Re: [PATCH 1/2]drivers/usb/core/sysfs.c Fix variable 'retval' setbut not used

From: Justin P. Mattock
Date: Tue Aug 03 2010 - 10:43:46 EST

On 08/03/2010 07:29 AM, Alan Stern wrote:
On Tue, 3 Aug 2010 Valdis.Kletnieks@xxxxxx wrote:

On Mon, 02 Aug 2010 21:26:28 PDT, "Justin P. Mattock" said:
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c

if (alt->string)
- retval = device_create_file(&intf->dev,&dev_attr_interface);
+ device_create_file(&intf->dev,&dev_attr_interface);
intf->sysfs_files_created = 1;
return 0;

Justin, did you try compiling your new code? Those unused values are
there because device_create_file is declared as __must_check.

I went as far as compiling, once I saw no warning then figured o.k
I'll send out what I have for feedback then go from there.
(and just for the record I want to thank those who took the time to go through and give feedback).

What should the code do if device_create_file() manages to fail? Yes, ignoring
the return value is one option, but is it the best one? 'return ret;' might be
another one. Somebody who understands this code and has more caffeine than me
should look this over.

Failure to create a file in sysfs is almost never fatal and usually not
even dangerous. Ignoring the error is generally better than failing
the entire operation.

Alan Stern

ahh.. you made this more clear for me.. cool thanks!

Justin P. Mattock
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