From: Michael Walle Date: Fri, 3 Apr 2020 17:49:42 +0000 (+0200) Subject: tty: serial: fsl_lpuart: make coverity happy X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=810bc0a5fafb8575b9406fcc8b0be77ff93a7be0;p=linux.git tty: serial: fsl_lpuart: make coverity happy Coverity reports the following: var_compare_op: Comparing chan to null implies that chan might be null. 1234 if (chan) 1235 dmaengine_terminate_all(chan); 1236 Dereference after null check (FORWARD_NULL) var_deref_op: Dereferencing null pointer chan. 1237 dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE); Technically, this is correct. But lpuart_dma_rx_free() is guarded by lpuart_dma_rx_use which is only true if there is a dma channel, see lpuart_rx_dma_startup(). In any way, this looks bogus. So remove the superfluous "if (chan)" check and make coverity happy. Fixes: a092ab25fdaa ("tty: serial: fsl_lpuart: fix DMA mapping") Signed-off-by: Michael Walle Reported-by: Colin Ian King Acked-by: Jiri Slaby Reviewed-by: Fabio Estevam Link: https://lore.kernel.org/r/20200403174942.9594-1-michael@walle.cc Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 5d41075964f2c..dba730d1801f6 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -1231,9 +1231,7 @@ static void lpuart_dma_rx_free(struct uart_port *port) struct lpuart_port, port); struct dma_chan *chan = sport->dma_rx_chan; - if (chan) - dmaengine_terminate_all(chan); - + dmaengine_terminate_all(chan); dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE); kfree(sport->rx_ring.buf); sport->rx_ring.tail = 0;