usb_storage: don't use set_freezable_with_signal()

index c325e69..aa84b3d 100644
@@ -831,7 +831,8 @@ static int usb_stor_scan_thread(void * __us)
 
 	dev_dbg(dev, "device found\n");
 
-	set_freezable_with_signal();
+	set_freezable();
+
 	/*
 	 * Wait for the timeout to expire or for a disconnect
 	 *

@@ -839,16 +840,16 @@ static int usb_stor_scan_thread(void * __us)
 	 * fail to freeze, but we can't be non-freezable either. Nor can
 	 * khubd freeze while waiting for scanning to complete as it may
 	 * hold the device lock, causing a hang when suspending devices.
-	 * So we request a fake signal when freezing and use
-	 * interruptible sleep to kick us out of our wait early when
-	 * freezing happens.
+	 * So instead of using wait_event_freezable(), explicitly test
+	 * for (DONT_SCAN || freezing) in interruptible wait and proceed
+	 * if any of DONT_SCAN, freezing or timeout has happened.
 	 */
 	if (delay_use > 0) {
 		dev_dbg(dev, "waiting for device to settle "
 				"before scanning\n");
 		wait_event_interruptible_timeout(us->delay_wait,
-				test_bit(US_FLIDX_DONT_SCAN, &us->dflags),
-				delay_use * HZ);
+				test_bit(US_FLIDX_DONT_SCAN, &us->dflags) ||
+				freezing(current), delay_use * HZ);
 	}
 
 	/* If the device is still connected, perform the scanning */

index 4b3dc4c..5f32321 100644
@@ -49,7 +49,7 @@ static inline bool try_to_freeze(void)
 }
 
 extern bool freeze_task(struct task_struct *p);
-extern bool __set_freezable(bool with_signal);
+extern bool set_freezable(void);
 
 #ifdef CONFIG_CGROUP_FREEZER
 extern bool cgroup_freezing(struct task_struct *task);

@@ -105,23 +105,6 @@ static inline int freezer_should_skip(struct task_struct *p)
 }
 
 /*
- * Tell the freezer that the current task should be frozen by it
- */
-static inline bool set_freezable(void)
-{
-	return __set_freezable(false);
-}
-
-/*
- * Tell the freezer that the current task should be frozen by it and that it
- * should send a fake signal to the task to freeze it.
- */
-static inline bool set_freezable_with_signal(void)
-{
-	return __set_freezable(true);
-}
-
-/*
  * Freezer-friendly wrappers around wait_event_interruptible(),
  * wait_event_killable() and wait_event_interruptible_timeout(), originally
  * defined in <linux/wait.h>

@@ -181,7 +164,6 @@ static inline void freezer_do_not_count(void) {}
 static inline void freezer_count(void) {}
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
-static inline void set_freezable_with_signal(void) {}
 
 #define wait_event_freezable(wq, condition)				\
 		wait_event_interruptible(wq, condition)

index 57f916d..84fd546 100644
@@ -1781,7 +1781,6 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *
 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
-#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
 
 /*
  * Only the _current_ task can read/write to tsk->flags, but other

index 0845321..128c5aa 100644
@@ -39,7 +39,7 @@ bool freezing_slow_path(struct task_struct *p)
 	if (pm_nosig_freezing || cgroup_freezing(p))
 		return true;
 
-	if (pm_freezing && !(p->flags & PF_FREEZER_NOSIG))
+	if (pm_freezing && !(p->flags & PF_KTHREAD))
 		return true;
 
 	return false;

@@ -72,10 +72,6 @@ bool __refrigerator(bool check_kthr_stop)
 		schedule();
 	}
 
-	spin_lock_irq(&current->sighand->siglock);
-	recalc_sigpending(); /* We sent fake signal, clean it up */
-	spin_unlock_irq(&current->sighand->siglock);
-
 	pr_debug("%s left refrigerator\n", current->comm);
 
 	/*

@@ -120,7 +116,7 @@ bool freeze_task(struct task_struct *p)
 		return false;
 	}
 
-	if (!(p->flags & PF_FREEZER_NOSIG)) {
+	if (!(p->flags & PF_KTHREAD)) {
 		fake_signal_wake_up(p);
 		/*
 		 * fake_signal_wake_up() goes through p's scheduler

@@ -145,28 +141,19 @@ void __thaw_task(struct task_struct *p)
 	 * be visible to @p as waking up implies wmb.  Waking up inside
 	 * freezer_lock also prevents wakeups from leaking outside
 	 * refrigerator.
-	 *
-	 * If !FROZEN, @p hasn't reached refrigerator, recalc sigpending to
-	 * avoid leaving dangling TIF_SIGPENDING behind.
 	 */
 	spin_lock_irqsave(&freezer_lock, flags);
-	if (frozen(p)) {
+	if (frozen(p))
 		wake_up_process(p);
-	} else {
-		spin_lock(&p->sighand->siglock);
-		recalc_sigpending_and_wake(p);
-		spin_unlock(&p->sighand->siglock);
-	}
 	spin_unlock_irqrestore(&freezer_lock, flags);
 }
 
 /**
- * __set_freezable - make %current freezable
- * @with_signal: do we want %TIF_SIGPENDING for notification too?
+ * set_freezable - make %current freezable
  *
  * Mark %current freezable and enter refrigerator if necessary.
  */
-bool __set_freezable(bool with_signal)
+bool set_freezable(void)
 {
 	might_sleep();
 

@@ -177,10 +164,8 @@ bool __set_freezable(bool with_signal)
 	 */
 	spin_lock_irq(&freezer_lock);
 	current->flags &= ~PF_NOFREEZE;
-	if (with_signal)
-		current->flags &= ~PF_FREEZER_NOSIG;
 	spin_unlock_irq(&freezer_lock);
 
 	return try_to_freeze();
 }
-EXPORT_SYMBOL(__set_freezable);
+EXPORT_SYMBOL(set_freezable);

index a6cbeea..7a4c862 100644
@@ -282,7 +282,7 @@ int kthreadd(void *unused)
 	set_cpus_allowed_ptr(tsk, cpu_all_mask);
 	set_mems_allowed(node_states[N_HIGH_MEMORY]);
 
-	current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;
+	current->flags |= PF_NOFREEZE;
 
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);