|
|
|
|
|
|
|
|
|
|
xen-devel
RE: [PATCH] vtdt: add a missing change (RE: [Xen-devel] Re: xen guest ha
To: |
Christoph Egger <Christoph.Egger@xxxxxxx> |
Subject: |
RE: [PATCH] vtdt: add a missing change (RE: [Xen-devel] Re: xen guest hang with TSC_DEADLINE) |
From: |
"Wei, Gang" <gang.wei@xxxxxxxxx> |
Date: |
Thu, 6 Jan 2011 09:35:45 +0800 |
Accept-language: |
zh-CN, en-US |
Acceptlanguage: |
zh-CN, en-US |
Cc: |
"xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, "Morgan, KeirX" <keirx.morgan@xxxxxxxxx>, Fraser <Keir.Fraser@xxxxxxxxxxxxx>, "Wei, Gang" <gang.wei@xxxxxxxxx> |
Delivery-date: |
Wed, 05 Jan 2011 17:36:17 -0800 |
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxxx |
In-reply-to: |
<201101051209.27540.Christoph.Egger@xxxxxxx> |
List-help: |
<mailto:xen-devel-request@lists.xensource.com?subject=help> |
List-id: |
Xen developer discussion <xen-devel.lists.xensource.com> |
List-post: |
<mailto:xen-devel@lists.xensource.com> |
List-subscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
List-unsubscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
References: |
<201012171529.56897.Christoph.Egger@xxxxxxx> <201101041200.22612.Christoph.Egger@xxxxxxx> <F26D193E20BBDC42A43B611D1BDEDE7125142296DA@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <201101051209.27540.Christoph.Egger@xxxxxxx> |
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
Thread-index: |
AcusyRAy07nw9Zy7ROKOEXHJzgnsagAdm0Bw |
Thread-topic: |
[PATCH] vtdt: add a missing change (RE: [Xen-devel] Re: xen guest hang with TSC_DEADLINE) |
Christoph Egger wrote on 2011-01-05:
>>>>>>> c/s 22529 and 22530 cause a xen guest hang.
>>>>>>>
>>>>>>> While "normal" guests like Linux and NetBSD boot fine I boot
>>>>>>> Xen itself as a xen guest for my nested virtualization.
>>>>>>>
>>>>>>> When I do that then the guest dom0 hangs at boot when it tries
>>>>>>> to initialize the first vcpu.
>>>>>>> The bug is introduced somewhere in c/s 22529 and triggers with
>>>>>>> c/s 22530.
>>>>>>
>>>>>> Can you enable apic_timer debug info var hvm_debug and give
>>>>>> more serial port log around the guest dom0 hangs? I used to
>>>>>> test xen guest, it works well expect that it boot a little bit slowly.
>>>>>
>>>>> This is the log output I get with TSC_DEADLINE feature enabled:
>>>>
>>>> Just found one change was missed while the whole patch was checked in.
>>>> Apply below patch, it should be ok now.
>>>> ...
>>> The hang is still reproducable with this change. Sorry.
>>
>> Can you still see below line in the serial log? Is there anything
>> different?
>>
>> (XEN) [HVM:1.0] <vlapic_tdt_msr_set> ignore tsc deadline msr write
>
> This one disappeared.
>
> My serial log is flooded with
>...
>
> But I never see a line starting with [HVM:1.0] or [HVM:1.4]. My guest
> has four virtual vcpus.
>
> nested dom0 output did not change.
I tried 4-vcpu guest on my 2-pcpu machine also. It can finally boot up although
it hangs for quite a long period (tens of minutes) while guest dom0 do starting
udev. It is similar as nested xen tdt=off case.
So it may caused by vendor specific code in dom0. I would like to propose a
easy workaround: expose tdt feature to guest on Intel platform only. Do you
agree? Or do you prefer to find the root cause of current issue?
Jimmy
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
|
|