Re: [PATCH 0/2] Put AP into safe hlt-loop code on S3 path

[Laszlo Ersek <lersek@redhat.com>]

On 11/10/16 13:26, Paolo Bonzini wrote:
> 
> 
> On 10/11/2016 11:41, Laszlo Ersek wrote:
>> Here's an excerpt from the KVM trace:
>>
>>>  CPU-23509 [002]  8406.908787: kvm_enter_smm:        vcpu 1: entering SMM, smbase 0x30000
>>>  CPU-23509 [002]  8406.908836: kvm_enter_smm:        vcpu 1: leaving SMM, smbase 0x7ffb3000
>>>  CPU-23510 [003]  8406.908850: kvm_enter_smm:        vcpu 2: entering SMM, smbase 0x30000
>>>  CPU-23510 [003]  8406.908881: kvm_enter_smm:        vcpu 2: leaving SMM, smbase 0x7ffb5000
>>>  CPU-23511 [001]  8406.908908: kvm_enter_smm:        vcpu 3: entering SMM, smbase 0x30000
>>>  CPU-23511 [001]  8406.908941: kvm_enter_smm:        vcpu 3: leaving SMM, smbase 0x7ffb7000
>>>  CPU-23508 [005]  8406.908951: kvm_enter_smm:        vcpu 0: entering SMM, smbase 0x30000
>>>  CPU-23508 [005]  8406.908989: kvm_enter_smm:        vcpu 0: leaving SMM, smbase 0x7ffb1000
>>>  CPU-23511 [001]  8406.920215: kvm_enter_smm:        vcpu 3: entering SMM, smbase 0x7ffb7000
>>>  CPU-23509 [002]  8406.920225: kvm_enter_smm:        vcpu 1: entering SMM, smbase 0x7ffb3000
>>>  CPU-23510 [003]  8406.920225: kvm_enter_smm:        vcpu 2: entering SMM, smbase 0x7ffb5000
>>>  CPU-23508 [005]  8406.920227: kvm_enter_smm:        vcpu 0: entering SMM, smbase 0x7ffb1000
>>>  CPU-23508 [005]  8406.920262: kvm_enter_smm:        vcpu 0: leaving SMM, smbase 0x7ffb1000
>>>  CPU-23511 [001]  8406.920263: kvm_enter_smm:        vcpu 3: leaving SMM, smbase 0x7ffb7000
>>>  CPU-23508 [005]  8407.020292: kvm_enter_smm:        vcpu 0: entering SMM, smbase 0x7ffb1000
>>>  CPU-23509 [006]  8407.020338: kvm_enter_smm:        vcpu 1: leaving SMM, smbase 0x7ffb3000
>>>  CPU-23510 [003]  8407.020338: kvm_enter_smm:        vcpu 2: leaving SMM, smbase 0x7ffb5000
>>>  CPU-23508 [005]  8407.020338: kvm_enter_smm:        vcpu 0: leaving SMM, smbase 0x7ffb1000
>>
>> It seems that VCPU#0 still leaves (and then re-enters) SMM while VCPU#1 and VCPU#2 are firmly in SMM.
>>
>> So this series is a clear improvement, but something else remains amiss.
>>
>> If I remove Jiewen's v2 series, and apply only this one, then the symptom shows up much less frequently, but it does exist:
>> - With (Jiewen's v2 + this one), testing case 13, I hit the symptom on the second resume,
>> - With just this set applied, I hit the symptom (= one AP disappearing from Linux after resume) only on the 24th resume.
> 
> Any trace I can look at?

Thank you for asking / offering, I did stash the full trace :), I just
didn't want to foist it upon you without you offering first :)

http://people.redhat.com/lersek/s3-crash-8d1dfed7-ca92-4e25-8d2b-b1c9ac2a53db/case-13-jiewen-v2-jeff-fixup-trace.txt.bz2

> What about case 14, with
> PcdCpuSmmStaticPageTable=TRUE?

I didn't test case 14, because I consider it a more demanding test case
than case 13. According to Jiewen's earlier explanation,
PcdCpuSmmStaticPageTable=FALSE implements a subset of the protections
that PcdCpuSmmStaticPageTable=TRUE implements.

Thanks
Laszlo