From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 1/1] lan78xx: Fix Smatch warnings
Date: Sun, 09 Aug 2015 22:43:18 -0700 (PDT)
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Cc: netdev@vger.kernel.org, dan.carpenter@oracle.com
To: Woojung.Huh@microchip.com
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From: <Woojung.Huh@microchip.com>
Date: Wed, 5 Aug 2015 21:26:14 +0000

> diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
> index ec8bd34..3ac405f 100644
> --- a/drivers/net/usb/lan78xx.c
> +++ b/drivers/net/usb/lan78xx.c
> @@ -291,7 +291,7 @@ static int lan78xx_read_reg(struct lan78xx_net *dev, u32 index, u32 *data)
>  	u32 *buf = kmalloc(sizeof(u32), GFP_KERNEL);
>  	int ret;
>  
> -	BUG_ON(!dev);
> +	WARN_ON_ONCE(!dev);
>  

The debugging check makes no sense at all if you aren't going to crash
immediately due to it.

The subsequent dereference of dev will cause a crash anyways.

So if you're going to change this at all, just kill all of these
NULL pointer debug checks, as they are completely pointless.