Re: [PATCH] net: stmmac: Fix signedness bug in stmmac_probe_config_dt()

[Yuehaibing]

On 2020/8/18 22:51, Andreas Schwab wrote:
> On Aug 18 2020, YueHaibing wrote:
> 
>> The "plat->phy_interface" variable is an enum and in this context GCC
>> will treat it as an unsigned int so the error handling is never
>> triggered.
>>
>> Fixes: b9f0b2f634c0 ("net: stmmac: platform: fix probe for ACPI devices")
>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
>> ---
>>  drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> index f32317fa75c8..b5b558b02e7d 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
>> @@ -413,7 +413,7 @@ stmmac_probe_config_dt(struct platform_device *pdev, const char **mac)
>>  	}
>>  
>>  	plat->phy_interface = device_get_phy_mode(&pdev->dev);
>> -	if (plat->phy_interface < 0)
>> +	if ((int)plat->phy_interface < 0)
>>  		return ERR_PTR(plat->phy_interface);
> 
> I don't think the conversion to long when passed to ERR_PTR will produce
> a negative value either (if long is wider than unsigned int).

Thanks, will respin.
> 
> Andreas.
>