checkpatch: add warning on BUG/BUG_ON use

Using BUG/BUG_ON crashes the kernel and is just unfriendly.

Enable code that emits a warning on BUG/BUG_ON use.

Make the code emit the message at WARNING level when scanning a patch and
at CHECK level when scanning files so that script users don't feel an
obligation to fix code that might be above their pay grade.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 6 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 984a82e6b188..1629e3513f0d 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3448,13 +3448,15 @@ sub process {
                         }
                 }
 
-# # no BUG() or BUG_ON()
-#               if ($line =~ /\b(BUG|BUG_ON)\b/) {
-#                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
-#                       print "$herecurr";
-#                       $clean = 0;
-#               }
+# avoid BUG() or BUG_ON()
+                if ($line =~ /\b(?:BUG|BUG_ON)\b/) {
+                        my $msg_type = \&WARN;
+                        $msg_type = \&CHK if ($file);
+                        &{$msg_type}("AVOID_BUG",
+                                     "Avoid crashing the kernel - try using WARN_ON & recovery code rather than BUG() or BUG_ON()\n" . $herecurr);
+                }
 
+# avoid LINUX_VERSION_CODE
                 if ($line =~ /\bLINUX_VERSION_CODE\b/) {
                         WARN("LINUX_VERSION_CODE",
                              "LINUX_VERSION_CODE should be avoided, code should be for the version to which it is merged\n" . $herecurr);