serial: 8250_dma: terminate correct DMA in tx_dma_flush()

johnkeeping · gregkh · commit 1a8d68ca7752 · 2025-04-07T10:05:46.000+02:00
commit a26503092c75abba70a0be2aa01145ecf90c2a22 upstream. When flushing transmit side DMA, it is the transmit channel that should be terminated, not the receive channel. Fixes: 9e512eaaf8f40 ("serial: 8250: Fix fifo underflow on flush") Cc: stable <stable@kernel.org> Reported-by: Wentao Guan <guanwentao@uniontech.com> Signed-off-by: John Keeping <jkeeping@inmusicbrands.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20250224121831.1429323-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
@@ -146,7 +146,7 @@ void serial8250_tx_dma_flush(struct uart_8250_port *p)
 	 */
 	dma->tx_size = 0;
 
-	dmaengine_terminate_async(dma->rxchan);
+	dmaengine_terminate_async(dma->txchan);
 }
 
 int serial8250_rx_dma(struct uart_8250_port *p)

Original file line number	Diff line number	Diff line change
`@@ -146,7 +146,7 @@ void serial8250_tx_dma_flush(struct uart_8250_port *p)`
`146`	`146`	`*/`
`147`	`147`	`dma->tx_size = 0;`
`148`	`148`
`149`		`- dmaengine_terminate_async(dma->rxchan);`
	`149`	`+ dmaengine_terminate_async(dma->txchan);`
`150`	`150`	`}`
`151`	`151`
`152`	`152`	`int serial8250_rx_dma(struct uart_8250_port *p)`