From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753846AbdJCMy3 (ORCPT ); Tue, 3 Oct 2017 08:54:29 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:22759 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753594AbdJCMy0 (ORCPT ); Tue, 3 Oct 2017 08:54:26 -0400 Subject: Re: [PATCH v6 3/4] x86/xen/time: setup vcpu 0 time info page To: Joao Martins , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Juergen Gross , Andy Lutomirski References: <20171003115531.22546-1-joao.m.martins@oracle.com> <20171003115531.22546-4-joao.m.martins@oracle.com> From: Boris Ostrovsky Message-ID: Date: Tue, 3 Oct 2017 08:53:01 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20171003115531.22546-4-joao.m.martins@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/03/2017 07:55 AM, Joao Martins wrote: > In order to support pvclock vdso on xen we need to setup the time > info page for vcpu 0 and register the page with Xen using the > VCPUOP_register_vcpu_time_memory_area hypercall. This hypercall > will also forcefully update the pvti which will set some of the > necessary flags for vdso. Afterwards we check if it supports the > PVCLOCK_TSC_STABLE_BIT flag which is mandatory for having > vdso/vsyscall support. And if so, it will set the cpu 0 pvti that > will be later on used when mapping the vdso image. > > The xen headers are also updated to include the new hypercall for > registering the secondary vcpu_time_info struct. > > Signed-off-by: Joao Martins > Reviewed-by: Juergen Gross Reviewed-by: Boris Ostrovsky