A local variable sg is used to store scatterlist pointer in pch_dma_tx_complete(). The for loop doing Tx byte accounting before dma_unmap_sg() alters sg in its increment statement. Therefore, the pointer passed into dma_unmap_sg() won't match to the one given to dma_map_sg().

To fix the problem, use priv->sg_tx_p directly in dma_unmap_sg() instead of the local variable.

Fixes: da3564ee027e ("pch_uart: add multi-scatter processing") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com --- drivers/tty/serial/pch_uart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c index 3d54a43768cd..9576ba8bbc40 100644 --- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -749,7 +749,7 @@ static void pch_dma_tx_complete(void *arg) uart_xmit_advance(port, sg_dma_len(sg));

async_tx_ack(priv->desc_tx); - dma_unmap_sg(port->dev, sg, priv->orig_nent, DMA_TO_DEVICE); + dma_unmap_sg(port->dev, priv->sg_tx_p, priv->orig_nent, DMA_TO_DEVICE); priv->tx_dma_use = 0; priv->nent = 0; priv->orig_nent = 0;