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Date: Wed, 14 Mar 2012 12:52:58 +0200
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Subject: Re: [Qemu-devel] [PATCH 0/2 v3] kvm: notify host when guest panicked
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To: Wen Congyang <wency@cn.fujitsu.com>
Cc: Gleb Natapov <gleb@redhat.com>, kvm list <kvm@vger.kernel.org>, Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel <qemu-devel@nongnu.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Amit Shah <amit.shah@redhat.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

On 03/14/2012 12:52 PM, Wen Congyang wrote:
> > 
> >> If so, is this channel visible to guest userspace? If the channle is visible to guest
> >> userspace, the program running in userspace may write the same message to the channel.
> > 
> > Access control is via permissions.  You can have udev scripts assign
> > whatever uid and gid to the port of your interest.  By default, all
> > ports are only accessible to the root user.
>
> We should also prevent root user writing message to this channel if it is
> used for panicked notification.
>

Why?  root can easily cause a panic.

-- 
error compiling committee.c: too many arguments to function