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From:   Eric Hankland <ehankland@google.com>
Date:   Wed, 29 Jan 2020 17:09:56 -0800
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Subject: Re: [PATCH] KVM: x86: Fix perfctr WRMSR for running counters
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Jim Mattson <jmattson@google.com>, Peter Shier <pshier@google.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
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Sorry - I forgot to switch to plain text mode on my first reply.

> I think this best written as it was before commit 2924b52117:
>
>                         if (!msr_info->host_initiated)
>                                 data = (s64)(s32)data;
>                         pmc->counter += data - pmc_read_counter(pmc);
Sounds good to me.

> Do you have a testcase?
I added a testcase to kvm-unit-tests/x86/pmu.c that fails without this
patch and passes with it.
Should I send out that patch now?