diff options
| author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
|---|---|---|
| committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
| commit | 863981e96738983919de841ec669e157e6bdaeb0 (patch) | |
| tree | d6d89a12e7eb8017837c057935a2271290907f76 /arch/x86/kernel/pvclock.c | |
| parent | 8dec7c70575785729a6a9e6719a955e9c545bcab (diff) | |
Linux-libre 4.7.1-gnupck-4.7.1-gnu
Diffstat (limited to 'arch/x86/kernel/pvclock.c')
| -rw-r--r-- | arch/x86/kernel/pvclock.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c index 99bfc0251..06c58ce46 100644 --- a/arch/x86/kernel/pvclock.c +++ b/arch/x86/kernel/pvclock.c @@ -61,11 +61,16 @@ void pvclock_resume(void) u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src) { unsigned version; - cycle_t ret; u8 flags; do { - version = __pvclock_read_cycles(src, &ret, &flags); + version = src->version; + /* Make the latest version visible */ + smp_rmb(); + + flags = src->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 +85,8 @@ 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)) { |