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From:   Jim Mattson <jmattson@google.com>
Date:   Wed, 2 Jan 2019 15:26:56 -0800
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Subject: Re: [PATCH v4 04/10] KVM/x86: intel_pmu_lbr_enable
To:     Wei Wang <wei.w.wang@intel.com>
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        kvm list <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
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        Kan Liang <kan.liang@intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
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On Wed, Dec 26, 2018 at 2:01 AM Wei Wang <wei.w.wang@intel.com> wrote:
>
> The lbr stack is architecturally specific, for example, SKX has 32 lbr
> stack entries while HSW has 16 entries, so a HSW guest running on a SKX
> machine may not get accurate perf results. Currently, we forbid the
> guest lbr enabling when the guest and host see different lbr stack
> entries.

How do you handle live migration?