On Tue, 28 Mar 2017, Liang, Kan wrote:
> > On Mon, 27 Mar 2017, kan.li...@intel.com wrote:
> > put_online_cpus();
> >
> > Aside of that, when this is set to SMI freeze, what causes a CPU which
> > comes online after that point to set the bit as well? Nothing AFAICT.
>
> I've patched the intel_pmu_cpu_starting.
> I think it guarantees that the new online CPU is set.
Only when the hotplug protection of the write is in place.....
> @@ -3174,6 +3174,11 @@ static void intel_pmu_cpu_starting(int cpu)
>
> cpuc->lbr_sel = NULL;
>
> + if (x86_pmu.attr_freeze_on_smi)
> + msr_set_bit_on_cpu(cpu, MSR_IA32_DEBUGCTLMSR,
> DEBUGCTLMSR_FREEZE_WHILE_SMM_BIT);
Can you please use brackets and line breaks?
Thanks,
tglx
