diff --git a/sys/dev/hwpmc/hwpmc_arm64.h b/sys/dev/hwpmc/hwpmc_arm64.h
--- a/sys/dev/hwpmc/hwpmc_arm64.h
+++ b/sys/dev/hwpmc/hwpmc_arm64.h
@@ -40,7 +40,6 @@
 
 #define	ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(R)	(-(R))
 #define	ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(P)	(-(P))
-#define	EVENT_ID_MASK	0xFF
 
 #ifdef _KERNEL
 /* MD extension for 'struct pmc' */
diff --git a/sys/dev/hwpmc/hwpmc_arm64.c b/sys/dev/hwpmc/hwpmc_arm64.c
--- a/sys/dev/hwpmc/hwpmc_arm64.c
+++ b/sys/dev/hwpmc/hwpmc_arm64.c
@@ -181,7 +181,9 @@
 	}
 	pe = a->pm_ev;
 
-	config = (pe & EVENT_ID_MASK);
+	config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
+	if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
+		return (EINVAL);
 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
 
 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);