Hi Markus,

[auto build test WARNING on s390/features]
[also build test WARNING on v4.8-rc4 next-20160825]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]

url:    https://github.com/0day-ci/linux/commits/SF-Markus-Elfring/s390-debug-Fine-tuning-for-several-function-implementations/20160903-204622
base:   https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git features
config: s390-allmodconfig (attached as .config)
compiler: s390x-linux-gnu-gcc (Debian 5.4.0-6) 5.4.0 20160609
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=s390 

All warnings (new ones prefixed by >>):

   arch/s390/kernel/debug.c: In function 'debug_get_user_string':
>> arch/s390/kernel/debug.c:1167:10: warning: return makes pointer from integer without a cast [-Wint-conversion]
      return PTR_ERR(buffer);
             ^

vim +1167 arch/s390/kernel/debug.c

  1151			id->debugfs_entries[i] = NULL;
  1152		}
  1153		spin_unlock_irqrestore(&id->lock, flags);
  1154		debugfs_remove(dentry);
  1155	out:
  1156		return rc;
  1157	}
  1158	EXPORT_SYMBOL(debug_unregister_view);
  1159	
  1160	static inline char *
  1161	debug_get_user_string(const char __user *user_buf, size_t user_len)
  1162	{
  1163		char* buffer;
  1164	
  1165		buffer = memdup_user(user_buf, user_len + 1);
  1166		if (IS_ERR(buffer))
> 1167			return PTR_ERR(buffer);
  1168		/* got the string, now strip linefeed. */
  1169		if (buffer[user_len - 1] == '\n')
  1170			buffer[user_len - 1] = 0;
  1171		else
  1172			buffer[user_len] = 0;
  1173		return buffer;
  1174	}
  1175	

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0-DAY kernel test infrastructure                Open Source Technology Center
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