * further pins. This was cribbed from similar functions in other places in + * the kernel, but with some slight modifications. We know that a secure + * page can not be a huge page for example. + */ +static int expected_page_refs(struct page *page) +{ + int res; + + res = page_mapcount(page); + if (PageSwapCache(page)) { + res++; + } else if (page_mapping(page)) { + res++; + if (page_has_private(page)) + res++; + } + return res; +} + +static int make_secure_pte(pte_t *ptep, unsigned long addr, + struct page *exp_page, struct uv_cb_header *uvcb) +{ + pte_t entry = READ_ONCE(*ptep); + struct page *page; + int expected, rc = 0; + + if (!pte_present(entry)) + return -ENXIO; + if (pte_val(entry) & _PAGE_INVALID) + return -ENXIO; + + page = pte_page(entry); + if (page != exp_page) + return -ENXIO; + if (PageWriteback(page)) + return -EAGAIN; + expected = expected_page_refs(page); + if (!page_ref_freeze(page, expected)) + return -EBUSY; + set_bit(PG_arch_1, &page->flags); + rc = uv_call(0, (u64)uvcb); + page_ref_unfreeze(page, expected); + /* Return -ENXIO if the page was not mapped, -EINVAL otherwise */ + if (rc) + rc = uvcb->rc == 0x10a ? -ENXIO : -EINVAL; + return rc; +} + +/* + * Requests the Ultravisor to make a page accessible to a guest. + * If it's brought in the first time, it will be cleared. If + * it has been exported before, it will be decrypted and integrity + * checked. + */ +int gmap_make_secure(struct gmap *gmap, unsigned long gaddr, void *uvcb) +{ + struct vm_area_struct *vma; + unsigned long uaddr; + struct page *page; + int rc, local_drain = 0; + spinlock_t *ptelock; + pte_t *ptep; + +again: + rc = -EFAULT; + down_read(&gmap->mm->mmap_sem); + + uaddr = __gmap_translate(gmap, gaddr); + if (IS_ERR_VALUE(uaddr)) + goto out; + vma = find_vma(gmap->mm, uaddr); + if (!vma) + goto out; + /* + * Secure pages cannot be huge and userspace should not combine both. + * In case userspace does it anyway this will result in an -EFAULT for + * the unpack. The guest is thus never reaching secure mode. If + * userspace is playing dirty tricky with mapping huge pages later + * on this will result in a segmenation fault. + */ + if (is_vm_hugetlb_page(vma)) + goto out; + + rc = -ENXIO; + page = follow_page(vma, uaddr, FOLL_WRITE); + if (IS_ERR_OR_NULL(page)) + goto out; + + lock_page(page); + ptep = get_locked_pte(gmap->mm, uaddr, &ptelock); + rc = make_secure_pte(ptep, uaddr, page, uvcb); + pte_unmap_unlock(ptep, ptelock); + unlock_page(page); +out: + up_read(&gmap->mm->mmap_sem); + + if (rc == -EAGAIN) { + wait_on_page_writeback(page); + } else if (rc == -EBUSY) { + /* + * If we have tried a local drain and the page refcount + * still does not match our expected safe value, try with a + * system wide drain. This is needed if the pagevecs holding + * the page are on a different CPU. + */ + if (local_drain) { + lru_add_drain_all(); + /* We give up here, and let the caller try again */ + return -EAGAIN; + } + /* + * We are here if the page refcount does not match the + * expected safe value. The main culprits are usually + * pagevecs. With lru_add_drain() we drain the pagevecs + * on the local CPU so that hopefully the refcount will + * reach the expected safe value. + */ + lru_add_drain(); + local_drain = 1; + /* And now we try again immediately after draining */ + goto again; + } else if (rc == -ENXIO) { + if (gmap_fault(gmap, gaddr, FAULT_FLAG_WRITE)) + return -EFAULT; + return -EAGAIN; + } + return rc; +} +EXPORT_SYMBOL_GPL(gmap_make_secure); + +int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr) +{ + struct uv_cb_cts uvcb = { + .header.cmd = UVC_CMD_CONV_TO_SEC_STOR, + .header.len = sizeof(uvcb), + .guest_handle = gmap->guest_handle, + .gaddr = gaddr, + }; + + return gmap_make_secure(gmap, gaddr, &uvcb); +} +EXPORT_SYMBOL_GPL(gmap_convert_to_secure); + +/** + * To be called with the page locked or with an extra reference! + */ +int