From owner-svn-src-head@FreeBSD.ORG Thu Apr 24 00:27:35 2014 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 0FB6886D; Thu, 24 Apr 2014 00:27:35 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id F04201AB5; Thu, 24 Apr 2014 00:27:34 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.8/8.14.8) with ESMTP id s3O0RY4O023033; Thu, 24 Apr 2014 00:27:34 GMT (envelope-from grehan@svn.freebsd.org) Received: (from grehan@localhost) by svn.freebsd.org (8.14.8/8.14.8/Submit) id s3O0RY0x023032; Thu, 24 Apr 2014 00:27:34 GMT (envelope-from grehan@svn.freebsd.org) Message-Id: <201404240027.s3O0RY0x023032@svn.freebsd.org> From: Peter Grehan Date: Thu, 24 Apr 2014 00:27:34 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r264846 - head/sys/amd64/vmm/intel X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Apr 2014 00:27:35 -0000 Author: grehan Date: Thu Apr 24 00:27:34 2014 New Revision: 264846 URL: http://svnweb.freebsd.org/changeset/base/264846 Log: Allow the guest to read the TSC via MSR 0x10. NetBSD/amd64 does this, as does Linux on AMD CPUs. Reviewed by: neel MFC after: 3 weeks Modified: head/sys/amd64/vmm/intel/vmx.c Modified: head/sys/amd64/vmm/intel/vmx.c ============================================================================== --- head/sys/amd64/vmm/intel/vmx.c Wed Apr 23 23:13:46 2014 (r264845) +++ head/sys/amd64/vmm/intel/vmx.c Thu Apr 24 00:27:34 2014 (r264846) @@ -863,6 +863,11 @@ vmx_vminit(struct vm *vm, pmap_t pmap) * MSR_EFER is saved and restored in the guest VMCS area on a * VM exit and entry respectively. It is also restored from the * host VMCS area on a VM exit. + * + * The TSC MSR is exposed read-only. Writes are disallowed as that + * will impact the host TSC. + * XXX Writes would be implemented with a wrmsr trap, and + * then modifying the TSC offset in the VMCS. */ if (guest_msr_rw(vmx, MSR_GSBASE) || guest_msr_rw(vmx, MSR_FSBASE) || @@ -870,7 +875,8 @@ vmx_vminit(struct vm *vm, pmap_t pmap) guest_msr_rw(vmx, MSR_SYSENTER_ESP_MSR) || guest_msr_rw(vmx, MSR_SYSENTER_EIP_MSR) || guest_msr_rw(vmx, MSR_KGSBASE) || - guest_msr_rw(vmx, MSR_EFER)) + guest_msr_rw(vmx, MSR_EFER) || + guest_msr_ro(vmx, MSR_TSC)) panic("vmx_vminit: error setting guest msr access"); /*