From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: PV DomU running linux 3.17.3 causing xen-netback
 fatal error in Dom0
Date: Thu, 4 Dec 2014 15:53:22 +0000
Message-ID: <54808372.8090102@citrix.com>
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To: Anthony Wright <anthony@overnetdata.com>, David Vrabel <david.vrabel@citrix.com>
Cc: xen-devel@lists.xensource.com, Wei Liu <wei.liu2@citrix.com>, Ian Campbell <ian.campbell@citrix.com>
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On 04/12/14 15:36, Anthony Wright wrote:
>> On 01/12/14 14:22, David Vrabel wrote:
>> This VIF protocol is weird. The first slot contains a txreq with a
>> size
>> for the total length of the packet, subsequent slots have sizes for
>> that
>> fragment only.
>>
>> netback then has to calculate how long the first slot is, by
>> subtracting
>> all the size from the following slots.
>>
>> So something has gone wrong but it's not obvious what it is. Any
>> chance
>> you can dump the ring state when it happens?
> 
> We think we've worked out how to dump the ring state, please see below.

We need the full contents of the ring which isn't currently available
via debugfs and I haven't had time to put together a debug patch to make
it available.

David