From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754110Ab2HaPPI (ORCPT ); Fri, 31 Aug 2012 11:15:08 -0400 Received: from am1ehsobe006.messaging.microsoft.com ([213.199.154.209]:17850 "EHLO am1outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753614Ab2HaPPG convert rfc822-to-8bit (ORCPT ); Fri, 31 Aug 2012 11:15:06 -0400 X-Forefront-Antispam-Report: CIP:131.107.125.8;KIP:(null);UIP:(null);IPV:NLI;H:TK5EX14HUBC107.redmond.corp.microsoft.com;RD:none;EFVD:NLI X-SpamScore: -7 X-BigFish: VS-7(zz9371I542M1432Izz1202hzz8275bh8275dhz2fh2a8h683h839h944hd25hf0ah107ah1220h1155h) X-Forefront-Antispam-Report-Untrusted: CIP:157.56.234.5;KIP:(null);UIP:(null);(null);H:SN2PRD0310HT002.namprd03.prod.outlook.com;R:internal;EFV:INT From: KY Srinivasan To: Jason Wang , "devel@linuxdriverproject.org" , "linux-kernel@vger.kernel.org" , "Greg KH (gregkh@linuxfoundation.org)" CC: Haiyang Zhang Subject: RE: [PATCH] hv: vmbus_drv: detect hyperv through x86_hyper Thread-Topic: [PATCH] hv: vmbus_drv: detect hyperv through x86_hyper Thread-Index: AQHNhzsMve0qAkXkSUaRlwoBL73BRpd0B9oQ Date: Fri, 31 Aug 2012 15:14:44 +0000 Message-ID: <426367E2313C2449837CD2DE46E7EAF9309DDF86@SN2PRD0310MB382.namprd03.prod.outlook.com> References: <1346391164-34001-1-git-send-email-jasowang@redhat.com> In-Reply-To: <1346391164-34001-1-git-send-email-jasowang@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [173.61.55.165] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-OrganizationHeadersPreserved: SN2PRD0310HT002.namprd03.prod.outlook.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% X-FOPE-CONNECTOR: Id%59$Dn%REDHAT.COM$RO%2$TLS%6$FQDN%131.107.125.5$TlsDn% X-FOPE-CONNECTOR: Id%59$Dn%LINUXDRIVERPROJECT.ORG$RO%2$TLS%6$FQDN%131.107.125.5$TlsDn% X-FOPE-CONNECTOR: Id%59$Dn%VGER.KERNEL.ORG$RO%2$TLS%6$FQDN%131.107.125.5$TlsDn% X-FOPE-CONNECTOR: Id%59$Dn%LINUXFOUNDATION.ORG$RO%2$TLS%6$FQDN%131.107.125.5$TlsDn% X-CrossPremisesHeadersPromoted: TK5EX14HUBC107.redmond.corp.microsoft.com X-CrossPremisesHeadersFiltered: TK5EX14HUBC107.redmond.corp.microsoft.com X-OriginatorOrg: microsoft.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: Jason Wang [mailto:jasowang@redhat.com] > Sent: Friday, August 31, 2012 1:33 AM > To: devel@linuxdriverproject.org; linux-kernel@vger.kernel.org > Cc: Jason Wang; KY Srinivasan; Haiyang Zhang > Subject: [PATCH] hv: vmbus_drv: detect hyperv through x86_hyper > > There are two reasons we need to use x86_hyper instead of > query_hypervisor_presence(): > > - Not only hyperv but also other hypervisors such as kvm would set > X86_FEATURE_HYTPERVISOR, so query_hypervisor_presence() will return true > even > in kvm. This may cause extra delay of 5 seconds before failing the probing in > kvm guest. > - The hypervisor has been detected in init_hypervisor(), so no need to do the > work again. > > Cc: "K. Y. Srinivasan" > Cc: Haiyang Zhang > Signed-off-by: Jason Wang Thanks Jason. Acked-by: K. Y. Srinivasan > --- > drivers/hv/vmbus_drv.c | 25 ++----------------------- > 1 files changed, 2 insertions(+), 23 deletions(-) > > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index f40dd57..8e1a9ec 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -34,6 +34,7 @@ > #include > #include > #include > +#include > #include "hyperv_vmbus.h" > > > @@ -719,33 +720,11 @@ static struct acpi_driver vmbus_acpi_driver = { > }, > }; > > -/* > - * query_hypervisor_presence > - * - Query the cpuid for presence of windows hypervisor > - */ > -static int query_hypervisor_presence(void) > -{ > - unsigned int eax; > - unsigned int ebx; > - unsigned int ecx; > - unsigned int edx; > - unsigned int op; > - > - eax = 0; > - ebx = 0; > - ecx = 0; > - edx = 0; > - op = HVCPUID_VERSION_FEATURES; > - cpuid(op, &eax, &ebx, &ecx, &edx); > - > - return ecx & HV_PRESENT_BIT; > -} > - > static int __init hv_acpi_init(void) > { > int ret, t; > > - if (!query_hypervisor_presence()) > + if (x86_hyper != &x86_hyper_ms_hyperv) > return -ENODEV; > > init_completion(&probe_event); > -- > 1.7.1 > > >