diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index fe8110a8c75b..58419e50ff98 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -238,11 +238,11 @@ struct x86_pmu_capability {
 /*
  * We model BTS tracing as another fixed-mode PMC.
  *
- * We choose a value in the middle of the fixed event range, since lower
+ * We choose the value 47 for the fixed index of BTS, since lower
  * values are used by actual fixed events and higher values are used
  * to indicate other overflow conditions in the PERF_GLOBAL_STATUS msr.
  */
-#define INTEL_PMC_IDX_FIXED_BTS			(INTEL_PMC_IDX_FIXED + 16)
+#define INTEL_PMC_IDX_FIXED_BTS			(INTEL_PMC_IDX_FIXED + 15)
 
 #define GLOBAL_STATUS_COND_CHG			BIT_ULL(63)
 #define GLOBAL_STATUS_BUFFER_OVF_BIT		62