Re: [PATCH v6 08/16] KVM: x86/pmu: Add IA32_DS_AREA MSR emulation to support guest DS

[Andi Kleen]

On 5/17/2021 6:26 AM, Peter Zijlstra wrote:
> On Tue, May 11, 2021 at 10:42:06AM +0800, Like Xu wrote:
> > @@ -3897,6 +3898,8 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr, void *data)
> >   {
> >   	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
> >   	struct perf_guest_switch_msr *arr = cpuc->guest_switch_msrs;
> > +	struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
> > +	struct kvm_pmu *pmu = (struct kvm_pmu *)data;
> You can do without the cast, this is C, 'void *' silently casts to any
> other pointer type.

FWIW doing the C++ like casts for void * is fairly standard C coding 
style. I generally prefer it too for better documentation. K&R is 
written this way.

-Andi (my last email on this topic to avoid any bike shedding)