[PATCH] checkpatch.pl: Warn on duplicate sysctl local variable

[PATCH] checkpatch.pl: Warn on duplicate sysctl local variable

[Matteo Croce]

Commit 6a33853c5773 ("proc/sysctl: add shared variables for range check")
adds some shared const variables to be used instead of a local copy in
each source file.
Warn when a chunk duplicates one of these values in a ctl_table struct:

    $ scripts/checkpatch.pl 0001-test-commit.patch
    WARNING: duplicated sysctl range checking value 'zero', consider using the shared one in include/linux/sysctl.h
    #27: FILE: arch/arm/kernel/isa.c:48:
    +               .extra1         = &zero,

    WARNING: duplicated sysctl range checking value 'int_max', consider using the shared one in include/linux/sysctl.h
    #28: FILE: arch/arm/kernel/isa.c:49:
    +               .extra2         = &int_max,

    total: 0 errors, 2 warnings, 14 lines checked

Signed-off-by: Matteo Croce <mcroce@redhat.com>
---
 scripts/checkpatch.pl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 342c7c781ba5..b986bab32af7 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6639,6 +6639,13 @@ sub process {
 				     "unknown module license " . $extracted_string . "\n" . $herecurr);
 			}
 		}
+
+# check for sysctl duplicate constants
+		if ($line =~ /\.extra[12]\s*=\s*&(zero|one|int_max|max_int)\b/) {
+			my $extracted_string = get_quoted_string($line, $rawline);
+			WARN("DUPLICATED_SYSCTL_CONST",
+				"duplicated sysctl range checking value '$1', consider using the shared one in include/linux/sysctl.h" . $extracted_string . "\n" . $herecurr);
+		}
 	}
 
 	# If we have no input at all, then there is nothing to report on
-- 
2.21.0

Re: [PATCH] checkpatch.pl: Warn on duplicate sysctl local variable

[Joe Perches]

On Fri, 2019-05-31 at 01:51 +0200, Matteo Croce wrote:
> Commit 6a33853c5773 ("proc/sysctl: add shared variables for range check")
> adds some shared const variables to be used instead of a local copy in
> each source file.
> Warn when a chunk duplicates one of these values in a ctl_table struct:
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -6639,6 +6639,13 @@ sub process {
>  				     "unknown module license " . $extracted_string . "\n" . $herecurr);
>  			}
>  		}
> +
> +# check for sysctl duplicate constants
> +		if ($line =~ /\.extra[12]\s*=\s*&(zero|one|int_max|max_int)\b/) {
> +			my $extracted_string = get_quoted_string($line, $rawline);
> +			WARN("DUPLICATED_SYSCTL_CONST",
> +				"duplicated sysctl range checking value '$1', consider using the shared one in include/linux/sysctl.h" . $extracted_string . "\n" . $herecurr);
> +		}

why is $extracted_string used here?

Re: [PATCH] checkpatch.pl: Warn on duplicate sysctl local variable

[Matteo Croce]

On Fri, May 31, 2019 at 2:55 AM Joe Perches <joe@perches.com> wrote:
>
> On Fri, 2019-05-31 at 01:51 +0200, Matteo Croce wrote:
> > Commit 6a33853c5773 ("proc/sysctl: add shared variables for range check")
> > adds some shared const variables to be used instead of a local copy in
> > each source file.
> > Warn when a chunk duplicates one of these values in a ctl_table struct:
> []
> > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> []
> > @@ -6639,6 +6639,13 @@ sub process {
> >                                    "unknown module license " . $extracted_string . "\n" . $herecurr);
> >                       }
> >               }
> > +
> > +# check for sysctl duplicate constants
> > +             if ($line =~ /\.extra[12]\s*=\s*&(zero|one|int_max|max_int)\b/) {
> > +                     my $extracted_string = get_quoted_string($line, $rawline);
> > +                     WARN("DUPLICATED_SYSCTL_CONST",
> > +                             "duplicated sysctl range checking value '$1', consider using the shared one in include/linux/sysctl.h" . $extracted_string . "\n" . $herecurr);
> > +             }
>
> why is $extracted_string used here?
>
>

Right, it's always empty. I'm sending a v2.

Regards,
-- 
Matteo Croce
per aspera ad upstream