arch_make_page_accessible(struct page *page) +{ + int rc = 0; + + /* Hugepage cannot be protected, so nothing to do */ + if (PageHuge(page)) + return 0; + + /* + * PG_arch_1 is used in 3 places: + * 1. for kernel page tables during early boot + * 2. for storage keys of huge pages and KVM + * 3. As an indication that this page might be secure. This can + * overindicate, e.g. we set the bit before calling + * convert_to_secure. + * As secure pages are never huge, all 3 variants can co-exists. + */ + if (!test_bit(PG_arch_1, &page->flags)) + return 0; + + rc = uv_pin_shared(page_to_phys(page)); + if (!rc) { + clear_bit(PG_arch_1, &page->flags); + return 0; + } + + rc = uv_convert_from_secure(page_to_phys(page)); + if (!rc) { + clear_bit(PG_arch_1, &page->flags); + return 0; + } + + return rc; +} +EXPORT_SYMBOL_GPL(arch_make_page_accessible); + #endif 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: 11383345 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 A4AB11820 for ; Fri, 14 Feb 2020 22:27:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 72417206D7 for ; Fri, 14 Feb 2020 22:27:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 72417206D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=de.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CEF416B06AB; Fri, 14 Feb 2020 17:27:14 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id C7CFB6B06AC; Fri, 14 Feb 2020 17:27:14 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B19586B06AD; Fri, 14 Feb 2020 17:27:14 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0228.hostedemail.com [216.40.44.228]) by kanga.kvack.org (Postfix) with ESMTP id 9761A6B06AB for ; Fri, 14 Feb 2020 17:27:14 -0500 (EST) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2FFAC180AD81F for ; Fri, 14 Feb 2020 22:27:14 +0000 (UTC) X-FDA: 76490169588.03.trail23_2208a51de9e3f X-Spam-Summary: 2,0,0,bd5c7ecf0d27dc51,d41d8cd98f00b204,borntraeger@de.ibm.com,:borntraeger@de.ibm.com:frankja@linux.vnet.ibm.com:kvm@vger.kernel.org:cohuck@redhat.com:david@redhat.com:thuth@redhat.com:ulrich.weigand@de.ibm.com:imbrenda@linux.ibm.com:linux-s390@vger.kernel.org:mimu@linux.ibm.com:gor@linux.ibm.com:aarcange@redhat.com::frankja@linux.ibm.com,RULES_HIT:41:355:379:541:800:960:973:988:989:1260:1261:1311:1314:1345:1359:1431:1437:1515:1535:1543:1711:1730:1747:1777:1792:2393:2559:2562:2901:3138:3139:3140:3141:3142:3354:3866:3867:3868:4118:4605:5007:6261:6742:7576:8568:8634:10004:11026:11473:11657:11658:11914:12043:12291:12296:12297:12438:12555:12663:12679:12683:12895:13894:14096:14181:14394:14721:21080:21324:21433:21451:21627:21990:30054:30070,0,RBL:error,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: trail23_2208a51de9e3f X-Filterd-Recvd-Size: 7647 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Fri, 14 Feb 2020 22:27:13 +0000 (UTC) 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 From patchwork Fri Feb 14 22:26:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 11383383 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 C90FD17F0 for ; Fri, 14 Feb 2020 22:27:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8A3442082F for ; Fri, 14 Feb 2020 22:27:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8A3442082F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=de.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CEE966B06AE; Fri, 14 Feb 2020 17:27:45 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id C9E906B06AF; Fri, 14 Feb 2020 17:27:45 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BDBCC6B06B0; Fri, 14 Feb 2020 17:27:45 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0079.hostedemail.com [216.40.44.79]) by kanga.kvack.org (Postfix) with ESMTP id A5CD06B06AE for ; Fri, 14 Feb 2020 17:27:45 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 41B334DC4 for ; Fri, 14 Feb 2020 22:27:45 +0000 (UTC) X-FDA: 76490170890.09.oil69_268575ac21737 X-Spam-Summary: 