--- /dev/null
+From f55c07607a38f84b5c7e6066ee1cfe433fa5643c Mon Sep 17 00:00:00 2001
+From: John Stultz <john.stultz@linaro.org>
+Date: Wed, 11 Dec 2013 18:50:25 -0800
+Subject: timekeeping: Fix lost updates to tai adjustment
+
+From: John Stultz <john.stultz@linaro.org>
+
+commit f55c07607a38f84b5c7e6066ee1cfe433fa5643c upstream.
+
+Since 48cdc135d4840 (Implement a shadow timekeeper), we have to
+call timekeeping_update() after any adjustment to the timekeeping
+structure in order to make sure that any adjustments to the structure
+persist.
+
+Unfortunately, the updates to the tai offset via adjtimex do not
+trigger this update, causing adjustments to the tai offset to be
+made and then over-written by the previous value at the next
+update_wall_time() call.
+
+This patch resovles the issue by calling timekeeping_update()
+right after setting the tai offset.
+
+Cc: Sasha Levin <sasha.levin@oracle.com>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: Prarit Bhargava <prarit@redhat.com>
+Cc: Richard Cochran <richardcochran@gmail.com>
+Cc: Ingo Molnar <mingo@kernel.org>
+Signed-off-by: John Stultz <john.stultz@linaro.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/time/timekeeping.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/kernel/time/timekeeping.c
++++ b/kernel/time/timekeeping.c
+@@ -610,6 +610,7 @@ void timekeeping_set_tai_offset(s32 tai_
+ raw_spin_lock_irqsave(&timekeeper_lock, flags);
+ write_seqcount_begin(&timekeeper_seq);
+ __timekeeping_set_tai_offset(tk, tai_offset);
++ timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
+ write_seqcount_end(&timekeeper_seq);
+ raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
+ clock_was_set();
+@@ -1698,7 +1699,7 @@ int do_adjtimex(struct timex *txc)
+
+ if (tai != orig_tai) {
+ __timekeeping_set_tai_offset(tk, tai);
+- update_pvclock_gtod(tk, true);
++ timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
+ clock_was_set_delayed();
+ }
+ write_seqcount_end(&timekeeper_seq);
--- /dev/null
+From 5258d3f25c76f6ab86e9333abf97a55a877d3870 Mon Sep 17 00:00:00 2001
+From: John Stultz <john.stultz@linaro.org>
+Date: Wed, 11 Dec 2013 20:07:49 -0800
+Subject: timekeeping: Fix potential lost pv notification of time change
+
+From: John Stultz <john.stultz@linaro.org>
+
+commit 5258d3f25c76f6ab86e9333abf97a55a877d3870 upstream.
+
+In 780427f0e11 (Indicate that clock was set in the pvclock
+gtod notifier), logic was added to pass a CLOCK_WAS_SET
+notification to the pvclock notifier chain.
+
+While that patch added a action flag returned from
+accumulate_nsecs_to_secs(), it only uses the returned value
+in one location, and not in the logarithmic accumulation.
+
+This means if a leap second triggered during the logarithmic
+accumulation (which is most likely where it would happen),
+the notification that the clock was set would not make it to
+the pv notifiers.
+
+This patch extends the logarithmic_accumulation pass down
+that action flag so proper notification will occur.
+
+This patch also changes the varialbe action -> clock_set
+per Ingo's suggestion.
+
+Cc: Sasha Levin <sasha.levin@oracle.com>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: Ingo Molnar <mingo@kernel.org>
+Cc: David Vrabel <david.vrabel@citrix.com>
+Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+Cc: Prarit Bhargava <prarit@redhat.com>
+Cc: Richard Cochran <richardcochran@gmail.com>
+Cc: <xen-devel@lists.xen.org>
+Signed-off-by: John Stultz <john.stultz@linaro.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/time/timekeeping.c | 20 +++++++++++---------
+ 1 file changed, 11 insertions(+), 9 deletions(-)
+
+--- a/kernel/time/timekeeping.c
++++ b/kernel/time/timekeeping.c
+@@ -1256,7 +1256,7 @@ out_adjust:
+ static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk)
+ {
+ u64 nsecps = (u64)NSEC_PER_SEC << tk->shift;
+- unsigned int action = 0;
++ unsigned int clock_set = 0;
+
+ while (tk->xtime_nsec >= nsecps) {
+ int leap;
+@@ -1279,10 +1279,10 @@ static inline unsigned int accumulate_ns
+ __timekeeping_set_tai_offset(tk, tk->tai_offset - leap);
+
+ clock_was_set_delayed();
+- action = TK_CLOCK_WAS_SET;
++ clock_set = TK_CLOCK_WAS_SET;
+ }
+ }
+- return action;
++ return clock_set;
+ }
+
+ /**
+@@ -1295,7 +1295,8 @@ static inline unsigned int accumulate_ns
+ * Returns the unconsumed cycles.
+ */
+ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
+- u32 shift)
++ u32 shift,
++ unsigned int *clock_set)
+ {
+ cycle_t interval = tk->cycle_interval << shift;
+ u64 raw_nsecs;
+@@ -1309,7 +1310,7 @@ static cycle_t logarithmic_accumulation(
+ tk->cycle_last += interval;
+
+ tk->xtime_nsec += tk->xtime_interval << shift;
+- accumulate_nsecs_to_secs(tk);
++ *clock_set |= accumulate_nsecs_to_secs(tk);
+
+ /* Accumulate raw time */
+ raw_nsecs = (u64)tk->raw_interval << shift;
+@@ -1367,7 +1368,7 @@ static void update_wall_time(void)
+ struct timekeeper *tk = &shadow_timekeeper;
+ cycle_t offset;
+ int shift = 0, maxshift;
+- unsigned int action;
++ unsigned int clock_set = 0;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&timekeeper_lock, flags);
+@@ -1402,7 +1403,8 @@ static void update_wall_time(void)
+ maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
+ shift = min(shift, maxshift);
+ while (offset >= tk->cycle_interval) {
+- offset = logarithmic_accumulation(tk, offset, shift);
++ offset = logarithmic_accumulation(tk, offset, shift,
++ &clock_set);
+ if (offset < tk->cycle_interval<<shift)
+ shift--;
+ }
+@@ -1420,7 +1422,7 @@ static void update_wall_time(void)
+ * Finally, make sure that after the rounding
+ * xtime_nsec isn't larger than NSEC_PER_SEC
+ */
+- action = accumulate_nsecs_to_secs(tk);
++ clock_set |= accumulate_nsecs_to_secs(tk);
+
+ write_seqcount_begin(&timekeeper_seq);
+ /* Update clock->cycle_last with the new value */
+@@ -1436,7 +1438,7 @@ static void update_wall_time(void)
+ * updating.
+ */
+ memcpy(real_tk, tk, sizeof(*tk));
+- timekeeping_update(real_tk, action);
++ timekeeping_update(real_tk, clock_set);
+ write_seqcount_end(&timekeeper_seq);
+ out:
+ raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
projects / thirdparty / kernel / stable-queue.git / commitdiff
