On Thu, Apr 20, 2017 at 09:46:03AM +0200, Richard Genoud wrote: > On 20/04/2017 08:35, Greg Kroah-Hartman wrote: > > 3.18-stable review patch. If anyone has any objections, please let me know. > > > > ------------------ > > > > From: Richard Genoud <richard.gen...@gmail.com> > > > > 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.fe...@microchip.com> > > Signed-off-by: Richard Genoud <richard.gen...@gmail.com> > > Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> > > > > --- > > drivers/tty/serial/atmel_serial.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > --- a/drivers/tty/serial/atmel_serial.c > > +++ b/drivers/tty/serial/atmel_serial.c > > @@ -1867,6 +1867,11 @@ static void atmel_flush_buffer(struct ua > > 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 tx_len accordingly. > > + */ > > + atmel_port->tx_len = 0; > > } > > > > /* > > > > > Hi, > This won't compile on 3.18 kernel since ->tx_len doesn't exist yet. > > Here is the backported version of this patch: > Thanks ! > ====================== > > 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 > its length. > That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE - > sg_dma_len(&atmel_port->sg_tx)) bytes). > > Signed-off-by: Richard Genoud <richard.gen...@gmail.com> > --- > 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 daaed7c79e4f..a10c778be2ad 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -1867,6 +1867,11 @@ 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;
Thanks for the fix, now updated. greg k-h
