[PATCH 1/2] serial: stm32: reset dma buffers during probe

[Greg Kroah-Hartman]

On Thu, May 27, 2021 at 11:15:36AM +0200, Erwan Le Ray wrote:
> Reset Rx and Tx dma buffers during probe to avoid freeing
> invalid buffer in no dma mode.
> 
> Signed-off-by: Erwan Le Ray <erwan.leray at foss.st.com>
> 
> diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
> index c2ae7b392b86..2ac3b30477a7 100644
> --- a/drivers/tty/serial/stm32-usart.c
> +++ b/drivers/tty/serial/stm32-usart.c
> @@ -1168,6 +1168,8 @@ static struct stm32_port *stm32_usart_of_get_port(struct platform_device *pdev)
>  	stm32_ports[id].cr1_irq = USART_CR1_RXNEIE;
>  	stm32_ports[id].cr3_irq = 0;
>  	stm32_ports[id].last_res = RX_BUF_L;
> +	stm32_ports[id].rx_dma_buf = 0;
> +	stm32_ports[id].tx_dma_buf = 0;
>  	return &stm32_ports[id];
>  }
>  
> -- 
> 2.17.1
> 

Is this a bugfix?  if so, what commit does this fix and does it need to
be backported anywhere?

thanks,

greg k-h