Re: Windows 7 VM BSOD

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

>since they change the logic inside a function and never change
>function name, it's hard to tell by using nm kvm.ko as it only shows
>what function name included on kernel module.
>
Yes,
if you have the source, you can directly check it.,
otherwise, decompile kvm.ko, because apic_clear_isr() is inline function,
which is called by apic_set_eoi(), you can check it, this method is a bit complicated.
Any better ideas?

>On Thu, Dec 4, 2014 at 3:15 PM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>Is this the correct function?
>>>kvm_lapic_set_eoi
>>>
>> No, see the detail of commit fc57ac2c9ca,
>> https://git.kernel.org/cgit/virt/kvm/kvm.git/commit/arch/x86/kvm/lapic.c?id=fc57ac2c9ca8109ea97fcc594f4be436944230cc
>>
>>>I found that one tho.
>>>
>>>On Thu, Dec 4, 2014 at 2:22 PM, Thomas Lau <tlau@tetrioncapital.com> wrote:
>>>> I see, so it's minor performance gain, and not stability related
>>>> option which is good.
>>>>
>>>> I am checking http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.13.11.5-trusty/,
>>>> changelog showing lsr function is included, but when I download and
>>>> extract kvm.ko out then run nm kvm.ko | grep lsr, nothing found.
>>>>
>>>> On Thu, Dec 4, 2014 at 12:32 PM, Zhang Haoyu <zhanghy@sangfor.com> wrote:
>>>>>>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
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> 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