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

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

[Mathieu Malaterre]

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 ‘ret’ set but not used [-Wunused-but-set-variable]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
---
 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
-- 
2.11.0

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

[Shawn Lin]

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 ‘ret’ 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. And it's worth backporting to stable.

Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>

> Signed-off-by: Mathieu Malaterre <malat@debian.org>
> ---
>   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
> 

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@rock-chips.com> 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 ‘ret’ 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@vger.kernel.org> # v4.15+

?

> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
>
>
>> Signed-off-by: Mathieu Malaterre <malat@debian.org>
>> ---
>>   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
>>
>

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

[Shawn Lin]

On 2018/5/17 14:16, Mathieu Malaterre wrote:
> On Thu, May 17, 2018 at 4:45 AM, Shawn Lin <shawn.lin@rock-chips.com> 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 ‘ret’ 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.
> 

Thanks for sharing.

> 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@vger.kernel.org> # v4.15+
> 

In general Ulf could kindly help with it when applied. :)

> ?
> 
>> Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
>>
>>
>>> Signed-off-by: Mathieu Malaterre <malat@debian.org>
>>> ---
>>>    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
>>>
>>
> --
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> 
> 
> 

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

[Ulf Hansson]

On 16 May 2018 at 21:20, Mathieu Malaterre <malat@debian.org> 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 ‘ret’ set but not used [-Wunused-but-set-variable]
>
> Signed-off-by: Mathieu Malaterre <malat@debian.org>

Thanks, applied for fixes and by adding a stable tag!

Kind regards
Uffe

> ---
>  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
> --
> 2.11.0
>