From patchwork Fri Apr 16 15:40:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A . Shutemov" X-Patchwork-Id: 12207995 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F41F3C43600 for ; Fri, 16 Apr 2021 15:41:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DDEA9613B0 for ; Fri, 16 Apr 2021 15:41:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343927AbhDPPmE (ORCPT ); Fri, 16 Apr 2021 11:42:04 -0400 Received: from mga12.intel.com ([192.55.52.136]:63662 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243449AbhDPPmC (ORCPT ); Fri, 16 Apr 2021 11:42:02 -0400 IronPort-SDR: MYQ5WHyWqi4eq+RLtc6h6T4PyD0VKMaSLilimbbgxNgZZutgsEAI09n4yxvFYXhWhMHHgxmLYj 0LnP85YfLcrA== X-IronPort-AV: E=McAfee;i="6200,9189,9956"; a="174550437" X-IronPort-AV: E=Sophos;i="5.82,226,1613462400"; d="scan'208";a="174550437" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Apr 2021 08:41:37 -0700 IronPort-SDR: pd4rjOuDB7GQ8SDPFXTAOT408W4GzC6bMM/6th6kYTROmgUGT42oXh6q1tqsLOgM51ZsWI2pcP 85QBOIF9XVfw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,226,1613462400"; d="scan'208";a="453378439" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga002.fm.intel.com with ESMTP; 16 Apr 2021 08:41:32 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id DF99D1D2; Fri, 16 Apr 2021 18:41:49 +0300 (EEST) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra , Sean Christopherson , Jim Mattson Cc: David Rientjes , "Edgecombe, Rick P" , "Kleen, Andi" , "Yamahata, Isaku" , Erdem Aktas , Steve Rutherford , Peter Gonda , David Hildenbrand , x86@kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [RFCv2 03/13] x86/kvm: Make DMA pages shared Date: Fri, 16 Apr 2021 18:40:56 +0300 Message-Id: <20210416154106.23721-4-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210416154106.23721-1-kirill.shutemov@linux.intel.com> References: <20210416154106.23721-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Make force_dma_unencrypted() return true for KVM to get DMA pages mapped as shared. __set_memory_enc_dec() now informs the host via hypercall if the state of the page has changed from shared to private or back. Signed-off-by: Kirill A. Shutemov --- arch/x86/Kconfig | 1 + arch/x86/mm/mem_encrypt_common.c | 5 +++-- arch/x86/mm/pat/set_memory.c | 10 ++++++++++ include/uapi/linux/kvm_para.h | 1 + 4 files changed, 15 insertions(+), 2 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 2b4ce1722dbd..d197b3beb904 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -811,6 +811,7 @@ config KVM_GUEST select PARAVIRT_CLOCK select ARCH_CPUIDLE_HALTPOLL select X86_HV_CALLBACK_VECTOR + select X86_MEM_ENCRYPT_COMMON default y help This option enables various optimizations for running under the KVM diff --git a/arch/x86/mm/mem_encrypt_common.c b/arch/x86/mm/mem_encrypt_common.c index dd791352f73f..6bf0718bb72a 100644 --- a/arch/x86/mm/mem_encrypt_common.c +++ b/arch/x86/mm/mem_encrypt_common.c @@ -10,14 +10,15 @@ #include #include #include +#include /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ bool force_dma_unencrypted(struct device *dev) { /* - * For SEV, all DMA must be to unencrypted/shared addresses. + * For SEV and KVM, all DMA must be to unencrypted/shared addresses. */ - if (sev_active()) + if (sev_active() || kvm_mem_protected()) return true; /* diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index 16f878c26667..4b312d80033d 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -1977,6 +1978,15 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) struct cpa_data cpa; int ret; + if (kvm_mem_protected()) { + /* TODO: Unsharing memory back */ + if (WARN_ON_ONCE(enc)) + return -ENOSYS; + + return kvm_hypercall2(KVM_HC_MEM_SHARE, + __pa(addr) >> PAGE_SHIFT, numpages); + } + /* Nothing to do if memory encryption is not active */ if (!mem_encrypt_active()) return 0; diff --git a/include/uapi/linux/kvm_para.h b/include/uapi/linux/kvm_para.h index 1a216f32e572..09d36683ee0a 100644 --- a/include/uapi/linux/kvm_para.h +++ b/include/uapi/linux/kvm_para.h @@ -30,6 +30,7 @@ #define KVM_HC_SEND_IPI 10 #define KVM_HC_SCHED_YIELD 11 #define KVM_HC_ENABLE_MEM_PROTECTED 12 +#define KVM_HC_MEM_SHARE 13 /* * hypercalls use architecture specific