KVM: PMU: warn when pin control is set in eventsel msr

Print warning once if pin control bit is set in eventsel msr since
emulation does not support it yet.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/include/asm/perf_event.h

@@ -23,6 +23,7 @@
 #define ARCH_PERFMON_EVENTSEL_USR			(1ULL << 16)
 #define ARCH_PERFMON_EVENTSEL_OS			(1ULL << 17)
 #define ARCH_PERFMON_EVENTSEL_EDGE			(1ULL << 18)
+#define ARCH_PERFMON_EVENTSEL_PIN_CONTROL		(1ULL << 19)
 #define ARCH_PERFMON_EVENTSEL_INT			(1ULL << 20)
 #define ARCH_PERFMON_EVENTSEL_ANY			(1ULL << 21)
 #define ARCH_PERFMON_EVENTSEL_ENABLE			(1ULL << 22)

arch/x86/kvm/pmu.c

@@ -210,6 +210,9 @@ static void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
 	unsigned config, type = PERF_TYPE_RAW;
 	u8 event_select, unit_mask;
 
+	if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL)
+		printk_once("kvm pmu: pin control bit is ignored\n");
+
 	pmc->eventsel = eventsel;
 
 	stop_counter(pmc);