From fc387a0704cc86cf47de0e64236577af3e148ec2 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Onur=20=C3=96zkan?= <work@onurozkan.dev>
Date: Wed, 17 Sep 2025 20:37:24 +0300
Subject: [PATCH] checkpatch: detect unhandled placeholders in cover letters
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Add a new check PLACEHOLDER_USE to detect unhandled placeholders.  This
prevents sending patch series with incomplete patches (mostly in cover
letters) containing auto generated subject or blurb lines.

These placeholders can be seen on mailing lists.  With this change,
checkpatch will emit an error when such text is found.

Link: https://lkml.kernel.org/r/20250917173725.22547-2-work@onurozkan.dev
Signed-off-by: Onur Özkan <work@onurozkan.dev>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 scripts/checkpatch.pl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 92669904eecc7..6729f18e56543 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3345,6 +3345,13 @@ sub process {
 			}
 		}
 
+# Check for auto-generated unhandled placeholder text (mostly for cover letters)
+		if (($in_commit_log || $in_header_lines) &&
+		    $rawline =~ /(?:SUBJECT|BLURB) HERE/) {
+			ERROR("PLACEHOLDER_USE",
+			      "Placeholder text detected\n" . $herecurr);
+		}
+
 # Check for git id commit length and improperly formed commit descriptions
 # A correctly formed commit description is:
 #    commit <SHA-1 hash length 12+ chars> ("Complete commit subject")
-- 
2.47.3