diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index a74ce885b54125b3852cd9f7de66ec5ee2a52ea3..c518659b4d9fe17a39edc9a53651198c08aa2b5f 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -32,6 +32,7 @@
 #include <linux/moduleparam.h>
 #include <linux/workqueue.h>
 #include <linux/uuid.h>
+#include <linux/nospec.h>
 
 #define IPMI_DRIVER_VERSION "39.2"
 
@@ -62,7 +63,8 @@ static void ipmi_debug_msg(const char *title, unsigned char *data,
 { }
 #endif
 
-static int initialized;
+static bool initialized;
+static bool drvregistered;
 
 enum ipmi_panic_event_op {
 	IPMI_SEND_PANIC_EVENT_NONE,
@@ -612,7 +614,7 @@ static DEFINE_MUTEX(ipmidriver_mutex);
 
 static LIST_HEAD(ipmi_interfaces);
 static DEFINE_MUTEX(ipmi_interfaces_mutex);
-DEFINE_STATIC_SRCU(ipmi_interfaces_srcu);
+struct srcu_struct ipmi_interfaces_srcu;
 
 /*
  * List of watchers that want to know when smi's are added and deleted.
@@ -720,7 +722,15 @@ struct watcher_entry {
 int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
 {
 	struct ipmi_smi *intf;
-	int index;
+	int index, rv;
+
+	/*
+	 * Make sure the driver is actually initialized, this handles
+	 * problems with initialization order.
+	 */
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
 
 	mutex_lock(&smi_watchers_mutex);
 
@@ -884,7 +894,7 @@ static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
 
 		if (user) {
 			user->handler->ipmi_recv_hndl(msg, user->handler_data);
-			release_ipmi_user(msg->user, index);
+			release_ipmi_user(user, index);
 		} else {
 			/* User went away, give up. */
 			ipmi_free_recv_msg(msg);
@@ -1076,7 +1086,7 @@ int ipmi_create_user(unsigned int          if_num,
 {
 	unsigned long flags;
 	struct ipmi_user *new_user;
-	int           rv = 0, index;
+	int           rv, index;
 	struct ipmi_smi *intf;
 
 	/*
@@ -1094,18 +1104,9 @@ int ipmi_create_user(unsigned int          if_num,
 	 * Make sure the driver is actually initialized, this handles
 	 * problems with initialization order.
 	 */
-	if (!initialized) {
-		rv = ipmi_init_msghandler();
-		if (rv)
-			return rv;
-
-		/*
-		 * The init code doesn't return an error if it was turned
-		 * off, but it won't initialize.  Check that.
-		 */
-		if (!initialized)
-			return -ENODEV;
-	}
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
 
 	new_user = kmalloc(sizeof(*new_user), GFP_KERNEL);
 	if (!new_user)
@@ -1183,6 +1184,7 @@ EXPORT_SYMBOL(ipmi_get_smi_info);
 static void free_user(struct kref *ref)
 {
 	struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount);
+	cleanup_srcu_struct(&user->release_barrier);
 	kfree(user);
 }
 
@@ -1259,7 +1261,6 @@ int ipmi_destroy_user(struct ipmi_user *user)
 {
 	_ipmi_destroy_user(user);
 
-	cleanup_srcu_struct(&user->release_barrier);
 	kref_put(&user->refcount, free_user);
 
 	return 0;
@@ -1298,10 +1299,12 @@ int ipmi_set_my_address(struct ipmi_user *user,
 	if (!user)
 		return -ENODEV;
 
-	if (channel >= IPMI_MAX_CHANNELS)
+	if (channel >= IPMI_MAX_CHANNELS) {
 		rv = -EINVAL;
-	else
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
 		user->intf->addrinfo[channel].address = address;
+	}
 	release_ipmi_user(user, index);
 
 	return rv;
@@ -1318,10 +1321,12 @@ int ipmi_get_my_address(struct ipmi_user *user,
 	if (!user)
 		return -ENODEV;
 
-	if (channel >= IPMI_MAX_CHANNELS)
+	if (channel >= IPMI_MAX_CHANNELS) {
 		rv = -EINVAL;
-	else
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
 		*address = user->intf->addrinfo[channel].address;
+	}
 	release_ipmi_user(user, index);
 
 	return rv;
@@ -1338,10 +1343,12 @@ int ipmi_set_my_LUN(struct ipmi_user *user,
 	if (!user)
 		return -ENODEV;
 
-	if (channel >= IPMI_MAX_CHANNELS)
+	if (channel >= IPMI_MAX_CHANNELS) {
 		rv = -EINVAL;
-	else
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
 		user->intf->addrinfo[channel].lun = LUN & 0x3;
+	}
 	release_ipmi_user(user, index);
 
 	return rv;
@@ -1358,10 +1365,12 @@ int ipmi_get_my_LUN(struct ipmi_user *user,
 	if (!user)
 		return -ENODEV;
 
-	if (channel >= IPMI_MAX_CHANNELS)
+	if (channel >= IPMI_MAX_CHANNELS) {
 		rv = -EINVAL;
-	else
+	} else {
+		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
 		*address = user->intf->addrinfo[channel].lun;
+	}
 	release_ipmi_user(user, index);
 
 	return rv;
@@ -2184,6 +2193,7 @@ static int check_addr(struct ipmi_smi  *intf,
 {
 	if (addr->channel >= IPMI_MAX_CHANNELS)
 		return -EINVAL;
+	addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS);
 	*lun = intf->addrinfo[addr->channel].lun;
 	*saddr = intf->addrinfo[addr->channel].address;
 	return 0;
@@ -3291,17 +3301,9 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
 	 * Make sure the driver is actually initialized, this handles
 	 * problems with initialization order.
 	 */
-	if (!initialized) {
-		rv = ipmi_init_msghandler();
-		if (rv)
-			return rv;
-		/*
-		 * The init code doesn't return an error if it was turned
-		 * off, but it won't initialize.  Check that.
-		 */
-		if (!initialized)
-			return -ENODEV;
-	}
+	rv = ipmi_init_msghandler();
+	if (rv)
+		return rv;
 
 	intf = kzalloc(sizeof(*intf), GFP_KERNEL);
 	if (!intf)
@@ -5017,6 +5019,22 @@ static int panic_event(struct notifier_block *this,
 	return NOTIFY_DONE;
 }
 
+/* Must be called with ipmi_interfaces_mutex held. */
+static int ipmi_register_driver(void)
+{
+	int rv;
+
+	if (drvregistered)
+		return 0;
+
+	rv = driver_register(&ipmidriver.driver);
+	if (rv)
+		pr_err("Could not register IPMI driver\n");
+	else
+		drvregistered = true;
+	return rv;
+}
+
 static struct notifier_block panic_block = {
 	.notifier_call	= panic_event,
 	.next		= NULL,
@@ -5027,66 +5045,75 @@ static int ipmi_init_msghandler(void)
 {
 	int rv;
 
+	mutex_lock(&ipmi_interfaces_mutex);
+	rv = ipmi_register_driver();
+	if (rv)
+		goto out;
 	if (initialized)
-		return 0;
-
-	rv = driver_register(&ipmidriver.driver);
-	if (rv) {
-		pr_err("Could not register IPMI driver\n");
-		return rv;
-	}
+		goto out;
 
-	pr_info("version " IPMI_DRIVER_VERSION "\n");
+	init_srcu_struct(&ipmi_interfaces_srcu);
 
 	timer_setup(&ipmi_timer, ipmi_timeout, 0);
 	mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
 
 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
 
-	initialized = 1;
+	initialized = true;
 
-	return 0;
+out:
+	mutex_unlock(&ipmi_interfaces_mutex);
+	return rv;
 }
 
 static int __init ipmi_init_msghandler_mod(void)
 {
-	ipmi_init_msghandler();
-	return 0;
+	int rv;
+
+	pr_info("version " IPMI_DRIVER_VERSION "\n");
+
+	mutex_lock(&ipmi_interfaces_mutex);
+	rv = ipmi_register_driver();
+	mutex_unlock(&ipmi_interfaces_mutex);
+
+	return rv;
 }
 
 static void __exit cleanup_ipmi(void)
 {
 	int count;
 
-	if (!initialized)
-		return;
-
-	atomic_notifier_chain_unregister(&panic_notifier_list, &panic_block);
+	if (initialized) {
+		atomic_notifier_chain_unregister(&panic_notifier_list,
+						 &panic_block);
 
-	/*
-	 * This can't be called if any interfaces exist, so no worry
-	 * about shutting down the interfaces.
-	 */
+		/*
+		 * This can't be called if any interfaces exist, so no worry
+		 * about shutting down the interfaces.
+		 */
 
-	/*
-	 * Tell the timer to stop, then wait for it to stop.  This
-	 * avoids problems with race conditions removing the timer
-	 * here.
-	 */
-	atomic_inc(&stop_operation);
-	del_timer_sync(&ipmi_timer);
+		/*
+		 * Tell the timer to stop, then wait for it to stop.  This
+		 * avoids problems with race conditions removing the timer
+		 * here.
+		 */
+		atomic_inc(&stop_operation);
+		del_timer_sync(&ipmi_timer);
 
-	driver_unregister(&ipmidriver.driver);
+		initialized = false;
 
-	initialized = 0;
+		/* Check for buffer leaks. */
+		count = atomic_read(&smi_msg_inuse_count);
+		if (count != 0)
+			pr_warn("SMI message count %d at exit\n", count);
+		count = atomic_read(&recv_msg_inuse_count);
+		if (count != 0)
+			pr_warn("recv message count %d at exit\n", count);
 
-	/* Check for buffer leaks. */
-	count = atomic_read(&smi_msg_inuse_count);
-	if (count != 0)
-		pr_warn("SMI message count %d at exit\n", count);
-	count = atomic_read(&recv_msg_inuse_count);
-	if (count != 0)
-		pr_warn("recv message count %d at exit\n", count);
+		cleanup_srcu_struct(&ipmi_interfaces_srcu);
+	}
+	if (drvregistered)
+		driver_unregister(&ipmidriver.driver);
 }
 module_exit(cleanup_ipmi);
 
diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index ca9528c4f183e7ea57cb71805b5a09aaf3bedd69..b7a1ae2afaeac7435410f6c100d7e9941f2cb486 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -632,8 +632,9 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 
 		/* Remove the multi-part read marker. */
 		len -= 2;
+		data += 2;
 		for (i = 0; i < len; i++)
-			ssif_info->data[i] = data[i+2];
+			ssif_info->data[i] = data[i];
 		ssif_info->multi_len = len;
 		ssif_info->multi_pos = 1;
 
@@ -661,8 +662,19 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		}
 
 		blocknum = data[0];
+		len--;
+		data++;
+
+		if (blocknum != 0xff && len != 31) {
+		    /* All blocks but the last must have 31 data bytes. */
+			result = -EIO;
+			if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+				pr_info("Received middle message <31\n");
 
-		if (ssif_info->multi_len + len - 1 > IPMI_MAX_MSG_LENGTH) {
+			goto continue_op;
+		}
+
+		if (ssif_info->multi_len + len > IPMI_MAX_MSG_LENGTH) {
 			/* Received message too big, abort the operation. */
 			result = -E2BIG;
 			if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
@@ -671,16 +683,14 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 			goto continue_op;
 		}
 
-		/* Remove the blocknum from the data. */
-		len--;
 		for (i = 0; i < len; i++)
-			ssif_info->data[i + ssif_info->multi_len] = data[i + 1];
+			ssif_info->data[i + ssif_info->multi_len] = data[i];
 		ssif_info->multi_len += len;
 		if (blocknum == 0xff) {
 			/* End of read */
 			len = ssif_info->multi_len;
 			data = ssif_info->data;
-		} else if (blocknum + 1 != ssif_info->multi_pos) {
+		} else if (blocknum != ssif_info->multi_pos) {
 			/*
 			 * Out of sequence block, just abort.  Block
 			 * numbers start at zero for the second block,
@@ -707,6 +717,7 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		}
 	}
 
+ continue_op:
 	if (result < 0) {
 		ssif_inc_stat(ssif_info, receive_errors);
 	} else {
@@ -714,8 +725,6 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		ssif_inc_stat(ssif_info, received_message_parts);
 	}
 
-
- continue_op:
 	if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
 		pr_info("DONE 1: state = %d, result=%d\n",
 			ssif_info->ssif_state, result);