Merge 4.4.257 into android-4.4-p

Changes in 4.4.257
	net_sched: reject silly cell_log in qdisc_get_rtab()
	futex,rt_mutex: Provide futex specific rt_mutex API
	futex: Remove rt_mutex_deadlock_account_*()
	futex: Rework inconsistent rt_mutex/futex_q state
	futex: Avoid violating the 10th rule of futex
	futex: Replace pointless printk in fixup_owner()
	futex: Provide and use pi_state_update_owner()
	rtmutex: Remove unused argument from rt_mutex_proxy_unlock()
	futex: Use pi_state_update_owner() in put_pi_state()
	futex: Simplify fixup_pi_state_owner()
	futex: Handle faults correctly for PI futexes
	usb: udc: core: Use lock when write to soft_connect
	scsi: libfc: Avoid invoking response handler twice if ep is already completed
	scsi: ibmvfc: Set default timeout to avoid crash during migration
	stable: clamp SUBLEVEL in 4.4 and 4.9
	USB: serial: cp210x: add pid/vid for WSDA-200-USB
	USB: serial: cp210x: add new VID/PID for supporting Teraoka AD2000
	USB: serial: option: Adding support for Cinterion MV31
	Input: i8042 - unbreak Pegatron C15B
	net: lapb: Copy the skb before sending a packet
	ELF/MIPS build fix
	elfcore: fix building with clang
	USB: gadget: legacy: fix an error code in eth_bind()
	USB: usblp: don't call usb_set_interface if there's a single alt
	usb: dwc2: Fix endpoint direction check in ep_from_windex
	mac80211: fix station rate table updates on assoc
	kretprobe: Avoid re-registration of the same kretprobe earlier
	cifs: report error instead of invalid when revalidating a dentry fails
	mmc: core: Limit retries when analyse of SDIO tuples fails
	ARM: footbridge: fix dc21285 PCI configuration accessors
	mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page
	mm: hugetlb: fix a race between isolating and freeing page
	mm: hugetlb: remove VM_BUG_ON_PAGE from page_huge_active
	x86/build: Disable CET instrumentation in the kernel
	x86/apic: Add extra serialization for non-serializing MSRs
	Input: xpad - sync supported devices with fork on GitHub
	ACPI: thermal: Do not call acpi_thermal_check() directly
	ALSA: hda/realtek - Fix typo of pincfg for Dell quirk
	Linux 4.4.257

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I3bd45d2e19a068d1d25e2d57f9d171a0b57061ad

1 files changed, 77 insertions, 50 deletions

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index dd173df9ee5e..1c0cb5c3c6ad 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -937,8 +937,6 @@ takeit:
 	 */
 	rt_mutex_set_owner(lock, task);
 
-	rt_mutex_deadlock_account_lock(lock, task);
-
 	return 1;
 }
 
@@ -1286,6 +1284,19 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
 	return ret;
 }
 
+static inline int __rt_mutex_slowtrylock(struct rt_mutex *lock)
+{
+	int ret = try_to_take_rt_mutex(lock, current, NULL);
+
+	/*
+	 * try_to_take_rt_mutex() sets the lock waiters bit
+	 * unconditionally. Clean this up.
+	 */
+	fixup_rt_mutex_waiters(lock);
+
+	return ret;
+}
+
 /*
  * Slow path try-lock function:
  */
@@ -1307,13 +1318,7 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
 	 */
 	raw_spin_lock(&lock->wait_lock);
 
-	ret = try_to_take_rt_mutex(lock, current, NULL);
-
-	/*
-	 * try_to_take_rt_mutex() sets the lock waiters bit
-	 * unconditionally. Clean this up.
-	 */
-	fixup_rt_mutex_waiters(lock);
+	ret = __rt_mutex_slowtrylock(lock);
 
 	raw_spin_unlock(&lock->wait_lock);
 
@@ -1331,8 +1336,6 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
 
 	debug_rt_mutex_unlock(lock);
 
-	rt_mutex_deadlock_account_unlock(current);
-
 	/*
 	 * We must be careful here if the fast path is enabled. If we
 	 * have no waiters queued we cannot set owner to NULL here
@@ -1398,11 +1401,10 @@ rt_mutex_fastlock(struct rt_mutex *lock, int state,
 				struct hrtimer_sleeper *timeout,
 				enum rtmutex_chainwalk chwalk))
 {
-	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-		rt_mutex_deadlock_account_lock(lock, current);
+	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
 		return 0;
-	} else
-		return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
+
+	return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
 }
 
 static inline int
@@ -1414,21 +1416,19 @@ rt_mutex_timed_fastlock(struct rt_mutex *lock, int state,
 				      enum rtmutex_chainwalk chwalk))
 {
 	if (chwalk == RT_MUTEX_MIN_CHAINWALK &&
-	    likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-		rt_mutex_deadlock_account_lock(lock, current);
+	    likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
 		return 0;
-	} else
-		return slowfn(lock, state, timeout, chwalk);
+
+	return slowfn(lock, state, timeout, chwalk);
 }
 
 static inline int
 rt_mutex_fasttrylock(struct rt_mutex *lock,
 		     int (*slowfn)(struct rt_mutex *lock))
 {
-	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) {
-		rt_mutex_deadlock_account_lock(lock, current);
+	if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
 		return 1;
-	}
+
 	return slowfn(lock);
 }
 
