Windows 2016 hangs after live migration and I do not known is this a windows issue or not

[邹烨]

I try to run windows 2016 with GPU so I enabled 'kvm hidden' feature and boot windows 2016 with UEFI.

When I test live migration, guest just lost response and only reboot could recover it.

I did some debug

kvm trace shows frequent msr_read of HV_X64_MSR_TIME_REF_COUNT:

<...>-41064 [000] .... 168733.114930: kvm_msr: msr_read 40000020 = 0xfb3c08a54

and the perf result by 'perf kvm --host stat live' shows too many MSR_READ operations:

13:02:10.174121

Analyze events for all VMs, all VCPUs:

  VM-EXIT    Samples  Samples%     Time%    Min Time    Max Time         Avg time

  MSR_READ       6022    78.14%    74.10%      0.71us  21778.22us     42.52us ( +-  17.16% )

  EXTERNAL_INTERRUPT       1494    19.38%    21.65%      0.53us  12810.58us     50.08us ( +-  29.22% )

  IO_INSTRUCTION        126     1.63%     1.16%     23.80us     51.45us     31.73us ( +-   1.56% )

  APIC_WRITE         26     0.34%     0.06%      3.23us     10.96us      8.39us ( +-   4.81% )

  EOI_INDUCED         20     0.26%     0.02%      1.93us      3.27us      2.63us ( +-   3.21% )

  EPT_MISCONFIG         19     0.25%     3.01%     29.30us   9795.61us    548.07us ( +-  93.74% )

Total Samples:7707, Total events handled time:345545.97us.

So I removed hv_time from the command (in libvirt, it is a clock named 'hypervclock') and then the migration

nerver failed

I just check the documents about qemu: https://qemu.readthedocs.io/en/latest/system/i386/hyperv.html

Does anyone know why there are so many timestamp related call?

Thanks

-AlanJager