From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] kvm: notify host when guest paniced Date: Wed, 29 Feb 2012 12:00:41 +0200 Message-ID: <4F4DF749.7060507@redhat.com> References: <4F4AF1FB.6000903@cn.fujitsu.com> <4F4CB926.6050600@redhat.com> <4F4D7F5E.5040202@cn.fujitsu.com> <4F4DF4C6.90609@redhat.com> <20120229095557.GE24600@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm list , qemu-devel , linux-kernel@vger.kernel.org, KAMEZAWA Hiroyuki To: Gleb Natapov Return-path: In-Reply-To: <20120229095557.GE24600@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org On 02/29/2012 11:55 AM, Gleb Natapov wrote: > > > > > > > How about using a virtio-serial channel for this? You can transfer any > > amount of information (including the dump itself). > > > Isn't it unreliable after the guest panicked? So is calling hypercalls, or dumping, or writing to the screen. Of course calling a hypercall is simpler and so is more reliable. > Having special kdump > kernel that transfers dump to a host via virtio-serial channel though > sounds interesting. May be that's what you mean. Yes. The "panic, starting dump" signal should be initiated by the panicking kernel though, in case the dump fails. -- error compiling committee.c: too many arguments to function From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030526Ab2B2KAv (ORCPT ); Wed, 29 Feb 2012 05:00:51 -0500 Received: from mx1.redhat.com ([209.132.183.28]:22154 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756553Ab2B2KAu (ORCPT ); Wed, 29 Feb 2012 05:00:50 -0500 Message-ID: <4F4DF749.7060507@redhat.com> Date: Wed, 29 Feb 2012 12:00:41 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Gleb Natapov CC: Wen Congyang , kvm list , KAMEZAWA Hiroyuki , "Daniel P. Berrange" , linux-kernel@vger.kernel.org, qemu-devel Subject: Re: [PATCH] kvm: notify host when guest paniced References: <4F4AF1FB.6000903@cn.fujitsu.com> <4F4CB926.6050600@redhat.com> <4F4D7F5E.5040202@cn.fujitsu.com> <4F4DF4C6.90609@redhat.com> <20120229095557.GE24600@redhat.com> In-Reply-To: <20120229095557.GE24600@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/29/2012 11:55 AM, Gleb Natapov wrote: > > > > > > > How about using a virtio-serial channel for this? You can transfer any > > amount of information (including the dump itself). > > > Isn't it unreliable after the guest panicked? So is calling hypercalls, or dumping, or writing to the screen. Of course calling a hypercall is simpler and so is more reliable. > Having special kdump > kernel that transfers dump to a host via virtio-serial channel though > sounds interesting. May be that's what you mean. Yes. The "panic, starting dump" signal should be initiated by the panicking kernel though, in case the dump fails. -- error compiling committee.c: too many arguments to function From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56404) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S2gL8-0007wc-Sj for qemu-devel@nongnu.org; Wed, 29 Feb 2012 05:00:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S2gL4-0006Zm-0X for qemu-devel@nongnu.org; Wed, 29 Feb 2012 05:00:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:3346) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S2gL3-0006ZZ-Oy for qemu-devel@nongnu.org; Wed, 29 Feb 2012 05:00:49 -0500 Message-ID: <4F4DF749.7060507@redhat.com> Date: Wed, 29 Feb 2012 12:00:41 +0200 From: Avi Kivity MIME-Version: 1.0 References: <4F4AF1FB.6000903@cn.fujitsu.com> <4F4CB926.6050600@redhat.com> <4F4D7F5E.5040202@cn.fujitsu.com> <4F4DF4C6.90609@redhat.com> <20120229095557.GE24600@redhat.com> In-Reply-To: <20120229095557.GE24600@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] kvm: notify host when guest paniced List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gleb Natapov Cc: kvm list , qemu-devel , linux-kernel@vger.kernel.org, KAMEZAWA Hiroyuki On 02/29/2012 11:55 AM, Gleb Natapov wrote: > > > > > > > How about using a virtio-serial channel for this? You can transfer any > > amount of information (including the dump itself). > > > Isn't it unreliable after the guest panicked? So is calling hypercalls, or dumping, or writing to the screen. Of course calling a hypercall is simpler and so is more reliable. > Having special kdump > kernel that transfers dump to a host via virtio-serial channel though > sounds interesting. May be that's what you mean. Yes. The "panic, starting dump" signal should be initiated by the panicking kernel though, in case the dump fails. -- error compiling committee.c: too many arguments to function