[PATCH] net: dsa: mv88e6xxx: fix uninit-value err in mv88e6393x_serdes_power

From: Jackie Liu <redacted>

'err' is not initialized. If the value of cmode is not in the switch case,
it will cause a logic error and return early.

Fixes: 7527d66260ac ("net: dsa: mv88e6xxx: Save power by disabling SerDes trasmitter and receiver")
Reported-by: kernel-bot <redacted>
Signed-off-by: Jackie Liu <redacted>
---
 drivers/net/dsa/mv88e6xxx/serdes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 55273013bfb5..33727439724a 100644
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c

@@ -1507,7 +1507,7 @@ int mv88e6393x_serdes_power(struct mv88e6xxx_chip *chip, int port, int lane,
 			    bool on)
 {
 	u8 cmode = chip->ports[port].cmode;
-	int err;
+	int err = 0;
 
 	if (port != 0 && port != 9 && port != 10)
 		return -EOPNOTSUPP;

-- 
2.25.1

On Mon, Dec 06, 2021 at 06:13:52PM +0800, Jackie Liu wrote:

From: Jackie Liu <redacted>

'err' is not initialized. If the value of cmode is not in the switch case,
it will cause a logic error and return early.

Same fix as: [off-list ref]

At least here some analysis has been done why there is a warning.

Should we add a default?

       Andrew

On Mon, 6 Dec 2021 14:45:11 +0100
Andrew Lunn [off-list ref] wrote:

On Mon, Dec 06, 2021 at 06:13:52PM +0800, Jackie Liu wrote:

quoted

From: Jackie Liu <redacted>

'err' is not initialized. If the value of cmode is not in the switch case,
it will cause a logic error and return early.  

Same fix as: [off-list ref]

At least here some analysis has been done why there is a warning.

Should we add a default?

       Andrew

indeed it should be err=0