From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932564AbbIYPz4 (ORCPT ); Fri, 25 Sep 2015 11:55:56 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:40597 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932539AbbIYPzy (ORCPT ); Fri, 25 Sep 2015 11:55:54 -0400 Message-ID: <56056E1D.80307@oracle.com> Date: Fri, 25 Sep 2015 11:54:05 -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 , Vitaly Kuznetsov CC: 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> In-Reply-To: <20150925135937.GJ20966@l.oracle.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit 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 09/25/2015 09:59 AM, Konrad Rzeszutek Wilk wrote: > On Fri, Sep 25, 2015 at 11:59:52AM +0200, Vitaly Kuznetsov wrote: >> Currently there is a number of issues preventing PVHVM Xen guests from >> doing successful kexec/kdump: >> - Bound event channels. >> - Registered vcpu_info. >> - PIRQ/emuirq mappings. >> - shared_info frame after XENMAPSPACE_shared_info operation. >> - Active grant mappings. >> Basically, newly booted kernel stumbles upon already set up Xen interfaces >> and there is no way to reestablish them. In Xen-4.7 a new feature called >> 'soft reset' is coming. A guest performing kexec/kdump operation is >> supposed to call SCHEDOP_shutdown hypercall with SHUTDOWN_soft_reset reason >> before jumping to new kernel. Hypervisor (with some help from toolstack) >> will do full domain cleanup (but keeping its memory and vCPU contexts >> intact) returning the guest to the state it had when it was first booted >> and thus allowing it to start over. >> >> Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is >> probably OK as by default all unknown shutdown reasons cause domain destroy >> with a message in toolstack log: >> 'Unknown shutdown reason code 5. Destroying domain.' >> which gives a clue to what the problem is and eliminates false >> expectations. >> >> Signed-off-by: Vitaly Kuznetsov > Reviewed-by: Konrad Rzeszutek Wilk > > with s/pvhvm/hvm/ > > to match with the rest of the file. > > Thanks. >> >> +#ifdef CONFIG_KEXEC_CORE >> +static void xen_pvhvm_kexec_shutdown(void) >> +{ >> + native_machine_shutdown(); >> + if (kexec_in_progress) >> + xen_reboot(SHUTDOWN_soft_reset); >> +} This routine is not kexec-specific so "kexec_" should be dropped from the name. 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? -boris