Re: [PATCH] mmc: block: propagate correct returned value in mmc_rpmb_ioctl

[Mathieu Malaterre]

On Thu, May 17, 2018 at 4:45 AM, Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> wrote:
>
> On 2018/5/17 3:20, Mathieu Malaterre wrote:
>>
>> In commit 97548575bef3 ("mmc: block: Convert RPMB to a character device")
>> a
>> new function `mmc_rpmb_ioctl` was added. The final return is simply
>> returning a value of `0` instead of propagating the correct return code.
>>
>> Discovered during a compilation with W=1, silence the following gcc
>> warning
>>
>>    drivers/mmc/core/block.c:2470:6: warning: variable âretâ set but not
>> used [-Wunused-but-set-variable]
>>
>
> Good catch! But hey, which gcc are you using now? Mine, gcc-linaro-
> 6.3.1-2017.05-x86_64_aarch64-linux-gnu, with W=1 doesn't warn about
> this.

$ powerpc-linux-gnu-gcc --version
powerpc-linux-gnu-gcc (Debian 6.3.0-18) 6.3.0 20170516
Copyright (C) 2016 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

This is the default powerpc cross compiler on Debian stable (no
change). Config is simply a ppc32 (with some minor customization).


> And it's worth backporting to stable.

I am not familiar with the process, do I need to submit a v2 to add the line:

Cc: <stable@xxxxxxxxxxxxxxx> # v4.15+

?

> Reviewed-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
>
>
>> Signed-off-by: Mathieu Malaterre <malat@xxxxxxxxxx>
>> ---
>>   drivers/mmc/core/block.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
>> index 9e923cd1d80e..38a7586b00cc 100644
>> --- a/drivers/mmc/core/block.c
>> +++ b/drivers/mmc/core/block.c
>> @@ -2485,7 +2485,7 @@ static long mmc_rpmb_ioctl(struct file *filp,
>> unsigned int cmd,
>>                 break;
>>         }
>>   -     return 0;
>> +       return ret;
>>   }
>>     #ifdef CONFIG_COMPAT
>>
>