lan9303: Fix read error execution path

[PATCH net-next] lan9303: Fix read error execution path

Posted by Jerry Ray 2 years, 9 months ago

This patch fixes an issue where a read failure of a port statistic counter
will return unknown results.  While it is highly unlikely the read will
ever fail, it is much cleaner to return a zero for the stat count.

Fixes: a1292595e006 ("net: dsa: add new DSA switch driver for the SMSC-LAN9303")

Signed-off-by: Jerry Ray <jerry.ray@microchip.com>
---
 drivers/net/dsa/lan9303-core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
index 80f07bd20593..2e270b479143 100644
--- a/drivers/net/dsa/lan9303-core.c
+++ b/drivers/net/dsa/lan9303-core.c
@@ -1005,9 +1005,11 @@ static void lan9303_get_ethtool_stats(struct dsa_switch *ds, int port,
 		ret = lan9303_read_switch_port(
 			chip, port, lan9303_mib[u].offset, &reg);
 
-		if (ret)
+		if (ret) {
 			dev_warn(chip->dev, "Reading status port %d reg %u failed\n",
 				 port, lan9303_mib[u].offset);
+			reg = 0;
+		}
 		data[u] = reg;
 	}
 }
-- 
2.17.1

Re: [PATCH net-next] lan9303: Fix read error execution path

Posted by Vladimir Oltean 2 years, 9 months ago

Is it deliberate that you are targeting the "net-next" tree for new
features rather than "net" for bug fixes?

On Thu, Dec 08, 2022 at 01:30:05PM -0600, Jerry Ray wrote:
> This patch fixes an issue where a read failure of a port statistic counter
> will return unknown results.  While it is highly unlikely the read will
> ever fail, it is much cleaner to return a zero for the stat count.
> 
> Fixes: a1292595e006 ("net: dsa: add new DSA switch driver for the SMSC-LAN9303")
> 

There shouldn't be blank lines between the tags of a commit, see "git log"
for examples.

Not a reason in itself to resend, AFAIK.

> Signed-off-by: Jerry Ray <jerry.ray@microchip.com>
> ---
>  drivers/net/dsa/lan9303-core.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c
> index 80f07bd20593..2e270b479143 100644
> --- a/drivers/net/dsa/lan9303-core.c
> +++ b/drivers/net/dsa/lan9303-core.c
> @@ -1005,9 +1005,11 @@ static void lan9303_get_ethtool_stats(struct dsa_switch *ds, int port,
>  		ret = lan9303_read_switch_port(
>  			chip, port, lan9303_mib[u].offset, &reg);
>  
> -		if (ret)
> +		if (ret) {
>  			dev_warn(chip->dev, "Reading status port %d reg %u failed\n",
>  				 port, lan9303_mib[u].offset);
> +			reg = 0;
> +		}
>  		data[u] = reg;
>  	}
>  }
> -- 
> 2.17.1
>