checkpatch.pl: update from Linux kernel v5.4-rc3

Update from upstream.

Just minor changes like checking that the author has also done a sign-off.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

1 files changed, 333 insertions, 113 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 373094e59ef..6fcc66afb08 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1,9 +1,11 @@
 #!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+#
 # (c) 2001, Dave Jones. (the file handling bit)
 # (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
 # (c) 2007,2008, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite)
 # (c) 2008-2010 Andy Whitcroft <apw@canonical.com>
-# Licensed under the terms of the GNU GPL License version 2
+# (c) 2010-2018 Joe Perches <joe@perches.com>
 
 use strict;
 use warnings;
@@ -11,6 +13,7 @@ use POSIX;
 use File::Basename;
 use Cwd 'abs_path';
 use Term::ANSIColor qw(:constants);
+use Encode qw(decode encode);
 
 my $P = $0;
 my $D = dirname(abs_path($P));
@@ -58,7 +61,9 @@ my $codespellfile = "/usr/share/codespell/dictionary.txt";
 my $conststructsfile = "$D/const_structs.checkpatch";
 my $typedefsfile = "";
 my $color = "auto";
-my $allow_c99_comments = 1;
+my $allow_c99_comments = 1; # Can be overridden by --ignore C99_COMMENT_TOLERANCE
+# git output parsing needs US English output, so first set backtick child process LANGUAGE
+my $git_command ='export LANGUAGE=en_US.UTF-8; git';
 
 sub help {
 	my ($exitcode) = @_;
@@ -238,11 +243,11 @@ $check_orig = $check;
 
 my $exit = 0;
 
+my $perl_version_ok = 1;
 if ($^V && $^V lt $minimum_perl_version) {
+	$perl_version_ok = 0;
 	printf "$P: requires at least perl version %vd\n", $minimum_perl_version;
-	if (!$ignore_perl_version) {
-		exit(1);
-	}
+	exit(1) if (!$ignore_perl_version);
 }
 
 #if no filenames are given, push '-' to read patch from stdin
@@ -344,9 +349,10 @@ our $Sparse	= qr{
 			__force|
 			__iomem|
 			__must_check|
-			__init_refok|
 			__kprobes|
 			__ref|
+			__refconst|
+			__refdata|
 			__rcu|
 			__private
 		}x;
@@ -376,6 +382,7 @@ our $Attribute	= qr{
 			__noclone|
 			__deprecated|
 			__read_mostly|
+			__ro_after_init|
 			__kprobes|
 			$InitAttribute|
 			____cacheline_aligned|
@@ -461,8 +468,19 @@ our $logFunctions = qr{(?x:
 	seq_vprintf|seq_printf|seq_puts
 )};
 
+our $allocFunctions = qr{(?x:
+	(?:(?:devm_)?
+		(?:kv|k|v)[czm]alloc(?:_node|_array)? |
+		kstrdup(?:_const)? |
+		kmemdup(?:_nul)?) |
+	(?:\w+)?alloc_skb(?:ip_align)? |
+				# dev_alloc_skb/netdev_alloc_skb, et al
+	dma_alloc_coherent
+)};
+
 our $signature_tags = qr{(?xi:
 	Signed-off-by:|
+	Co-developed-by:|
 	Acked-by:|
 	Tested-by:|
 	Reviewed-by:|
@@ -568,6 +586,27 @@ foreach my $entry (@mode_permission_funcs) {
 }
 $mode_perms_search = "(?:${mode_perms_search})";
 
