1 files changed, 3 insertions, 4 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_knc.c b/arch/x86/kernel/cpu/perf_event_knc.c
index 7c46bfdbc373..73bcfbdedd50 100644
--- a/arch/x86/kernel/cpu/perf_event_knc.c
+++ b/arch/x86/kernel/cpu/perf_event_knc.c
@@ -226,12 +226,11 @@ static __initconst struct x86_pmu knc_pmu = {
         .event_map              = knc_pmu_event_map,
         .max_events             = ARRAY_SIZE(knc_perfmon_event_map),
         .apic                   = 1,
-        .max_period             = (1ULL << 31) - 1,
+        .max_period             = (1ULL << 39) - 1,
         .version                = 0,
         .num_counters           = 2,
-        /* in theory 40 bits, early silicon is buggy though */
-        .cntval_bits            = 32,
-        .cntval_mask            = (1ULL << 32) - 1,
+        .cntval_bits            = 40,
+        .cntval_mask            = (1ULL << 40) - 1,
         .get_event_constraints  = x86_get_event_constraints,
         .event_constraints      = knc_event_constraints,
         .format_attrs           = intel_knc_formats_attr,