On Thu, 27 Oct 2016, Andy Lutomirski wrote: > On Thu, Oct 27, 2016 at 4:15 AM, Thomas Gleixner <[email protected]> wrote: > Let's just do this right from day one: > > static void set_cpuid_faulting(bool on) > { > u64 msrval; > > DEBUG_LOCKS_WARN_ON(!irqs_disabled()); > > msrval = this_cpu_read(msr_misc_features_enables_shadow); > msrval &= CPUID_FAULT_ENABLE; > msrval |= (on << CPUID_FAULT_ENABLE_BIT); > this_cpu_write(msr_misc_features_enables_shadow, msrval); > wrmsrl(MSR_MISC_FEATURES_ENABLES, msrval); > } > > RDMSR may be considerably faster than WRMSR, but that doesn't mean it's > *fast*.
Good point!
