Re: HVM Migration of domU on Qemu-upstream DM causes stuck system clock with ACPI

[George Dunlap <george.dunlap@eu.citrix.com>]

On 31/05/13 11:54, George Dunlap wrote:
> On 31/05/13 09:34, Diana Crisan wrote:
>> George,
>> On 30/05/13 17:06, George Dunlap wrote:
>>> On 05/30/2013 04:55 PM, Diana Crisan wrote:
>>>> On 30/05/13 16:26, George Dunlap wrote:
>>>>> On Tue, May 28, 2013 at 4:06 PM, Diana Crisan <dcrisan@flexiant.com>
>>>>> wrote:
>>>>>> Hi,
>>>>>>
>>>>>>
>>>>>> On 26/05/13 09:38, Ian Campbell wrote:
>>>>>>> On Sat, 2013-05-25 at 11:18 +0100, Alex Bligh wrote:
>>>>>>>> George,
>>>>>>>>
>>>>>>>> --On 24 May 2013 17:16:07 +0100 George Dunlap
>>>>>>>> <George.Dunlap@eu.citrix.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>>> FWIW it's reproducible on every host h/w platform we've tried
>>>>>>>>>> (a total of 2).
>>>>>>>>> Do you see the same effects if you do a local-host migrate?
>>>>>>>> I hadn't even realised that was possible. That would have made 
>>>>>>>> testing
>>>>>>>> live
>>>>>>>> migrate easier!
>>>>>>> That's basically the whole reason it is supported ;-)
>>>>>>>
>>>>>>>> How do you avoid the name clash in xen-store?
>>>>>>> Most toolstacks receive the incoming migration into a domain named
>>>>>>> FOO-incoming or some such and then rename to FOO upon 
>>>>>>> completion. Some
>>>>>>> also rename the outgoing domain "FOO-migratedaway" towards the 
>>>>>>> end so
>>>>>>> that the bits of the final teardown which can safely happen 
>>>>>>> after the
>>>>>>> target have start can be done so.
>>>>>>>
>>>>>>> Ian.
>>>>>>>
>>>>>>>
>>>>>> I am unsure what I am doing wrong, but I cannot seem to be able 
>>>>>> to do a
>>>>>> localhost migrate.
>>>>>>
>>>>>> I created a domU using "xl create xl.conf" and once it fully 
>>>>>> booted I
>>>>>> issued
>>>>>> an "xl migrate 11 localhost". This fails and gives the output below.
>>>>>>
>>>>>> Would you please advise on how to get this working?
>>>>>>
>>>>>> Thanks,
>>>>>> Diana
>>>>>>
>>>>>>
>>>>>> root@ubuntu:~# xl migrate 11 localhost
>>>>>> root@localhost's password:
>>>>>> migration target: Ready to receive domain.
>>>>>> Saving to migration stream new xl format (info 0x0/0x0/2344)
>>>>>> Loading new save file <incoming migration stream> (new xl fmt info
>>>>>> 0x0/0x0/2344)
>>>>>>   Savefile contains xl domain config
>>>>>> xc: progress: Reloading memory pages: 53248/1048575 5%
>>>>>> xc: progress: Reloading memory pages: 105472/1048575 10%
>>>>>> libxl: error: libxl_dm.c:1280:device_model_spawn_outcome: domain 12
>>>>>> device
>>>>>> model: spawn failed (rc=-3)
>>>>>> libxl: error: libxl_create.c:1091:domcreate_devmodel_started: device
>>>>>> model
>>>>>> did not start: -3
>>>>>> libxl: error: libxl_dm.c:1311:libxl__destroy_device_model: Device 
>>>>>> Model
>>>>>> already exited
>>>>>> migration target: Domain creation failed (code -3).
>>>>>> libxl: error: libxl_utils.c:393:libxl_read_exactly: file/stream
>>>>>> truncated
>>>>>> reading ready message from migration receiver stream
>>>>>> libxl: info: libxl_exec.c:118:libxl_report_child_exitstatus: 
>>>>>> migration
>>>>>> target process [10934] exited with error status 3
>>>>>> Migration failed, resuming at sender.
>>>>>> xc: error: Cannot resume uncooperative HVM guests: Internal error
>>>>>> libxl: error: libxl.c:404:libxl__domain_resume: xc_domain_resume
>>>>>> failed for
>>>>>> domain 11: Success
>>>>> Aha -- I managed to reproduce this one as well.
>>>>>
>>>>> Your problem is the "vncunused=0" -- that's instructing qemu "You 
>>>>> must
>>>>> use this exact port for the vnc server".  But when you do the 
>>>>> migrate,
>>>>> that port is still in use by the "from" domain; so the qemu for the
>>>>> "to" domain can't get it, and fails.
>>>>>
>>>>> Obviously this should fail a lot more gracefully, but that's a bit of
>>>>> a lower-priority bug I think.
>>>>>
>>>>>   -George
>>>> Yes, I managed to get to the bottom of it too and got vms migrating on
>>>> localhost on our end.
>>>>
>>>> I can confirm I did get the clock stuck problem while doing a 
>>>> localhost
>>>> migrate.
>>>
>>> Does the script I posted earlier "work" for you (i.e., does it fail 
>>> after some number of migrations)?
>>>
>>
>> I left your script running throughout the night and it seems that it 
>> does not always catch the problem. I see the following:
>>
>> 1. vm has the clock stuck
>> 2. script is still running as it seems the vm is still ping-able.
>> 3. migration fails on the basis that the vm is does not ack the 
>> suspend request (see below).
>
> So I wrote a script to run "date", sleep for 2 seconds, and run "date" 
> a second time -- and eventually the *sleep* hung.
>
> The VM is still responsive, and I can log in; if I type "date" 
> manually successive times then I get an advancing clock, but if I type 
> "sleep 1" it just hangs.
>
> If you run "dmesg" in the guest, do you see the following line?
>
> CE: Reprogramming failure. Giving up

