2 files changed, 3 insertions, 1 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 225543bf45a5..97b023f0cbe8 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -106,6 +106,7 @@ config X86
         select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
         select GENERIC_TIME_VSYSCALL if X86_64
         select KTIME_SCALAR if X86_32
+        select ALWAYS_USE_PERSISTENT_CLOCK
         select GENERIC_STRNCPY_FROM_USER
         select GENERIC_STRNLEN_USER
         select HAVE_CONTEXT_TRACKING if X86_64
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 06ccb5073a3f..4b9ea101fe3b 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -623,7 +623,8 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
         ns_now = __cycles_2_ns(tsc_now);
 
         if (cpu_khz) {
-                *scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
+                *scale = ((NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR) +
+                                cpu_khz / 2) / cpu_khz;
                 *offset = ns_now - mult_frac(tsc_now, *scale,
                                              (1UL << CYC2NS_SCALE_FACTOR));
         }