2 files changed, 32 insertions, 6 deletions

diff --git a/sys/ofed/drivers/infiniband/core/ib_sysfs.c b/sys/ofed/drivers/infiniband/core/ib_sysfs.c
index c393bb64a034..806f4aba6c76 100644
--- a/sys/ofed/drivers/infiniband/core/ib_sysfs.c
+++ b/sys/ofed/drivers/infiniband/core/ib_sysfs.c
@@ -827,10 +827,15 @@ static ssize_t show_hw_stats(struct kobject *kobj, struct attribute *attr,
 		dev = port->ibdev;
 		stats = port->hw_stats;
 	}
+	mutex_lock(&stats->lock);
 	ret = update_hw_stats(dev, stats, hsa->port_num, hsa->index);
 	if (ret)
-		return ret;
-	return print_hw_stat(stats, hsa->index, buf);
+		goto unlock;
+	ret = print_hw_stat(stats, hsa->index, buf);
+unlock:
+	mutex_unlock(&stats->lock);
+
+	return ret;
 }
 
 static ssize_t show_stats_lifespan(struct kobject *kobj,
@@ -838,17 +843,25 @@ static ssize_t show_stats_lifespan(struct kobject *kobj,
 				   char *buf)
 {
 	struct hw_stats_attribute *hsa;
+	struct rdma_hw_stats *stats;
 	int msecs;
 
 	hsa = container_of(attr, struct hw_stats_attribute, attr);
 	if (!hsa->port_num) {
 		struct ib_device *dev = container_of((struct device *)kobj,
 						     struct ib_device, dev);
-		msecs = jiffies_to_msecs(dev->hw_stats->lifespan);
+
+		stats = dev->hw_stats;
 	} else {
 		struct ib_port *p = container_of(kobj, struct ib_port, kobj);
-		msecs = jiffies_to_msecs(p->hw_stats->lifespan);
+
+		stats = p->hw_stats;
 	}
+
+	mutex_lock(&stats->lock);
+	msecs = jiffies_to_msecs(stats->lifespan);
+	mutex_unlock(&stats->lock);
+
 	return sprintf(buf, "%d\n", msecs);
 }
 
@@ -857,6 +870,7 @@ static ssize_t set_stats_lifespan(struct kobject *kobj,
 				  const char *buf, size_t count)
 {
 	struct hw_stats_attribute *hsa;
+	struct rdma_hw_stats *stats;
 	int msecs;
 	int jiffies;
 	int ret;
@@ -871,11 +885,18 @@ static ssize_t set_stats_lifespan(struct kobject *kobj,
 	if (!hsa->port_num) {
 		struct ib_device *dev = container_of((struct device *)kobj,
 						     struct ib_device, dev);
-		dev->hw_stats->lifespan = jiffies;
+
+		stats = dev->hw_stats;
 	} else {
 		struct ib_port *p = container_of(kobj, struct ib_port, kobj);
-		p->hw_stats->lifespan = jiffies;
+
+		stats = p->hw_stats;
 	}
+
+	mutex_lock(&stats->lock);
+	stats->lifespan = jiffies;
+	mutex_unlock(&stats->lock);
+
 	return count;
 }
 
@@ -968,6 +989,7 @@ static void setup_hw_stats(struct ib_device *device, struct ib_port *port,
 		sysfs_attr_init(hsag->attrs[i]);
 	}
 
+	mutex_init(&stats->lock);
 	/* treat an error here as non-fatal */
 	hsag->attrs[i] = alloc_hsa_lifespan("lifespan", port_num);
 	if (hsag->attrs[i])
diff --git a/sys/ofed/include/rdma/ib_verbs.h b/sys/ofed/include/rdma/ib_verbs.h
index 2399a3a53120..b18aa2855166 100644
--- a/sys/ofed/include/rdma/ib_verbs.h
+++ b/sys/ofed/include/rdma/ib_verbs.h
@@ -438,6 +438,9 @@ enum ib_port_speed {
 
 /**
  * struct rdma_hw_stats
+ * @lock - Mutex to protect parallel write access to lifespan and values
+ *    of counters, which are 64bits and not guaranteeed to be written
+ *    atomicaly on 32bits systems.
  * @timestamp - Used by the core code to track when the last update was
  * @lifespan - Used by the core code to determine how old the counters
  *   should be before being updated again.  Stored in jiffies, defaults
@@ -453,6 +456,7 @@ enum ib_port_speed {
  *   filled in by the drivers get_stats routine
  */
 struct rdma_hw_stats {
+	struct mutex	lock; /* Protect lifespan and values[] */
 	unsigned long	timestamp;
 	unsigned long	lifespan;
 	const char * const *names;