Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / arch / x86 / kernel / pvclock.c

diff --git a/kernel/arch/x86/kernel/pvclock.c b/kernel/arch/x86/kernel/pvclock.c
index 2f355d2..bf0ce75 100644 (file)
--- a/kernel/arch/x86/kernel/pvclock.c
+++ b/kernel/arch/x86/kernel/pvclock.c
@@ -66,6 +66,8 @@ u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src)
 
        do {
                version = __pvclock_read_cycles(src, &ret, &flags);
+               /* Make sure that the version double-check is last. */
+               smp_rmb();
        } while ((src->version & 1) || version != src->version);
 
        return flags & valid_flags;
@@ -80,6 +82,8 @@ cycle_t pvclock_clocksource_read(struct pvclock_vcpu_time_info *src)
 
        do {
                version = __pvclock_read_cycles(src, &ret, &flags);
+               /* Make sure that the version double-check is last. */
+               smp_rmb();
        } while ((src->version & 1) || version != src->version);
 
        if (unlikely((flags & PVCLOCK_GUEST_STOPPED) != 0)) {