Re: Windows 7 VM BSOD

["Zhang Haoyu" <zhanghy@sangfor.com>]

>what does vapic affect Windows 7 at all if I disable it? if it just a
>minor performance drop, I am fine with that.
>
hv_vapic provides accelerated MSR access to high usage memory mapped APIC
registers, EOI, ICR, TPR.
You can gain performance promotion from it, not too much,
but it also depends on the frequency of access to above three apic regs.

>On Thu, Dec 4, 2014 at 10:06 AM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>Sure, but I am little confused as KVM is part of linux kernel now, if
>>>I want to try it, should I just upgrade kernel or compile kvm kernel
>>>module by myself ?!
>>>
>> You can just apply the patch to kvm module and rebuild it.
>>
>>>On Thu, Dec 4, 2014 at 10:01 AM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>>>I just confirmed that vapic is causing win7 stuck.
>>>>>
>>>> You'd better try the commit fc57ac2c9ca :-)
>>>>
>>>>>On Thu, Dec 4, 2014 at 9:34 AM, Thomas Lau <tlau@tetrioncapital.com> wrote:
>>>>>> Hi,
>>>>>>
>>>>>> I don't want to recompile stuff, does it matter to have hv_vapic on at all?
>>>>>>
>>>>>> On Thu, Dec 4, 2014 at 9:24 AM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>>>>>> Oh I see,
>>>>>>>>
>>>>>>>> So 101 BSOD problem is well known? Can't find any document mention about 101 BSOD online.
>>>>>>>>
>>>>>>>> I tried to use hv_ other options but Win7 can't boot up properly and stucked at starting Windows screen.
>>>>>>>>
>>>>>>> Could you confirm that the stuck was caused by vhich hv feature?
>>>>>>> The commit fc57ac2c9ca can resolve a stuck caused by hv_vapic which I encountered before.
>>>>>>> https://git.kernel.org/cgit/virt/kvm/kvm.git/commit/arch/x86/kvm/lapic.c?id=fc57ac2c9ca8109ea97fcc594f4be436944230cc
>>>>>>>
>>>>>>>> Sent from my BlackBerry 10 smartphone.
>>>>>>>>   Original Message
>>>>>>>> From: Vadim Rozenfeld
>>>>>>>> Sent: Wednesday, 3 December, 2014 7:30 PM
>>>>>>>> To: Thomas Lau
>>>>>>>> Cc: Zhang Haoyu; kvm; imammedo
>>>>>>>> Subject: Re: Windows 7 VM BSOD
>>>>>>>>
>>>>>>>> If you run WS2008(R2) or Win7 - always turn on relaxed timing. Otherwise
>>>>>>>> it's just a matter of time when you hit 101 BOSD.
>>>>>>>> Bugcheck 78 is quite rare one. What is your setup, and how easy it's
>>>>>>>> reproducible?
>>>>>>>>
>>>>>>>> Best regards,
>>>>>>>> Vadim.
>>>>>>>>
>>>>>>>> On Wed, 2014-12-03 at 19:13 +0800, Thomas Lau wrote:
>>>>>>>> > "it works on your side" meaning that you had such issue but afterwards
>>>>>>>> > it's all fixed by apply hv_relaxed ?
>>>>>>>> >
>>>>>>>> > On Wed, Dec 3, 2014 at 7:08 PM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>>>>>> > >> https://bugzilla.redhat.com/show_bug.cgi?id=893857
>>>>>>>> > >>
>>>>>>>> > >> In fact I am doing testing now, but are we fixing one problem and
>>>>>>>> > >> introduce other problem?!
>>>>>>>> > >>
>>>>>>>> > > I'm not sure about this, but it works on my side,
>>>>>>>> > > I think BSOD(error:0x00000078) has been fixed,
>>>>>>>> > > please show your environment.
>>>>>>>> > >
>>>>>>>> > > Thanks,
>>>>>>>> > > Zhang Haoyu
>>>>>>>> > >> On Wed, Dec 3, 2014 at 6:36 PM, Thomas Lau <tlau@tetrioncapital.com> wrote:
>>>>>>>> > >> > Hi,
>>>>>>>> > >> >
>>>>>>>> > >> > How do I know if my qemu-kvm version support this?
>>>>>>>> > >> >
>>>>>>>> > >> > On Wed, Dec 3, 2014 at 6:25 PM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>>>>>> > >> >>> Hi All,
>>>>>>>> > >> >>>
>>>>>>>> > >> >>> I am running 3.13.0-24-generic kernel on Ubuntu 14, Windows 7 VM
>>>>>>>> > >> >>> installation was fine, but it does random reboot by itself, the error
>>>>>>>> > >> >>> code is 0x00000101, does anyone know how to fix this?
>>>>>>>> > >> >> Could you try hv_relaxed, like "-cpu kvm64,hv_relaxed".
>>>>>>>> > >> >>
>>>>>>>> > >> >> Thanks,
>>>>>>>> > >> >> Zhang Haoyu
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Thomas Lau
>>>>>> Director of Infrastructure
>>>>>> Tetrion Capital Limited
>>>>>>
>>>>>> Direct: +852-3976-8903
>>>>>> Mobile: +852-9323-9670
>>>>>> Address: 20/F, IFC 1, Central district, Hong Kong