[PATCH] scripts/checkpatch: emit a warning if an imported file is touched

[Stefano Garzarella <sgarzare@redhat.com>]

If a file imported from Linux is touched, emit a warning and suggest
using scripts/update-linux-headers.sh

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
 scripts/checkpatch.pl | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ff373a7083..b0e8266fa2 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1374,6 +1374,7 @@ sub process {
 	my $in_header_lines = $file ? 0 : 1;
 	my $in_commit_log = 0;		#Scanning lines before patch
 	my $reported_maintainer_file = 0;
+	my $reported_imported_file = 0;
 	my $non_utf8_charset = 0;
 
 	our @report = ();
@@ -1673,8 +1674,17 @@ sub process {
 # ignore non-hunk lines and lines being removed
 		next if (!$hunk_line || $line =~ /^-/);
 
-# ignore files that are being periodically imported from Linux
-		next if ($realfile =~ /^(linux-headers|include\/standard-headers)\//);
+# ignore files that are being periodically imported from Linux and emit a warning
+		if ($realfile =~ /^(linux-headers|include\/standard-headers)\//) {
+			if (!$reported_imported_file) {
+				$reported_imported_file = 1;
+				WARN("added, moved or deleted file(s) " .
+				     "imported from Linux, are you using " .
+				     "scripts/update-linux-headers.sh?\n" .
+				     $herecurr);
+			}
+			next;
+		}
 
 #trailing whitespace
 		if ($line =~ /^\+.*\015/) {
-- 
2.45.2