checkpatch: warn on logging functions with KERN_<LEVEL>

Warn on probable misuses of logging functions with KERN_<LEVEL>
like pr_err(KERN_ERR "foo\n");

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 52a223e..374abf4 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4447,6 +4447,17 @@ sub process {
                        }
                }
 
+# check for logging functions with KERN_<LEVEL>
+               if ($line !~ /printk\s*\(/ &&
+                   $line =~ /\b$logFunctions\s*\(.*\b(KERN_[A-Z]+)\b/) {
+                       my $level = $1;
+                       if (WARN("UNNECESSARY_KERN_LEVEL",
+                                "Possible unnecessary $level\n" . $herecurr) &&
+                           $fix) {
+                               $fixed[$fixlinenr] =~ s/\s*$level\s*//;
+                       }
+               }
+
 # check for bad placement of section $InitAttribute (e.g.: __initdata)
                if ($line =~ /(\b$InitAttribute\b)/) {
                        my $attr = $1;