On Fri, Jun 30, 2017 at 02:13:29PM +0200, Lothar Wa?mann wrote:

Hi,

On Fri, 30 Jun 2017 14:04:42 +0200 Romain Perier wrote:

quoted

From: Nandor Han <redacted>

Initialize both dma_is_{rx|tx}ing variables when DMA is enabled to avoid
checking uninitialized variables if port shutdown is requested before
DMA channels get a chance to start.

Signed-off-by: Nandor Han <redacted>
Signed-off-by: Romain Perier <redacted>
---
 drivers/tty/serial/imx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 188063d..81fb413 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c

@@ -1225,6 +1225,9 @@ static void imx_enable_dma(struct imx_port *sport)
 
 	imx_setup_ufcr(sport, TXTL_DMA, RXTL_DMA);
 
+	sport->dma_is_rxing = 0;
+	sport->dma_is_txing = 0;
+
 	sport->dma_is_enabled = 1;
 }
 

sport is devm_kzalloc()ed, so the variables are initialized to 0 anyway.

I'd agree to Lothar's statement. Did you find this issue by inspection,
or does it fix a compiler warning? Do you think there is an actual
problem?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |