diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 8d6197a88b54..f8fb7589192e 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -865,8 +865,10 @@ int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
 
-	if (slots < msg_slots)
+	if ((u32)slots < msg_slots)
 		return -EMSGSIZE;
 
 	ret = mei_cl_send_disconnect(cl, cb);
@@ -1054,12 +1056,15 @@ int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
 	int rets;
 
 	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
-	slots = mei_hbuf_empty_slots(dev);
 
 	if (mei_cl_is_other_connecting(cl))
 		return 0;
 
-	if (slots < msg_slots)
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if ((u32)slots < msg_slots)
 		return -EMSGSIZE;
 
 	rets = mei_cl_send_connect(cl, cb);
@@ -1296,8 +1301,10 @@ int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
 
-	if (slots < msg_slots)
+	if ((u32)slots < msg_slots)
 		return -EMSGSIZE;
 
 	request = mei_cl_notify_fop2req(cb->fop_type);
@@ -1573,6 +1580,9 @@ int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 	}
 
 	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
+
 	len = buf->size - cb->buf_idx;
 	msg_slots = mei_data2slots(len);
 
@@ -1581,11 +1591,11 @@ int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
 	mei_hdr.reserved = 0;
 	mei_hdr.internal = cb->internal;
 
-	if (slots >= msg_slots) {
+	if ((u32)slots >= msg_slots) {
 		mei_hdr.length = len;
 		mei_hdr.msg_complete = 1;
 	/* Split the message only if we can write the whole host buffer */
-	} else if (slots == dev->hbuf_depth) {
+	} else if ((u32)slots == dev->hbuf_depth) {
 		msg_slots = slots;
 		len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
 		mei_hdr.length = len;
diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index 334ab02e1de2..a12b464bc0b4 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -540,8 +540,11 @@ static int mei_me_hbuf_write(struct mei_device *dev,
 	empty_slots = mei_hbuf_empty_slots(dev);
 	dev_dbg(dev->dev, "empty slots = %hu.\n", empty_slots);
 
+	if (empty_slots < 0)
+		return -EOVERFLOW;
+
 	dw_cnt = mei_data2slots(length);
-	if (empty_slots < 0 || dw_cnt > empty_slots)
+	if (dw_cnt > (u32)empty_slots)
 		return -EMSGSIZE;
 
 	mei_me_hcbww_write(dev, *((u32 *) header));
diff --git a/drivers/misc/mei/hw-txe.c b/drivers/misc/mei/hw-txe.c
index c2c8993e2a51..4c1acf68089e 100644
--- a/drivers/misc/mei/hw-txe.c
+++ b/drivers/misc/mei/hw-txe.c
@@ -709,7 +709,7 @@ static int mei_txe_write(struct mei_device *dev,
 	struct mei_txe_hw *hw = to_txe_hw(dev);
 	unsigned long rem;
 	unsigned long length;
-	int slots = dev->hbuf_depth;
+	u32 slots = dev->hbuf_depth;
 	u32 *reg_buf = (u32 *)buf;
 	u32 dw_cnt;
 	int i;
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index b0b8f18a85e3..01990e339e76 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -173,10 +173,12 @@ static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 	int slots;
 	int ret;
 
-	slots = mei_hbuf_empty_slots(dev);
 	msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
+	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
 
-	if (slots < msg_slots)
+	if ((u32)slots < msg_slots)
 		return -EMSGSIZE;
 
 	ret = mei_hbm_cl_disconnect_rsp(dev, cl);
@@ -208,8 +210,10 @@ static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 
 	msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 	slots = mei_hbuf_empty_slots(dev);
+	if (slots < 0)
+		return -EOVERFLOW;
 
-	if (slots < msg_slots)
+	if ((u32)slots < msg_slots)
 		return -EMSGSIZE;
 
 	ret = mei_hbm_cl_flow_control_req(dev, cl);
@@ -365,7 +369,10 @@ int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list)
 		return 0;
 
 	slots = mei_hbuf_empty_slots(dev);
-	if (slots <= 0)
+	if (slots < 0)
+		return -EOVERFLOW;
+
+	if (slots == 0)
 		return -EMSGSIZE;
 
 	/* complete all waiting for write CB */