Re: [PATCH] x86/msr: add idle version of wrmsr trace

[Peter Zijlstra]

On Wed, Aug 24, 2022 at 08:48:33AM +0200, Peter Zijlstra wrote:
> diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
> index 3e101719689a..6e82b2df29cb 100644
> --- a/drivers/idle/intel_idle.c
> +++ b/drivers/idle/intel_idle.c
> @@ -187,12 +187,12 @@ static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
>  	int ret;
>  
>  	if (smt_active)
> -		wrmsrl(MSR_IA32_SPEC_CTRL, 0);
> +		__native_wrmsr(MSR_IA32_SPEC_CTRL, 0);
>  
>  	ret = __intel_idle(dev, drv, index);
>  
>  	if (smt_active)
> -		wrmsrl(MSR_IA32_SPEC_CTRL, spec_ctrl);
> +		__native_wrmsr(MSR_IA32_SPEC_CTRL, spec_ctrl);
>  
>  	return ret;
>  }

Clearly I should not be sending email before having wake-up-juice.. that
should of course be native_wrmsr(SPEC_CTRL, val, 0) etc..