From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 EC604C3F2D7 for ; Tue, 3 Mar 2020 13:04:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BF6CF20866 for ; Tue, 3 Mar 2020 13:04:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="vKKgzJDU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729287AbgCCNEN (ORCPT ); Tue, 3 Mar 2020 08:04:13 -0500 Received: from mail-wr1-f68.google.com ([209.85.221.68]:34168 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729180AbgCCNEM (ORCPT ); Tue, 3 Mar 2020 08:04:12 -0500 Received: by mail-wr1-f68.google.com with SMTP id z15so4278302wrl.1 for ; Tue, 03 Mar 2020 05:04:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=E8xR3t38FXzlVhdbvr87OuefY/3S2ns33WKM8IRdgPo=; b=vKKgzJDU9ZIuhu3qJ6JVGkJOYxb3yelu8Qz8cGUtxPIUDvL0vorqc2R/V+PGM84akK t8pFYm3Zn/ocnL00+B6IYuQm0NHDABLY3no6dVf4tMIxBbKzzkTxcN+o9UFtf5N2aasr Bw9G1p2kCmVDEUANqn/6ElBMo7BhosJBBRHfsIbQUe4w76tkmPUlwVrj5T5GWeg7mGY5 a0kzNoTu5sBKiGVUKM2t61jXCEUaDbP/S5gXkCIAZI6WviXYB4uFq4sDMW/J4dHaxqcC x9DoOgsdHlCJIOOfdTDRsVl0QgucL8j/7YqyZkg80Iws7nqvjbIjcIP/5ySXXLarDLBS NTlQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=E8xR3t38FXzlVhdbvr87OuefY/3S2ns33WKM8IRdgPo=; b=B+7G2B9H6SSzYOvnX1hrlVEjSZJyunNj+B64ZhtsSpSvOYskAxXRguhWfrt6DUTPF2 p1Ay86i0SPM9igv/3brTmFTMCkS63gan/us1gKHY2AgKKlCKBWp/FvqO62u2YRCqcPkm ebKAA7kKsWlBPfXlHeATl3lPYblXieWtdtIiUike8/ZbVLEd+/67nanoJnPT2A4spdzw RO5+/JypnR4lzFmPR0/TIQL2qOzhYp0Z4y1JSloHVcBfuILeNViZfosEqdHj2TZkFrFW 5sSSxsaOyYcVemgpPPV6EgaLxAMyBdQ5hRG38GJyABs9xxnmWubqN58mRs9rKgBKGZfY NUpQ== X-Gm-Message-State: ANhLgQ2oCYQXjaBH5GyDhEBs5UJSW4kSQQhRz1wd/nBvbkXShmvfC944 NLtpCBOyOgflEZlhXxZOekhQF+2V X-Google-Smtp-Source: ADFU+vsLRyFOSDd/yizaL7a5jAm78hnFQvxT35NziY1zavfOA4jIgy47QcrVLd0CzGN3a6zmDbkjwg== X-Received: by 2002:a5d:66c6:: with SMTP id k6mr5502163wrw.343.1583240650788; Tue, 03 Mar 2020 05:04:10 -0800 (PST) Received: from linux.local ([199.203.162.213]) by smtp.gmail.com with ESMTPSA id w17sm2171951wrm.92.2020.03.03.05.04.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Mar 2020 05:04:10 -0800 (PST) From: Jon Doron To: kvm@vger.kernel.org Cc: vkuznets@redhat.com, Jon Doron Subject: [PATCH v1 2/3] x86/kvm/hyper-v: enable hypercalls regardless of hypercall page Date: Tue, 3 Mar 2020 15:03:55 +0200 Message-Id: <20200303130356.50405-3-arilou@gmail.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200303130356.50405-1-arilou@gmail.com> References: <20200303130356.50405-1-arilou@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Microsoft's kdvm.dll dbgtransport module does not respect the hypercall page and simply identifies the CPU being used (AMD/Intel) and according to it simply makes hypercalls with the relevant instruction (vmmcall/vmcall respectively). The relevant function in kdvm is KdHvConnectHypervisor which first checks if the hypercall page has been enabled via HV_X64_MSR_HYPERCALL_ENABLE, and in case it was not it simply sets the HV_X64_MSR_GUEST_OS_ID to 0x1000101010001 which means: build_number = 0x0001 service_version = 0x01 minor_version = 0x01 major_version = 0x01 os_id = 0x00 (Undefined) vendor_id = 1 (Microsoft) os_type = 0 (A value of 0 indicates a proprietary, closed source OS) and starts issuing the hypercall without setting the hypercall page. To resolve this issue simply enable hypercalls if the guest_os_id is not 0. Signed-off-by: Jon Doron --- arch/x86/kvm/hyperv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 13176ec23496..7ec962d433af 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1615,7 +1615,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *current_vcpu, u64 ingpa, u64 outgpa, bool kvm_hv_hypercall_enabled(struct kvm *kvm) { - return READ_ONCE(kvm->arch.hyperv.hv_hypercall) & HV_X64_MSR_HYPERCALL_ENABLE; + return READ_ONCE(kvm->arch.hyperv.hv_guest_os_id) != 0; } static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result) -- 2.24.1