Re: [Qemu-devel] How to configure QEMU to support APIC virtualization

[Li Qiang]

ddm <address@hidden> 于2019年8月5日周一 下午1:20写道：

> Hi,
>
> As i know, KVM is based on passthrough host cpu to implement
> full-virtualiztion,
> if host cpu doesn't support this feature, it's impossible to turn on this
> feature by KVM.
> Wheher there are another ways in QEMU to emulate this feature，such as
> emulate it based on pure software, not rely on hardware.
>
>
IIUC there is no APICv emulate.


Thanks,
Li Qiang



> Thanks!
>
>
> At 2019-08-05 12:42:55, "Li Qiang" <address@hidden> wrote:
>
>
>
> ddm <address@hidden> 于2019年8月5日周一 上午11:55写道：
>
>> Hi guys,
>>
>>
>> I have tried via modprobe kvmintel enable_apicv=Y  to adjust KVM
>> parameter, but it doesn't effect,  and
>> cat /sys/module/kvm_intel/parameters/enable_apicv always return "N".
>> I don't know how to configure KVM or QEMU to support APIC virtualizaion
>> feature?
>>
>>
> AFAICT APICv is hardware feature, but I still don't know accurately after
> which CPU support it.
> You may refer the code about 'enable_apicv' related code in kvm to see how
> to detect this capability.
>
> Thanks,
> Li Qiang
>
>
>>
>> My host infos are as follows:
>> Architecture:          x86_64
>> CPU op-mode(s):        32-bit, 64-bit
>> Byte Order:            Little Endian
>> CPU(s):                1
>> On-line CPU(s) list:   0
>> Thread(s) per core:    1
>> Core(s) per socket:    1
>> Socket(s):             1
>> NUMA node(s):          1
>> Vendor ID:             GenuineIntel
>> CPU family:            6
>> Model:                 142
>> Model name:            Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
>> Stepping:              10
>> CPU MHz:               2112.001
>> BogoMIPS:              4224.00
>> Virtualization:        VT-x
>> Hypervisor vendor:     VMware
>> Virtualization type:   full
>> L1d cache:             32K
>> L1i cache:             32K
>> L2 cache:              256K
>> L3 cache:              8192K
>> NUMA node0 CPU(s):     0
>> Flags:                 fpu vme de pse tsc msr pae mce cx8 apic sep mtrr
>> pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb
>> rdtscp lm constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc
>> cpuid pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe
>> popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm
>> 3dnowprefetch cpuid_fault invpcid_single pti ssbd ibrs ibpb stibp
>> tpr_shadow vnmi ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2
>> invpcid rtm rdseed adx smap xsaveopt arat flush_l1d arch_capabilities
>>
>>
>> Could you tell me how to configure it?
>>
>>
>> Thanks!
>>
>>
>
>
>