diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 52bb21205bb682..5ab8b05e87ac28 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -41,6 +41,7 @@ struct uart_8250_dma {
 	dma_cookie_t		tx_cookie;
 
 	void			*rx_buf;
+	void			*tx_buf;
 
 	size_t			rx_size;
 	size_t			tx_size;
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
index 890fa7ddaa7f36..5988fc10b6c520 100644
--- a/drivers/tty/serial/8250/8250_dma.c
+++ b/drivers/tty/serial/8250/8250_dma.c
@@ -8,6 +8,7 @@
 #include <linux/tty_flip.h>
 #include <linux/serial_reg.h>
 #include <linux/dma-mapping.h>
+#include <linux/slab.h>
 
 #include "8250.h"
 
@@ -65,6 +66,9 @@ int serial8250_tx_dma(struct uart_8250_port *p)
 	struct circ_buf			*xmit = &p->port.state->xmit;
 	struct dma_async_tx_descriptor	*desc;
 	int ret;
+	size_t				chunk1;
+	size_t 				chunk2;
+	int				head;
 
 	if (dma->tx_running)
 		return 0;
@@ -75,10 +79,18 @@ int serial8250_tx_dma(struct uart_8250_port *p)
 		return 0;
 	}
 
-	dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	head = xmit->head;
+	chunk1 = CIRC_CNT_TO_END(head, xmit->tail, UART_XMIT_SIZE);
+	memcpy(dma->tx_buf, xmit->buf + xmit->tail, chunk1);
+	
+	chunk2 = CIRC_CNT(head, xmit->tail, UART_XMIT_SIZE) - chunk1;
+	if (chunk2 > 0) {
+		memcpy(dma->tx_buf + chunk1, xmit->buf, chunk2);
+	}
+	dma->tx_size = chunk1 + chunk2;
 
 	desc = dmaengine_prep_slave_single(dma->txchan,
-					   dma->tx_addr + xmit->tail,
+					   dma->tx_addr,
 					   dma->tx_size, DMA_MEM_TO_DEV,
 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!desc) {
@@ -217,20 +229,27 @@ int serial8250_request_dma(struct uart_8250_port *p)
 	}
 
 	/* TX buffer */
+	dma->tx_buf = kmalloc(UART_XMIT_SIZE, GFP_KERNEL);
+	if (!dma->tx_buf) {
+		ret = -ENOMEM;
+		goto free_coherent_rx;
+	}
+
 	dma->tx_addr = dma_map_single(dma->txchan->device->dev,
-					p->port.state->xmit.buf,
+					dma->tx_buf,
 					UART_XMIT_SIZE,
 					DMA_TO_DEVICE);
 	if (dma_mapping_error(dma->txchan->device->dev, dma->tx_addr)) {
-		dma_free_coherent(dma->rxchan->device->dev, dma->rx_size,
-				  dma->rx_buf, dma->rx_addr);
 		ret = -ENOMEM;
-		goto err;
+		goto free_coherent_rx;
 	}
 
 	dev_dbg_ratelimited(p->port.dev, "got both dma channels\n");
 
 	return 0;
+free_coherent_rx:
+	dma_free_coherent(dma->rxchan->device->dev, dma->rx_size,
+				dma->rx_buf, dma->rx_addr);
 err:
 	dma_release_channel(dma->txchan);
 release_rx:
@@ -257,6 +276,8 @@ void serial8250_release_dma(struct uart_8250_port *p)
 	dmaengine_terminate_sync(dma->txchan);
 	dma_unmap_single(dma->txchan->device->dev, dma->tx_addr,
 			 UART_XMIT_SIZE, DMA_TO_DEVICE);
+	kfree(dma->tx_buf);
+	dma->tx_buf = NULL;
 	dma_release_channel(dma->txchan);
 	dma->txchan = NULL;
 	dma->tx_running = 0;