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=-9.6 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 69FB5C55191 for ; Fri, 24 Apr 2020 11:38:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 498B320776 for ; Fri, 24 Apr 2020 11:38:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WU7T8i2c" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727047AbgDXLiM (ORCPT ); Fri, 24 Apr 2020 07:38:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727031AbgDXLiL (ORCPT ); Fri, 24 Apr 2020 07:38:11 -0400 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1440AC09B049; Fri, 24 Apr 2020 04:38:11 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id k1so10412730wrx.4; Fri, 24 Apr 2020 04:38:10 -0700 (PDT) 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=185SwzLVVIfJjlMT/4T4W/sYUIKM9bGfdpVtPDHFNUM=; b=WU7T8i2cpxaKJ0kMdSrhB5lMKP1LVya8000lyNygTwbZe2FyR+mO1c57jwU2D7bndr pt3z2SEfs+gE9tenAwhIlrqz58+OG4djwOCufTJzXaQA89Mb7+4cER2dd1ong83/CnaL P4LjaMk5kf15wRf6bKa/mQ3n8IqxrlIBcX8Gp34Us9Qtlbkc/hWMr1t1L1CP4cE82Rga Dk1JRUKkH9f5VWrCBayfY3OI+NfbW3Vm9BTg7kvYTWMU6P54JJyic/RwIiuR4vU1LsGJ tZONzMcrKxoM5O44AeGsG3MMNV2UaTk2S4IsaeI57PlB7i7VXDTjPmmTQuo9J/xIn0Gn I0CA== 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=185SwzLVVIfJjlMT/4T4W/sYUIKM9bGfdpVtPDHFNUM=; b=eUYzftm4JqwAnpxEm+k36ZXuJmxe+5PRHbGJ/NAD2clEpVAPwwcDwaq2VWS+IYB7e0 1+kTjRrSMJaz8VeC2HyamtWY3zbZBQJ+aa1X3x7KObX0UCwjfgtcnJorzBgrZVLXGiMZ N6aGJKWjJe3HdmAWeajyYNLQLQ7OpiAbriNDTjoQJtNy/0TeF9Wo+3wr/keYLoDbRQcq ZJtv4mDtJUZgdFFrFIMTbl4M5/BupEKUDg5a+3ITevX3DzIQ9JjI08Q8IjezFs7WPU8L cqGJyxQqkenZztZ3PwfDTwaAVGWHRGIYifUen4nl20BtMj5FZmnQ95utaxOaYLNEuMIZ NYLw== X-Gm-Message-State: AGi0PuYEkikiuOxM2vpFT+t/eNi2GaMwnfI4OzEu9dbwXnyoVODjKLZL z4Hr1ylKpNxi3wir7mm3FJRisznfjHY= X-Google-Smtp-Source: APiQypLDULS/6aew41IS8CCwS3NKorbTXXOXLyi3VS2TYK1qLaSm2Z416IZp/SMRsglQ+nLurZO/Rw== X-Received: by 2002:a5d:480b:: with SMTP id l11mr11493982wrq.25.1587728288865; Fri, 24 Apr 2020 04:38:08 -0700 (PDT) Received: from jondnuc.lan (IGLD-84-229-154-20.inter.net.il. [84.229.154.20]) by smtp.gmail.com with ESMTPSA id w83sm2451007wmb.37.2020.04.24.04.38.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Apr 2020 04:38:08 -0700 (PDT) From: Jon Doron To: kvm@vger.kernel.org, linux-hyperv@vger.kernel.org Cc: vkuznets@redhat.com, Jon Doron Subject: [PATCH v11 5/7] x86/kvm/hyper-v: enable hypercalls without hypercall page with syndbg Date: Fri, 24 Apr 2020 14:37:44 +0300 Message-Id: <20200424113746.3473563-6-arilou@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200424113746.3473563-1-arilou@gmail.com> References: <20200424113746.3473563-1-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 also if the guest_os_id is not 0 and the syndbg feature is enabled. Reviewed-by: Vitaly Kuznetsov Signed-off-by: Jon Doron --- arch/x86/kvm/hyperv.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 435516595090..524b5466a515 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1650,7 +1650,10 @@ 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; + struct kvm_hv *hv = &kvm->arch.hyperv; + + return READ_ONCE(hv->hv_hypercall) & HV_X64_MSR_HYPERCALL_ENABLE || + (hv->hv_syndbg.active && READ_ONCE(hv->hv_guest_os_id) != 0); } static void kvm_hv_hypercall_set_result(struct kvm_vcpu *vcpu, u64 result) -- 2.24.1