Re: [PATCH v3 1/7] KVM: x86/pmu: Avoid setting BIT_ULL(-1) to pmu->host_cross_mapped_mask

From: Sean Christopherson
Date: Thu Sep 22 2022 - 18:31:21 EST


On Wed, Aug 31, 2022, Like Xu wrote:
> + hw_idx = pmc->perf_event->hw.idx;
> + /* make it a little less dependent on perf's exact behavior */

Reworded this to explain how a negative value can be encountered.

> + if (hw_idx != pmc->idx && hw_idx > -1)
> + pmu->host_cross_mapped_mask |= BIT_ULL(hw_idx);
> }
> }