I think this must be it; on my other box, I got the following messages:

[  224.732083] PM: late freeze of devices complete after 3.787 msecs
[  224.736062] Xen HVM callback vector for event delivery is enabled
[  224.736062] Xen Platform PCI: I/O protocol version 1
[  224.736062] xen: --> irq=8, pirq=16
[  224.736062] xen: --> irq=12, pirq=17
[  224.736062] xen: --> irq=1, pirq=18
[  224.736062] xen: --> irq=6, pirq=19
[  224.736062] xen: --> irq=4, pirq=20
[  224.736062] xen: --> irq=7, pirq=21
[  224.736062] xen: --> irq=28, pirq=22
[  224.736062] ata_piix 0000:00:01.1: restoring config space at offset 
0x1 (was 0x2800001, writing 0x2800005)
[  224.736062] PM: early restore of devices complete after 5.854 msecs
[  224.739692] ata_piix 0000:00:01.1: setting latency timer to 64
[  224.739782] xen-platform-pci 0000:00:03.0: PCI INT A -> GSI 28 
(level, low) -> IRQ 28
[  224.746900] PM: restore of devices complete after 7.540 msecs
[  224.758612] Setting capacity to 16777216
[  224.758749] Setting capacity to 16777216
[  224.898426] ata2.01: NODEV after polling detection
[  224.900941] ata2.00: configured for MWDMA2
[  231.055978] CE: xen increased min_delta_ns to 150000 nsec
[  231.055986] hrtimer: interrupt took 14460 ns
[  247.893303] PM: freeze of devices complete after 2.168 msecs
[  247.893306] suspending xenstore...
[  247.896977] PM: late freeze of devices complete after 3.666 msecs
[  247.900067] Xen HVM callback vector for event delivery is enabled
[  247.900067] Xen Platform PCI: I/O protocol version 1
[  247.900067] xen: --> irq=8, pirq=16
[  247.900067] xen: --> irq=12, pirq=17
[  247.900067] xen: --> irq=1, pirq=18
[  247.900067] xen: --> irq=6, pirq=19
[  247.900067] xen: --> irq=4, pirq=20
[  247.900067] xen: --> irq=7, pirq=21
[  247.900067] xen: --> irq=28, pirq=22
[  247.900067] ata_piix 0000:00:01.1: restoring config space at offset 
0x1 (was 0x2800001, writing 0x2800005)
[  247.900067] PM: early restore of devices complete after 4.612 msecs
[  247.906454] ata_piix 0000:00:01.1: setting latency timer to 64
[  247.906558] xen-platform-pci 0000:00:03.0: PCI INT A -> GSI 28 
(level, low) -> IRQ 28
[  247.914770] PM: restore of devices complete after 8.762 msecs
[  247.926557] Setting capacity to 16777216
[  247.926661] Setting capacity to 16777216
[  248.066661] ata2.01: NODEV after polling detection
[  248.067326] CE: xen increased min_delta_ns to 225000 nsec
[  248.067344] CE: xen increased min_delta_ns to 337500 nsec
[  248.067361] CE: xen increased min_delta_ns to 506250 nsec
[  248.067378] CE: xen increased min_delta_ns to 759375 nsec
[  248.067396] CE: xen increased min_delta_ns to 1139062 nsec
[  248.067413] CE: xen increased min_delta_ns to 1708593 nsec
[  248.067428] CE: xen increased min_delta_ns to 2562889 nsec
[  248.067441] CE: xen increased min_delta_ns to 3844333 nsec
[  248.067453] CE: xen increased min_delta_ns to 4000000 nsec
[  248.067466] CE: Reprogramming failure. Giving up
[  248.068075] ata2.00: configured for MWDMA2

Note the "CE: xen increased min_delta_ns to 150000nsec" at 231 for the 
previous suspend, and now it's increasing it up to 4 milliseconds before 
giving up for this suspend.

Konrad, stefano, any idea what's going on here?

  -George