1 files changed, 28 insertions, 18 deletions

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index b7efd3c1a882..9c4069151955 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -248,6 +248,9 @@ struct smi_info {
 	/* The timer for this si. */
 	struct timer_list   si_timer;
 
+	/* This flag is set, if the timer is running (timer_pending() isn't enough) */
+	bool		    timer_running;
+
 	/* The time (in jiffies) the last timeout occurred at. */
 	unsigned long       last_timeout_jiffies;
 
@@ -434,6 +437,13 @@ static void start_clear_flags(struct smi_info *smi_info)
 	smi_info->si_state = SI_CLEARING_FLAGS;
 }
 
+static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val)
+{
+	smi_info->last_timeout_jiffies = jiffies;
+	mod_timer(&smi_info->si_timer, new_val);
+	smi_info->timer_running = true;
+}
+
 /*
  * When we have a situtaion where we run out of memory and cannot
  * allocate messages, we just leave them in the BMC and run the system
@@ -446,8 +456,7 @@ static inline void disable_si_irq(struct smi_info *smi_info)
 		start_disable_irq(smi_info);
 		smi_info->interrupt_disabled = 1;
 		if (!atomic_read(&smi_info->stop_operation))
-			mod_timer(&smi_info->si_timer,
-				  jiffies + SI_TIMEOUT_JIFFIES);
+			smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
 	}
 }
 
@@ -907,15 +916,7 @@ static void sender(void                *send_info,
 		list_add_tail(&msg->link, &smi_info->xmit_msgs);
 
 	if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) {
-		/*
-		 * last_timeout_jiffies is updated here to avoid
-		 * smi_timeout() handler passing very large time_diff
-		 * value to smi_event_handler() that causes
-		 * the send command to abort.
-		 */
-		smi_info->last_timeout_jiffies = jiffies;
-
-		mod_timer(&smi_info->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
+		smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
 
 		if (smi_info->thread)
 			wake_up_process(smi_info->thread);
@@ -1004,6 +1005,17 @@ static int ipmi_thread(void *data)
 
 		spin_lock_irqsave(&(smi_info->si_lock), flags);
 		smi_result = smi_event_handler(smi_info, 0);
+
+		/*
+		 * If the driver is doing something, there is a possible
+		 * race with the timer.  If the timer handler see idle,
+		 * and the thread here sees something else, the timer
+		 * handler won't restart the timer even though it is
+		 * required.  So start it here if necessary.
+		 */
+		if (smi_result != SI_SM_IDLE && !smi_info->timer_running)
+			smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES);
+
 		spin_unlock_irqrestore(&(smi_info->si_lock), flags);
 		busy_wait = ipmi_thread_busy_wait(smi_result, smi_info,
 						  &busy_until);
@@ -1073,10 +1085,6 @@ static void smi_timeout(unsigned long data)
 		     * SI_USEC_PER_JIFFY);
 	smi_result = smi_event_handler(smi_info, time_diff);
 
-	spin_unlock_irqrestore(&(smi_info->si_lock), flags);
-
-	smi_info->last_timeout_jiffies = jiffies_now;
-
 	if ((smi_info->irq) && (!smi_info->interrupt_disabled)) {
 		/* Running with interrupts, only do long timeouts. */
 		timeout = jiffies + SI_TIMEOUT_JIFFIES;
@@ -1098,7 +1106,10 @@ static void smi_timeout(unsigned long data)
 
  do_mod_timer:
 	if (smi_result != SI_SM_IDLE)
-		mod_timer(&(smi_info->si_timer), timeout);
+		smi_mod_timer(smi_info, timeout);
+	else
+		smi_info->timer_running = false;
+	spin_unlock_irqrestore(&(smi_info->si_lock), flags);
 }
 
 static irqreturn_t si_irq_handler(int irq, void *data)
@@ -1146,8 +1157,7 @@ static int smi_start_processing(void       *send_info,
 
 	/* Set up the timer that drives the interface. */
 	setup_timer(&new_smi->si_timer, smi_timeout, (long)new_smi);
-	new_smi->last_timeout_jiffies = jiffies;
-	mod_timer(&new_smi->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
+	smi_mod_timer(new_smi, jiffies + SI_TIMEOUT_JIFFIES);
 
 	/*
 	 * Check if the user forcefully enabled the daemon.