From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:47617)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <gleb@redhat.com>) id 1SeNjr-0001XW-60
	for qemu-devel@nongnu.org; Tue, 12 Jun 2012 05:50:20 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <gleb@redhat.com>) id 1SeNjl-0006CT-0q
	for qemu-devel@nongnu.org; Tue, 12 Jun 2012 05:50:14 -0400
Received: from mx1.redhat.com ([209.132.183.28]:46671)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <gleb@redhat.com>) id 1SeNjk-0006BZ-PG
	for qemu-devel@nongnu.org; Tue, 12 Jun 2012 05:50:08 -0400
Date: Tue, 12 Jun 2012 12:49:57 +0300
From: Gleb Natapov <gleb@redhat.com>
Message-ID: <20120612094957.GR580@redhat.com>
References: <4FB9E4CE.8060709@cn.fujitsu.com> <4FD6E5EC.3090802@cn.fujitsu.com>
	<4FD6F488.7090303@de.ibm.com> <4FD6FD3B.2090800@cn.fujitsu.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4FD6FD3B.2090800@cn.fujitsu.com>
Subject: Re: [Qemu-devel] [PATCH] kvm: notify host when guest panicked
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Wen Congyang <wency@cn.fujitsu.com>
Cc: kvm list <kvm@vger.kernel.org>, Jan Kiszka <jan.kiszka@siemens.com>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, qemu-devel <qemu-devel@nongnu.org>, Christian Borntraeger <borntraeger@de.ibm.com>, Avi Kivity <avi@redhat.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

On Tue, Jun 12, 2012 at 04:26:35PM +0800, Wen Congyang wrote:
> At 06/12/2012 03:49 PM, Christian Borntraeger Wrote:
> >>> We have three solutions to implement this feature:
> >>> 1. use vmcall
> >>> 2. use I/O port
> >>> 3. use virtio-serial.
> >>
> >>> We have decided to avoid touching hypervisor. The reason why I choose
> >>> choose the I/O port is:
> >>> 1. it is easier to implememt
> >>> 2. it does not depend any virtual device
> >>> 3. it can work when startint the kernel
> > 
> > Havent looked deeply into that, butz wouldnt kvm_hypercall0 also fulfill all of these
> > points? You just have to define the number for each architecture and then it should be 
> > possible to write a simple panic driver that works on all architectures.
> > 
> >>> --- a/include/linux/kvm_para.h
> >>> +++ b/include/linux/kvm_para.h
> >>> @@ -20,6 +20,14 @@
> >>>  #define KVM_HC_FEATURES			3
> >>>  #define KVM_HC_PPC_MAP_MAGIC_PAGE	4
> >>>  
> >>> +#define KVM_PV_PORT	(0x505UL)
> >>> +
> > 
> > ignoring the above, shouldnt a port number go into an architecture specific file?
> 
> I am not sure whether it should be put into an architecture specific file.
> 
Because PIO is x86 thing.

--
			Gleb.