From patchwork Mon Nov 16 18:26:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 11910419 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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 3257DC4742C for ; Mon, 16 Nov 2020 18:33:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E41402231B for ; Mon, 16 Nov 2020 18:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732897AbgKPScm (ORCPT ); Mon, 16 Nov 2020 13:32:42 -0500 Received: from mga06.intel.com ([134.134.136.31]:20632 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387771AbgKPS2D (ORCPT ); Mon, 16 Nov 2020 13:28:03 -0500 IronPort-SDR: ZXajAuBrZ2koRQ28pD2moigbziGlX5TanRdDgllmNqAhUC1OpEKmBDabfHhaqe2DB2jd3nW74q oL90CDntHhzw== X-IronPort-AV: E=McAfee;i="6000,8403,9807"; a="232410028" X-IronPort-AV: E=Sophos;i="5.77,483,1596524400"; d="scan'208";a="232410028" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Nov 2020 10:28:02 -0800 IronPort-SDR: HSmSmve9NahGtLT9P0ekBHeZ+ETPGer5F6hFhlc8Q5AxThCCdr1jMH67bHx+ERS18CDjE7zU2t i7x5r3Jy1dHw== X-IronPort-AV: E=Sophos;i="5.77,483,1596524400"; d="scan'208";a="400527973" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Nov 2020 10:28:02 -0800 From: isaku.yamahata@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Sean Christopherson Subject: [RFC PATCH 22/67] KVM: Add per-VM flag to mark read-only memory as unsupported Date: Mon, 16 Nov 2020 10:26:07 -0800 Message-Id: <499bf4c92e07de7e27745cf8d266a1932d18d85f.1605232743.git.isaku.yamahata@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Isaku Yamahata Add a flag for TDX to flag RO memory as unsupported and propagate it to KVM_MEM_READONLY to allow reporting RO memory as unsupported on a per-VM basis. TDX1 doesn't expose permission bits to the VMM in the SEPT tables, i.e. doesn't support read-only private memory. Signed-off-by: Isaku Yamahata Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson --- arch/x86/kvm/x86.c | 4 +++- include/linux/kvm_host.h | 4 ++++ virt/kvm/kvm_main.c | 8 +++++--- 3 files changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 01380f057d9f..4060f3d91f74 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3695,7 +3695,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ASYNC_PF_INT: case KVM_CAP_GET_TSC_KHZ: case KVM_CAP_KVMCLOCK_CTRL: - case KVM_CAP_READONLY_MEM: case KVM_CAP_HYPERV_TIME: case KVM_CAP_IOAPIC_POLARITY_IGNORED: case KVM_CAP_TSC_DEADLINE_TIMER: @@ -3785,6 +3784,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) if (kvm_x86_ops.is_vm_type_supported(KVM_X86_TDX_VM)) r |= BIT(KVM_X86_TDX_VM); break; + case KVM_CAP_READONLY_MEM: + r = kvm && kvm->readonly_mem_unsupported ? 0 : 1; + break; default: break; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 95371750c23f..1a0df7b83fd0 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -517,6 +517,10 @@ struct kvm { pid_t userspace_pid; unsigned int max_halt_poll_ns; +#ifdef __KVM_HAVE_READONLY_MEM + bool readonly_mem_unsupported; +#endif + bool vm_bugged; }; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 3dc41b6e12a0..572a66a61c29 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1100,12 +1100,14 @@ static void update_memslots(struct kvm_memslots *slots, } } -static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem) +static int check_memory_region_flags(struct kvm *kvm, + const struct kvm_userspace_memory_region *mem) { u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES; #ifdef __KVM_HAVE_READONLY_MEM - valid_flags |= KVM_MEM_READONLY; + if (!kvm->readonly_mem_unsupported) + valid_flags |= KVM_MEM_READONLY; #endif if (mem->flags & ~valid_flags) @@ -1278,7 +1280,7 @@ int __kvm_set_memory_region(struct kvm *kvm, int as_id, id; int r; - r = check_memory_region_flags(mem); + r = check_memory_region_flags(kvm, mem); if (r) return r;