From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933261AbbIYVB6 (ORCPT ); Fri, 25 Sep 2015 17:01:58 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:24046 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755366AbbIYVB5 (ORCPT ); Fri, 25 Sep 2015 17:01:57 -0400 Message-ID: <5605B5DA.2030402@oracle.com> Date: Fri, 25 Sep 2015 17:00:10 -0400 From: Boris Ostrovsky User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Konrad Rzeszutek Wilk CC: Vitaly Kuznetsov , xen-devel@lists.xenproject.org, x86@kernel.org, David Vrabel , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] xen/pvhvm: add soft reset on kexec/kdump support References: <1443175192-4828-1-git-send-email-vkuznets@redhat.com> <20150925135937.GJ20966@l.oracle.com> <56056E1D.80307@oracle.com> <87si62pjnd.fsf@vitty.brq.redhat.com> <560581B4.3070107@oracle.com> <20150925190154.GC21231@l.oracle.com> <56059E5D.4000604@oracle.com> <20150925193541.GG21231@l.oracle.com> In-Reply-To: <20150925193541.GG21231@l.oracle.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/25/2015 03:35 PM, Konrad Rzeszutek Wilk wrote: > On Fri, Sep 25, 2015 at 03:19:57PM -0400, Boris Ostrovsky wrote: >> On 09/25/2015 03:01 PM, Konrad Rzeszutek Wilk wrote: >>> On Fri, Sep 25, 2015 at 01:17:40PM -0400, Boris Ostrovsky wrote: >>>> On 09/25/2015 12:07 PM, Vitaly Kuznetsov wrote: >>>>>> Also, I am not sure I see how this new op will be used in the >>>>>> hypervisor --- currently AFAICS it is only processed under >>>>>> is_hardware_domain(). Are there other patches that will support HVM >>>>>> guests? >>>>> Please see my Xen series: >>>>> http://lists.xenproject.org/archives/html/xen-devel/2015-09/msg00547.html >>>>> (last 'full' submission). >>>>> >>>>> All patches from my 'toolstack-assisted approach to PVHVM guest kexec' >>>>> are already merged to xen.git (first 10 are already in 'master' and the >>>>> last one is in 'staging'). >>>>> >>>> OK, so I was looking at the right tree. Then I don't understand how >>>> SHUTDOWN_soft_reset would be reached for a non-privileged domain. The only >>>> path that I see is >>>> >>>> domain_shutdown() >>>> { >>>> ... >>>> if ( is_hardware_domain(d) ) >>>> hwdom_shutdown(reason); >>>> ... >>>> } >>>> >>>> Is there another path to handle this op? >>> Yes: >>> e1bd9812966de9a16f30a58e7162b80bd6af361b libxc: support XEN_DOMCTL_soft_reset operation >>> and >>> c57e6ebd8c3e490e353e68d96abec1dad01e72f5 (lib)xl: soft reset support >>> >> >> That's toolstack issuing hypercalls from dom0. >> >> I am asking about (non-privileged) guest itself calling SCHEDOP_shutdown. > The hypervisor ends up calling: > __domain_finalise_shutdown which sends an VIRQ_DOM_EXC to dom0 which > makes the toolstack do all of those operations. OK. But the I don't see anyone checking that 'reason' (or 'shutdown_code') is SHUTDOWN_soft_reset. In other words, the guest can do 'xen_reboot(23)' or 'xen_reboot(154)'. Or, it seems, even 'xen_reboot(SHUTDOWN_reboot)'? The only value it shouldn't be is SHUTDOWN_suspend. -boris