FreeBSD Alpha5 amd64 - Citrix Xen 6.2 problem

[Justin T. Gibbs]

On Oct 10, 2013, at 3:09 AM, Shanker Balan <mail at shankerbalan.net> wrote:

> 
> On 10-Oct-2013, at 1:37 PM, Shanker Balan <mail at shankerbalan.net> wrote:
> 
>> On 09-Oct-2013, at 8:06 PM, Mark Felder <feld at FreeBSD.org> wrote:
>> 
>>> On Wed, Oct 9, 2013, at 8:53, Roger Pau Monné wrote:
>>>> On 09/10/13 13:49, Mark Felder wrote:
>>>>> On Wed, Oct 9, 2013, at 2:46, Roger Pau Monné wrote:
>>>>>> On 09/10/13 08:18, Shanker Balan wrote:
>>>>>>> On 08-Oct-2013, at 9:19 PM, Mark Felder <feld at FreeBSD.org> wrote:
>>>>>>> 
>>>>>>>> On Tue, Oct 8, 2013, at 9:45, Josias L.G wrote:
>>>>>>>>> Problem with Citrix Xen 6.2 and install from ISO. The "solution" was
>>>>>>>>> remove cd-rom drive from virtual machine. Not possible now with xen
>>>>>>>>> default in GENERIC kernel.
>>>>>>>>> Message error: 
>>>>>>>>> run_interrupt_driven_hooks - still waiting after 300 seconds for
>>>>>>>>> xenbusb_nop_confighook_cb
>>>>>>>>> panic: run_interrupt_driven_config_hooks: waited too long
>>>>>>>>> 
>>>>>>>> 
>>>>>>>> I was going to test this soon... but you're right -- you probably can't
>>>>>>>> install FreeBSD 10 from ISO on Citrix XenServer because of this bug.
>>>>>>>> 
>>>>>>>> Can someone working on the xen bits test and maybe find a workaround?
>>>>>>> 
>>>>>>> The "xenbusb_nop_confighook_cb" issue is the only issue which I am aware
>>>>>>> of that prevents CloudStack/XenServer IaaS private clouds from offering
>>>>>>> FreeBSD 10 as a supported OS template. The "vbd-destroy" workaround is not
>>>>>>> possible as the ISO is attached to the VM instance during the installation.
>>>>>>> 
>>>>>>> A "please pretty please" request to @citrix R&D for the hopefully last fix
>>>>>>> to get FreeBSD 10 running on XenServer+CloudStack.
>>>>>>> 
>>>>>>> The earlier HyperV related panic on XenServer has been fixed in ALPHA5.
>>>>>> 
>>>>>> Hello,
>>>>>> 
>>>>>> I've taken a look into this and I'm afraid there's no easy way to
>>>>>> workaround it from FreeBSD. When Xen is detected all IDE devices are
>>>>>> disconnected, and there's no fine grained way to only disable IDE disks
>>>>>> and not cdrom devices.
>>>>>> 
>>>>>> Could you please contact your XenServer representative, and/or submit
>>>>>> this bug to xs-devel (xs-devel at lists.xenserver.org) mailing lists in
>>>>>> order to get this fixed on XenServer.
>>>>>> 
>>>>> 
>>>>> Citrix is aware of this as I've contacted several people there and this
>>>>> has been discussed both here and on the xs-devel list. There has to be
>>>>> something FreeBSD can do to work around this issue since Linux and
>>>>> NetBSD have no issues.
>>>> 
>>>> Linux and NetBSD have no issues because you probably only tried them on
>>>> PV mode, which doesn't exhibit this issue (also NetBSD doesn't have
>>>> PVHVM support, so it's quite clear it won't have this issue).
>>>> 
>>>>> As far as I'm aware the issue has been tracked
>>>>> down to badly behaving qemu in XenServer -- they don't use upstream qemu
>>>>> in XenServer (yet), and instead have their own fork. A future release is
>>>>> supposed to merge with upstream qemu.
>>>> 
>>>> The main problem here is that XenServer announces a PV block device on
>>>> xenstore (the cdrom), but then it seems like there's no backend to
>>>> handle it, so it hangs on the connection phase. IMHO the problem is not
>>>> with the device model (Qemu), but with the backend that should handle
>>>> this PV device.
>>>> 
>>>> Xen only allows you to either disable all IDE devices or none, so the
>>>> only possible solution I can think of is to not disable anything at all
>>>> and use the emulated devices, which will leave us with very poor
>>>> performance (unless I'm missing something, there's no way to only
>>>> disable disks but not cdroms).
>>>> 
>>>>> But the fact remains that this is a non-issue on Linux and NetBSD who
>>>>> handle this buggy virtual CDROM without any problems. There has to be
>>>>> some way we can add a quirk on our side so this device doesn't stop the
>>>>> entire boot process. If FreeBSD 10 is released without out-of-the-box
>>>>> support on the premier commercial Xen platform we'll be shooting
>>>>> ourselves in the foot and all of this work will be for naught. Amazon
>>>>> isn't the only Xen platform people use.
>>>> 
>>>> You can always use the pre-build VM images I guess (I have not tested
>>>> those, but I expect they should work fine under Xen).
>>>> 
>>>> ftp://ftp.nl.freebsd.org/pub/FreeBSD/snapshots/VM-IMAGES/20131007/10.0-ALPHA5/amd64/
>>>> 
>> 
>> This is way better. Having ready to import Xen images beats ISO installation
>> any day. Will try on my cloudstack setup later today.
> 
> I converted the QCOV image to VHD and have imported it into CloudStack. Instance
> created from the template also have the "xenbusb" issue at bootup.
> 
> Oh well.
> 
> Thanks for all the help.
> 
> Regards.
> @shankerbalan

The CDROM issue should be resolved in FreeBSD/head.  These fixes will be include
in 10.0-BETA2 as well as the first 11-CURRENT snapshot that should pop up in
the next day or two.  The snapshots are announced on the freebsd-snapshots
mailing list.

--
Justin