Re: [PATCH V6] perf: Reset the dirty counter to prevent the leak for an RDPMC task

[Peter Zijlstra]

On Tue, May 11, 2021 at 05:42:54PM -0400, Liang, Kan wrote:
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index 1574b70..8216acc 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -3851,7 +3851,7 @@ static void perf_event_context_sched_in(struct
> perf_event_context *ctx,
>  		cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
>  	perf_event_sched_in(cpuctx, ctx, task);
> 
> -	if (cpuctx->sched_cb_usage && pmu->sched_task)
> +	if (pmu->sched_task && (cpuctx->sched_cb_usage ||
> atomic_read(&pmu->sched_cb_usages)))
>  		pmu->sched_task(cpuctx->task_ctx, true);

Aside from the obvious whitespace issues; I think this should work.