The to-be-fixed commit removed locking when invalidating the DMA RX descriptors on shutdown. It overlooked that there is still a rx_timer running which may still access the protected data. So, re-add the locking. Reported-by: Dirk Behme <dirk.behme@xxxxxxxxxxxx> Closes: https://lore.kernel.org/r/ee6c9e16-9f29-450e-81da-4a8dceaa8fc7@xxxxxxxxxxxx Fixes: 2c4ee23530ff ("serial: sh-sci: Postpone DMA release when falling back to PIO") Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/sh-sci.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index e512eaa57ed5..a6f3517dce74 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1271,9 +1271,14 @@ static void sci_dma_rx_chan_invalidate(struct sci_port *s) static void sci_dma_rx_release(struct sci_port *s) { struct dma_chan *chan = s->chan_rx_saved; + struct uart_port *port = &s->port; + unsigned long flags; + uart_port_lock_irqsave(port, &flags); s->chan_rx_saved = NULL; sci_dma_rx_chan_invalidate(s); + uart_port_unlock_irqrestore(port, flags); + dmaengine_terminate_sync(chan); dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0], sg_dma_address(&s->sg_rx[0])); -- 2.43.0
