From patchwork Fri Aug 20 08:07:22 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zachary Amsden X-Patchwork-Id: 120550 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o7K8G7hg004483 for ; Fri, 20 Aug 2010 08:16:08 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751998Ab0HTIPX (ORCPT ); Fri, 20 Aug 2010 04:15:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21992 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751740Ab0HTIIT (ORCPT ); Fri, 20 Aug 2010 04:08:19 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o7K88EE6003183 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 20 Aug 2010 04:08:14 -0400 Received: from mysore (vpn-9-158.rdu.redhat.com [10.11.9.158]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o7K87qf2027969; Fri, 20 Aug 2010 04:08:12 -0400 From: Zachary Amsden To: kvm@vger.kernel.org Cc: Zachary Amsden , Avi Kivity , Marcelo Tosatti , Glauber Costa , Thomas Gleixner , John Stultz , linux-kernel@vger.kernel.org Subject: [KVM timekeeping 08/35] Warn about unstable TSC Date: Thu, 19 Aug 2010 22:07:22 -1000 Message-Id: <1282291669-25709-9-git-send-email-zamsden@redhat.com> In-Reply-To: <1282291669-25709-1-git-send-email-zamsden@redhat.com> References: <1282291669-25709-1-git-send-email-zamsden@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 20 Aug 2010 08:16:08 +0000 (UTC) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3420f25..5e3b10e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5457,6 +5457,10 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) { + if (check_tsc_unstable() && atomic_read(&kvm->online_vcpus) != 0) + printk_once(KERN_WARNING + "kvm: SMP vm created on host with unstable TSC; " + "guest TSC will not be reliable\n"); return kvm_x86_ops->vcpu_create(kvm, id); }