Previously, Ladi was working on enabling TSC page clocksource for nested
Hyper-V-on-KVM workloads. He found out that if Hyper-V frequency MSRs are
exposed to L1 as well as INVTSC flag Hyper-V enables TSC page clocksource
to its guests. Qemu doesn't pass INVTSC by default as it is a migration
blocker.

I found out there's a different way to make Hyper-V like us: expose
Reenlightenment MSRs to it. KVM doesn't fully support the feature as
we're still unable to migrate nested environments but rudimentary support
we have there (kvm/queue only currently) is enough.

Enable Hyper-V reenlightenment MSRs and expose frequency MSRs even without
INVTSC to make things work.

[My first patches for Qemu, please be nice :-) ]

Vitaly Kuznetsov (2):
  i386/kvm: add support for Hyper-V reenlightenment MSRs
  i386/kvm: lower requirements for Hyper-V frequency MSRs exposure

 target/i386/cpu.h          |  3 +++
 target/i386/hyperv-proto.h |  9 ++++++++-
 target/i386/kvm.c          | 35 ++++++++++++++++++++++++++++++++++-
 3 files changed, 45 insertions(+), 2 deletions(-)

-- 
2.14.3


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