2,0,0,6a0f2ef9d5d479d5,d41d8cd98f00b204,borntraeger@de.ibm.com,:borntraeger@de.ibm.com:frankja@linux.vnet.ibm.com:akpm@linux-foundation.org:kvm@vger.kernel.org:cohuck@redhat.com:david@redhat.com:thuth@redhat.com:ulrich.weigand@de.ibm.com:imbrenda@linux.ibm.com:linux-s390@vger.kernel.org:mimu@linux.ibm.com:gor@linux.ibm.com:aarcange@redhat.com::will@kernel.org:sean.j.christopherson@intel.com,RULES_HIT:41:355:379:541:800:960:973:988:989:1260:1261:1311:1314:1345:1359:1437:1515:1535:1542:1711:1730:1747:1777:1792:2393:2559:2562:3138:3139:3140:3141:3142:3353:3865:3867:3868:3871:3872:3874:4117:4321:4605:5007:6261:6742:7576:8634:8957:9592:10004:11026:11473:11658:11914:12043:12296:12297:12438:12555:12663:12679:12895:12986:13153:13228:13255:13894:14181:14394:14721:21080:21212:21451:21627:21990:30003:30054,0,RBL:148.163.158.5:@de.ibm.com:.lbl8.mailshell.net-62.2.0.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0, DNSBL:ne X-HE-Tag: oil69_268575ac21737 X-Filterd-Recvd-Size: 6531 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Fri, 14 Feb 2020 22:27:44 +0000 (UTC) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01EMOQwt140482; Fri, 14 Feb 2020 17:27:42 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y4j897ny6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:41 -0500 Received: from m0098417.ppops.net (m0098417.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01EMQPA0144752; Fri, 14 Feb 2020 17:27:41 -0500 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y4j897nxj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:41 -0500 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01EMRBsq019920; Fri, 14 Feb 2020 22:27:40 GMT Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by ppma04dal.us.ibm.com with ESMTP id 2y5bc0cd9x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 22:27:40 +0000 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01EMRb6B57540952 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Feb 2020 22:27:37 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 47335136093; Fri, 14 Feb 2020 22:27:37 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4A879136091; Fri, 14 Feb 2020 22:27:36 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 14 Feb 2020 22:27:36 +0000 (GMT) From: Christian Borntraeger To: Christian Borntraeger , Janosch Frank , Andrew Morton Cc: KVM , Cornelia Huck , David Hildenbrand , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , linux-s390 , Michael Mueller , Vasily Gorbik , Andrea Arcangeli , linux-mm@kvack.org, Will Deacon , Sean Christopherson Subject: [PATCH v2 39/42] example for future extension: mm:gup/writeback: add callbacks for inaccessible pages: error cases Date: Fri, 14 Feb 2020 17:26:55 -0500 Message-Id: <20200214222658.12946-40-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 mlxlogscore=942 impostorscore=0 priorityscore=1501 spamscore=0 adultscore=0 mlxscore=0 malwarescore=0 phishscore=0 clxscore=1015 lowpriorityscore=0 suspectscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002140165 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Claudio Imbrenda This is a potential extension to do error handling if we fail to make the page accessible if we know what others need. Signed-off-by: Claudio Imbrenda Acked-by: Will Deacon --- mm/gup.c | 17 ++++++++++++----- mm/page-writeback.c | 6 +++++- 2 files changed, 17 insertions(+), 6 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index a1c15d029f7c..354bcfbd844b 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -193,6 +193,7 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, struct page *page; spinlock_t *ptl; pte_t *ptep, pte; + int ret; /* FOLL_GET and FOLL_PIN are mutually exclusive. */ if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == @@ -250,8 +251,6 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, if (is_zero_pfn(pte_pfn(pte))) { page = pte_page(pte); } else { - int ret; - ret = follow_pfn_pte(vma, address, ptep, flags); page = ERR_PTR(ret); goto out; @@ -259,7 +258,6 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, } if (flags & FOLL_SPLIT && PageTransCompound(page)) { - int ret; get_page(page); pte_unmap_unlock(ptep, ptl); lock_page(page); @@ -276,7 +274,12 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, page = ERR_PTR(-ENOMEM); goto out; } - arch_make_page_accessible(page); + ret = arch_make_page_accessible(page); + if (ret) { + put_page(page); + page = ERR_PTR(ret); + goto out; + } } if (flags & FOLL_TOUCH) { if ((flags & FOLL_WRITE) && @@ -1920,7 +1923,11 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, VM_BUG_ON_PAGE(compound_head(page) != head, page); - arch_make_page_accessible(page); + ret = arch_make_page_accessible(page); + if (ret) { + put_page(head); + goto pte_unmap; + } SetPageReferenced(page); pages[*nr] = page; (*nr)++; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 4c020e4ae71c..558d7063c117 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2807,7 +2807,11 @@ int __test_set_page_writeback(struct page *page, bool keep_write) inc_zone_page_state(page, NR_ZONE_WRITE_PENDING); } unlock_page_memcg(page); - arch_make_page_accessible(page); + /* + * If writeback has been triggered on a page that cannot be made + * accessible, it is too late. + */ + WARN_ON(arch_make_page_accessible(page)); return ret; } From patchwork Fri Feb 14 22:26:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 11383389 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 7A11D1820 for ; Fri, 14 Feb 2020 22:27:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 433462082F for ; Fri, 14 Feb 2020 22:27:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 433462082F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=de.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A31426B06B0; Fri, 14 Feb 2020 17:27:46 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 9E0CF6B06B1; Fri, 14 Feb 2020 17:27:46 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8D0126B06B2; Fri, 14 Feb 2020 17:27:46 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0204.hostedemail.com [216.40.44.204]) by kanga.kvack.org (Postfix) with ESMTP id 6DC926B06B0 for ; Fri, 14 Feb 2020 17:27:46 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 154CE181AEF21 for ; Fri, 14 Feb 2020 22:27:46 +0000 (UTC) X-FDA: 76490170932.26.knife34_26a8e2c331227 X-Spam-Summary: 2,0,0,444c68c39f3f164f,d41d8cd98f00b204,borntraeger@de.ibm.com,:borntraeger@de.ibm.com:frankja@linux.vnet.ibm.com:akpm@linux-foundation.org:kvm@vger.kernel.org:cohuck@redhat.com:david@redhat.com:thuth@redhat.com:ulrich.weigand@de.ibm.com:imbrenda@linux.ibm.com:linux-s390@vger.kernel.org:mimu@linux.ibm.com:gor@linux.ibm.com:aarcange@redhat.com::will@kernel.org:sean.j.christopherson@intel.com,RULES_HIT:41:355:379:541:800:960:966:973:982:988:989:1260:1261:1311:1314:1345:1359:1437:1515:1535:1542:1711:1730:1747:1777:1792:1981:2194:2196:2198:2199:2200:2201:2393:2559:2562:2693:2731:3138:3139:3140:3141:3142:3353:3867:3871:3872:3874:4117:4321:4385:4605:5007:6261:6742:7576:8634:10004:11026:11232:11473:11658:11914:12043:12296:12297:12438:12555:12663:12679:12895:12986:13255:13894:14096:14181:14394:14721:21080:21212:21451:21627:21990:30054:30064,0,RBL:148.163.156.1:@de.ibm.com:.lbl8.mailshell.net-62.2.0.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,Dom ainCache X-HE-Tag: knife34_26a8e2c331227 X-Filterd-Recvd-Size: 6461 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf44.hostedemail.com (Postfix) with ESMTP for ; Fri, 14 Feb 2020 22:27:45 +0000 (UTC) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01EMP19d004936; Fri, 14 Feb 2020 17:27:44 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y5g8cchmd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:43 -0500 Received: from m0098404.ppops.net (m0098404.