From:   Johan Hovold <johan+linaro@kernel.org>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Bjorn Andersson <andersson@kernel.org>,
        Andy Gross <agross@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
        Douglas Anderson <dianders@chromium.org>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Johan Hovold <johan+linaro@kernel.org>
Subject: [PATCH 2/4] serial: qcom-geni: fix DMA mapping leak on shutdown
Date:   Tue,  7 Mar 2023 17:44:03 +0100
Message-Id: <20230307164405.14218-3-johan+linaro@kernel.org>
In-Reply-To: <20230307164405.14218-1-johan+linaro@kernel.org>
References: <20230307164405.14218-1-johan+linaro@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Fix what appears to be a copy-paste error that can lead to a leaked DMA
mapping on close() and failure to restart TX after the port is reopened.

Note that rx_dma_addr is generally NULL when
qcom_geni_serial_stop_tx_dma() is called as part of shutdown() (but
tx_dma_addr need not be).

Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/tty/serial/qcom_geni_serial.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 11da05d8f848..2aa3872e6283 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -596,7 +596,7 @@ static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport)
 	if (!qcom_geni_serial_main_active(uport))
 		return;
 
-	if (port->rx_dma_addr) {
+	if (port->tx_dma_addr) {
 		geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr,
 				      port->tx_remaining);
 		port->tx_dma_addr = 0;
-- 
2.39.2