From: Xiongfeng Wang wangxiongfeng2@huawei.com
[ Upstream commit 8be3a7bf773700534a6e8f87f6ed2ed111254be5 ]
As comment of pci_get_slot() says, it returns a pci_device with its refcount increased. The caller must decrement the reference count by calling pci_dev_put().
Since 'dma_dev' is only used to filter the channel in filter(), we can call pci_dev_put() before exiting from pch_request_dma(). Add the missing pci_dev_put() for the normal and error path.
Fixes: 3c6a483275f4 ("Serial: EG20T: add PCH_UART driver") Signed-off-by: Xiongfeng Wang wangxiongfeng2@huawei.com Link: https://lore.kernel.org/r/20221122114559.27692-1-wangxiongfeng2@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/pch_uart.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index c59ce7886579..b17788cf309b 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -694,6 +694,7 @@ static void pch_request_dma(struct uart_port *port) if (!chan) { dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Tx)\n", __func__); + pci_dev_put(dma_dev); return; } priv->chan_tx = chan; @@ -710,6 +711,7 @@ static void pch_request_dma(struct uart_port *port) __func__); dma_release_channel(priv->chan_tx); priv->chan_tx = NULL; + pci_dev_put(dma_dev); return; }
@@ -717,6 +719,8 @@ static void pch_request_dma(struct uart_port *port) priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize, &priv->rx_buf_dma, GFP_KERNEL); priv->chan_rx = chan; + + pci_dev_put(dma_dev); }
static void pch_dma_rx_complete(void *arg)