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 01EMPNm4006033; Fri, 14 Feb 2020 17:27:43 -0500 Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0a-001b2d01.pphosted.com with ESMTP id 2y5g8cchk8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 17:27:42 -0500 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 01EMP6Ha015199; Fri, 14 Feb 2020 22:27:41 GMT Received: from b03cxnp08027.gho.boulder.ibm.com (b03cxnp08027.gho.boulder.ibm.com [9.17.130.19]) by ppma01wdc.us.ibm.com with ESMTP id 2y5bc01xjb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 Feb 2020 22:27:41 +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 01EMRcFL58982806 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 14 Feb 2020 22:27:38 GMT Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5E0E1136096; Fri, 14 Feb 2020 22:27:38 +0000 (GMT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 62341136091; Fri, 14 Feb 2020 22:27:37 +0000 (GMT) Received: from localhost.localdomain (unknown [9.114.17.106]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 14 Feb 2020 22:27:37 +0000 (GMT) From: Christian Borntraeger To: Christian Borntraeger , Janosch Frank , Andrew Morton Cc: KVM , Cornelia Huck , David Hildenbrand , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , linux-s390 , Michael Mueller , Vasily Gorbik , Andrea Arcangeli , linux-mm@kvack.org, Will Deacon , Sean Christopherson Subject: [PATCH v2 40/42] example for future extension: mm:gup/writeback: add callbacks for inaccessible pages: source indication Date: Fri, 14 Feb 2020 17:26:56 -0500 Message-Id: <20200214222658.12946-41-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 suspectscore=2 clxscore=1015 mlxlogscore=999 lowpriorityscore=0 phishscore=0 priorityscore=1501 mlxscore=0 spamscore=0 bulkscore=0 adultscore=0 impostorscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002140165 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Claudio Imbrenda We might want to do different things depending on where we are coming from. Cc: Will Deacon Cc: Sean Christopherson Signed-off-by: Claudio Imbrenda [borntraeger@de.ibm.com: patch description] Signed-off-by: Christian Borntraeger --- include/linux/gfp.h | 8 +++++++- mm/gup.c | 4 ++-- mm/page-writeback.c | 2 +- 3 files changed, 10 insertions(+), 4 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index be2754841369..a15fcb361e7c 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -485,8 +485,14 @@ static inline void arch_free_page(struct page *page, int order) { } #ifndef HAVE_ARCH_ALLOC_PAGE static inline void arch_alloc_page(struct page *page, int order) { } #endif +enum access_type { + MAKE_ACCESSIBLE_GENERIC, + MAKE_ACCESSIBLE_GET, + MAKE_ACCESSIBLE_GET_FAST, + MAKE_ACCESSIBLE_WRITEBACK +}; #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE -static inline int arch_make_page_accessible(struct page *page) +static inline int arch_make_page_accessible(struct page *page, int where) { return 0; } diff --git a/mm/gup.c b/mm/gup.c index 354bcfbd844b..ce962c155724 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -274,7 +274,7 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, page = ERR_PTR(-ENOMEM); goto out; } - ret = arch_make_page_accessible(page); + ret = arch_make_page_accessible(page, MAKE_ACCESSIBLE_GET); if (ret) { put_page(page); page = ERR_PTR(ret); @@ -1923,7 +1923,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, VM_BUG_ON_PAGE(compound_head(page) != head, page); - ret = arch_make_page_accessible(page); + ret = arch_make_page_accessible(page, MAKE_ACCESSIBLE_GET_FAST); if (ret) { put_page(head); goto pte_unmap; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 558d7063c117..f85148e59800 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2811,7 +2811,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write) * If writeback has been triggered on a page that cannot be made * accessible, it is too late. */ - WARN_ON(arch_make_page_accessible(page)); + WARN_ON(arch_make_page_accessible(page, MAKE_ACCESSIBLE_WRITEBACK)); return ret; }