FreeBSD 11 Stable on a Xen :: bridge0 crashing server

[SK]

On 20/01/2017 16:43, The Doctor wrote:
> On Fri, Jan 20, 2017 at 07:20:15PM +0300, Andrey V. Elsukov wrote:
>> On 20.01.2017 18:57, Trond Endrest??l wrote:
>>>> Here is the situation:
>>>> I have a VPS server from a well reputed provider (and they deserve the
>>>> reputation), running FreeBSD 11 stable x64 under Xen Full Virtualization
>>>> (HVM). I have the xn0 interface which is working fine. I intend to use VIMAGE,
>>>> so I compiled the kernel, added cloned_interface="bridge0" and restarted the
>>>> server. But as soon as I am attaching the xn0 to bridge0, the kernel is
>>>> panicking and the server restarting.
>>>> Any suggestion/pointer/test-instruction is highly appreciated.
>>> The code crashes at line 427 of sys/netinet/if_ether.c:
>>>
>>>    ARPSTAT_INC(txrequests);
>>>
>>> See
>>> https://svnweb.freebsd.org/base/stable/11/sys/netinet/if_ether.c?view=annotate#l427
>>>
>>> stable/11 has problems accounting the outgoing octets of any xn
>>> interface, although this isn't connected to your case.
>>>
>>> Just to rule out any uncertainty, try this patch:
>>>
>>> https://svnweb.freebsd.org/base?view=revision&revision=308126
>>>
>>> See PR 213439,
>>> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=213439
>>>
>>> Note, I'm not a developer nor a committer, just a humble sysadmin.
>> This problem is unrelated. ARP statistics is global and isn't related to
>> some specific interface. IMHO, the kernel panics due to missing VNET
>> context. As I see from the code in sys/dev/xen, it is not capable with
>> VIMAGE.
>>
>> -- 
>> WBR, Andrey V. Elsukov
> Still we need to address this issue!
>
> Even here in FreeBSD-11 stable I see crashing
> of the bhyve.
>
> What I need to help you is what is needed for running gdb ../bhyve ../bhyve.core
>
Apologies, but I might be missing something here. I am not trying to run 
bhyve, bhyve is not crashing. FreeBSD 11 in my case (FreeBSD 
testBox.test.domain 11.0-STABLE FreeBSD 11.0-STABLE #0 r312349: Fri Jan 
20 12:29:17 GMT 2017 
root at testBox.test.domain:/usr/obj/usr/src/sys/vnet-test  amd64) is 
running on a Xen HVM, and as I am trying to attach bridge0 to any 
interface (either xn0, or epair0a, or so on), the server is crashing and 
rebooting. I had the line ifconfig_bridge0="addm xn0 addm epair0a up" on 
the /etc/rc.conf , and the server went into an infinite crash-reboot loop.

What I would like to have, if possible, is running FreeBSD 11 stable on 
the server, use vnet/vimage for my jails so I can isolate each of them 
from one another.

Currently I am building world with the patch suggested by Trond (started 
that before I read the mail from Andrey). But if that is unlikely to 
bring a solution, that would mean most people on VPS with jails that are 
using Xen are going to suffer from any upgrade to 11 (or having new 
servers running 11) -- which is definitely undesirable.

If anyone would like me to run further test on the box, please let me 
know what you'd like me to run, and I can come back with the response. 
Having a reliable/stable solution is the objective from my end.

Thanks to all for your suggestions/comments.

Regards
SK