diff options
Diffstat (limited to 'kernel/arch/x86/kernel/pvclock.c')
-rw-r--r-- | kernel/arch/x86/kernel/pvclock.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/arch/x86/kernel/pvclock.c b/kernel/arch/x86/kernel/pvclock.c index 2f355d229..bf0ce7573 100644 --- 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)) { |