Re: [RFC] Resolving "false positive" error message from checkpatch.pl

On Feb 03, 2017 11:27, Greg KH wrote:

On Fri, Feb 03, 2017 at 11:11:35AM +0100, Slawomir Stepien wrote:

quoted

Hi all

There is a "false positive" error reported by checkpatch.pl:

ERROR: Use 4 digit octal (0777) not decimal permissions
#272: FILE: drivers/staging/iio/meter/ade7759.c:272:
+static IIO_DEV_ATTR_CH_OFF(1, S_IWUSR | S_IRUGO,
+		ade7759_read_8bit,
+		ade7759_write_8bit,
+		ADE7759_CH1OS);

ERROR: Use 4 digit octal (0777) not decimal permissions
#276: FILE: drivers/staging/iio/meter/ade7759.c:276:
+static IIO_DEV_ATTR_CH_OFF(2, S_IWUSR | S_IRUGO,
+		ade7759_read_8bit,
+		ade7759_write_8bit,
+		ADE7759_CH2OS);

The same for the file drivers/staging/iio/meter/ade7753.c.

We can see that this macro is matched by the pattern "IIO_DEV_ATTR_[A-Z_]+" from
@mode_permission_funcs in checkpatch.pl.

My question is: how this should be fixed?

Why do you think this is a false-positive?

Because the 1st arg of that macro is not supposed to be a permissions flags.

quoted

From what I can say, it's a false positive so the correct way to fix it is to
change the matching pattern: "IIO_DEV_ATTR_(?!CH_OFF)[A-Z_]+".

Huh?

Provide a patch to show what you are suggesting please.

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 8e96af53611c..0a1c6ec86caa 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl

@@ -525,7 +525,7 @@ our @mode_permission_funcs = (
 	["debugfs_create_(?:file|u8|u16|u32|u64|x8|x16|x32|x64|size_t|atomic_t|bool|blob|regset32|u32_array)", 2],
 	["proc_create(?:_data|)", 2],
 	["(?:CLASS|DEVICE|SENSOR|SENSOR_DEVICE|IIO_DEVICE)_ATTR", 2],
-	["IIO_DEV_ATTR_[A-Z_]+", 1],
+	["IIO_DEV_ATTR_(?!CH_OFF)[A-Z_]+", 1],
 	["SENSOR_(?:DEVICE_|)ATTR_2", 2],
 	["SENSOR_TEMPLATE(?:_2|)", 3],
 	["__ATTR", 2],

-- 
2.11.0