From: Ilpo Järvinen ilpo.jarvinen@linux.intel.com
commit e8914b52e5b024e4af3d810a935fe0805eee8a36 upstream.
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 Link: https://lore.kernel.org/r/20230103093435.4396-1-ilpo.jarvinen@linux.intel.co... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/pch_uart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/tty/serial/pch_uart.c +++ b/drivers/tty/serial/pch_uart.c @@ -806,7 +806,7 @@ static void pch_dma_tx_complete(void *ar } xmit->tail &= UART_XMIT_SIZE - 1; 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;