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Message-ID: <4F6079E7.7010608@cn.fujitsu.com>
Date: Wed, 14 Mar 2012 18:58:47 +0800
From: Wen Congyang <wency@cn.fujitsu.com>
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To: Avi Kivity <avi@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>,
        "Daniel P. Berrange" <berrange@redhat.com>,
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        KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        Jan Kiszka <jan.kiszka@siemens.com>, Gleb Natapov <gleb@redhat.com>
Subject: Re: [PATCH 0/2 v3] kvm: notify host when guest panicked
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At 03/14/2012 06:52 PM, Avi Kivity Wrote:
> 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.
> 

root user can write the same message to virtio-serial while the guest is running...

Thanks
Wen Congyang