@@ -1438,19 +1438,18 @@ rt_mutex_fastunlock(struct rt_mutex *lock,
 				   struct wake_q_head *wqh))
 {
 	WAKE_Q(wake_q);
+	bool deboost;
 
-	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
-		rt_mutex_deadlock_account_unlock(current);
+	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+		return;
 
-	} else {
-		bool deboost = slowfn(lock, &wake_q);
+	deboost = slowfn(lock, &wake_q);
 
-		wake_up_q(&wake_q);
+	wake_up_q(&wake_q);
 
-		/* Undo pi boosting if necessary: */
-		if (deboost)
-			rt_mutex_adjust_prio(current);
-	}
+	/* Undo pi boosting if necessary: */
+	if (deboost)
+		rt_mutex_adjust_prio(current);
 }
 
 /**
@@ -1485,15 +1484,28 @@ EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
 
 /*
  * Futex variant with full deadlock detection.
+ * Futex variants must not use the fast-path, see __rt_mutex_futex_unlock().
  */
-int rt_mutex_timed_futex_lock(struct rt_mutex *lock,
+int __sched rt_mutex_timed_futex_lock(struct rt_mutex *lock,
 			      struct hrtimer_sleeper *timeout)
 {
 	might_sleep();
 
-	return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout,
-				       RT_MUTEX_FULL_CHAINWALK,
-				       rt_mutex_slowlock);
+	return rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE,
+				 timeout, RT_MUTEX_FULL_CHAINWALK);
+}
+
+/*
+ * Futex variant, must not use fastpath.
+ */
+int __sched rt_mutex_futex_trylock(struct rt_mutex *lock)
+{
+	return rt_mutex_slowtrylock(lock);
+}
+
+int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
+{
+	return __rt_mutex_slowtrylock(lock);
 }
 
 /**
@@ -1552,20 +1564,38 @@ void __sched rt_mutex_unlock(struct rt_mutex *lock)
 EXPORT_SYMBOL_GPL(rt_mutex_unlock);
 
 /**
- * rt_mutex_futex_unlock - Futex variant of rt_mutex_unlock
- * @lock: the rt_mutex to be unlocked
- *
- * Returns: true/false indicating whether priority adjustment is
- * required or not.
+ * Futex variant, that since futex variants do not use the fast-path, can be
+ * simple and will not need to retry.
  */
-bool __sched rt_mutex_futex_unlock(struct rt_mutex *lock,
-				   struct wake_q_head *wqh)
+bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
+				    struct wake_q_head *wake_q)
 {
-	if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) {
-		rt_mutex_deadlock_account_unlock(current);
-		return false;
+	lockdep_assert_held(&lock->wait_lock);
+
+	debug_rt_mutex_unlock(lock);
+
+	if (!rt_mutex_has_waiters(lock)) {
+		lock->owner = NULL;
+		return false; /* done */
+	}
+
+	mark_wakeup_next_waiter(wake_q, lock);
+	return true; /* deboost and wakeups */
+}
+
+void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
+{
+	WAKE_Q(wake_q);
+	bool deboost;
+
+	raw_spin_lock_irq(&lock->wait_lock);
+	deboost = __rt_mutex_futex_unlock(lock, &wake_q);
+	raw_spin_unlock_irq(&lock->wait_lock);
+
+	if (deboost) {
+		wake_up_q(&wake_q);
+		rt_mutex_adjust_prio(current);
 	}
-	return rt_mutex_slowunlock(lock, wqh);
 }
 
 /**
@@ -1622,7 +1652,6 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
 	__rt_mutex_init(lock, NULL);
 	debug_rt_mutex_proxy_lock(lock, proxy_owner);
 	rt_mutex_set_owner(lock, proxy_owner);
-	rt_mutex_deadlock_account_lock(lock, proxy_owner);
 }
 
 /**
@@ -1633,12 +1662,10 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
  * No locking. Caller has to do serializing itself
  * Special API call for PI-futex support
  */
-void rt_mutex_proxy_unlock(struct rt_mutex *lock,
-			   struct task_struct *proxy_owner)
+void rt_mutex_proxy_unlock(struct rt_mutex *lock)
 {
 	debug_rt_mutex_proxy_unlock(lock);
 	rt_mutex_set_owner(lock, NULL);
-	rt_mutex_deadlock_account_unlock(proxy_owner);
 }
 
 /**