Hi Willy, You can drop this patch. There's nothing to fix on 3.10.x since the DMA TX support has been introduced in 3.12. Thanks ! 2017-06-19 20:31 GMT+02:00 Willy Tarreau <w@xxxxxx>: > From: Richard Genoud <richard.genoud@xxxxxxxxx> > > commit 31ca2c63fdc0aee725cbd4f207c1256f5deaabde upstream. > > If uart_flush_buffer() is called between atmel_tx_dma() and > atmel_complete_tx_dma(), the circular buffer has been cleared, but not > atmel_port->tx_len. > That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE - > atmel_port->tx_len) bytes). > > Tested-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> > [rg] backport to 3.12 > Signed-off-by: Richard Genoud <richard.genoud@xxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Willy Tarreau <w@xxxxxx> > --- > drivers/tty/serial/atmel_serial.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c > index 82127ac..41d1df5 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -1090,6 +1090,11 @@ static void atmel_flush_buffer(struct uart_port *port) > UART_PUT_TCR(port, 0); > atmel_port->pdc_tx.ofs = 0; > } > + /* > + * in uart_flush_buffer(), the xmit circular buffer has just > + * been cleared, so we have to reset its length accordingly. > + */ > + sg_dma_len(&atmel_port->sg_tx) = 0; > } > > /* > -- > 2.8.0.rc2.1.gbe9624a >