+our %deprecated_apis = (
+	"synchronize_rcu_bh"			=> "synchronize_rcu",
+	"synchronize_rcu_bh_expedited"		=> "synchronize_rcu_expedited",
+	"call_rcu_bh"				=> "call_rcu",
+	"rcu_barrier_bh"			=> "rcu_barrier",
+	"synchronize_sched"			=> "synchronize_rcu",
+	"synchronize_sched_expedited"		=> "synchronize_rcu_expedited",
+	"call_rcu_sched"			=> "call_rcu",
+	"rcu_barrier_sched"			=> "rcu_barrier",
+	"get_state_synchronize_sched"		=> "get_state_synchronize_rcu",
+	"cond_synchronize_sched"		=> "cond_synchronize_rcu",
+);
+
+#Create a search pattern for all these strings to speed up a loop below
+our $deprecated_apis_search = "";
+foreach my $entry (keys %deprecated_apis) {
+	$deprecated_apis_search .= '|' if ($deprecated_apis_search ne "");
+	$deprecated_apis_search .= $entry;
+}
+$deprecated_apis_search = "(?:${deprecated_apis_search})";
+
 our $mode_perms_world_writable = qr{
 	S_IWUGO		|
 	S_IWOTH		|
@@ -845,6 +884,17 @@ sub is_maintained_obsolete {
 	return $status =~ /obsolete/i;
 }
 
+sub is_SPDX_License_valid {
+	my ($license) = @_;
+
+	return 1 if (!$tree || which("python") eq "" || !(-e "$root/scripts/spdxcheck.py") || !(-e "$root/.git"));
+
+	my $root_path = abs_path($root);
+	my $status = `cd "$root_path"; echo "$license" | python scripts/spdxcheck.py -`;
+	return 0 if ($status ne "");
+	return 1;
+}
+
 my $camelcase_seeded = 0;
 sub seed_camelcase_includes {
 	return if ($camelcase_seeded);
@@ -856,7 +906,7 @@ sub seed_camelcase_includes {
 	$camelcase_seeded = 1;
 
 	if (-e ".git") {
-		my $git_last_include_commit = `git log --no-merges --pretty=format:"%h%n" -1 -- include`;
+		my $git_last_include_commit = `${git_command} log --no-merges --pretty=format:"%h%n" -1 -- include`;
 		chomp $git_last_include_commit;
 		$camelcase_cache = ".checkpatch-camelcase.git.$git_last_include_commit";
 	} else {
@@ -884,7 +934,7 @@ sub seed_camelcase_includes {
 	}
 
 	if (-e ".git") {
-		$files = `git ls-files "include/*.h"`;
+		$files = `${git_command} ls-files "include/*.h"`;
 		@include_files = split('\n', $files);
 	}
 
@@ -908,13 +958,13 @@ sub git_commit_info {
 
 	return ($id, $desc) if ((which("git") eq "") || !(-e ".git"));
 
-	my $output = `git log --no-color --format='%H %s' -1 $commit 2>&1`;
+	my $output = `${git_command} log --no-color --format='%H %s' -1 $commit 2>&1`;
 	$output =~ s/^\s*//gm;
 	my @lines = split("\n", $output);
 
 	return ($id, $desc) if ($#lines < 0);
 
-	if ($lines[0] =~ /^error: short SHA1 $commit is ambiguous\./) {
+	if ($lines[0] =~ /^error: short SHA1 $commit is ambiguous/) {
 # Maybe one day convert this block of bash into something that returns
 # all matching commit ids, but it's very slow...
 #
@@ -958,7 +1008,7 @@ if ($git) {
 		} else {
 			$git_range = "-1 $commit_expr";
 		}
-		my $lines = `git log --no-color --no-merges --pretty=format:'%H %s' $git_range`;
+		my $lines = `${git_command} log --no-color --no-merges --pretty=format:'%H %s' $git_range`;
 		foreach my $line (split(/\n/, $lines)) {
 			$line =~ /^([0-9a-fA-F]{40,40}) (.*)$/;
 			next if (!defined($1) || !defined($2));
@@ -973,6 +1023,7 @@ if ($git) {
 }
 
 my $vname;
+$allow_c99_comments = !defined $ignore_type{"C99_COMMENT_TOLERANCE"};
 for my $filename (@ARGV) {
 	my $FILE;
 	if ($git) {
@@ -1024,11 +1075,11 @@ if (!$quiet) {
 	hash_show_words(\%use_type, "Used");
 	hash_show_words(\%ignore_type, "Ignored");
 
-	if ($^V lt 5.10.0) {
+	if (!$perl_version_ok) {
 		print << "EOM"
 
 NOTE: perl $^V is not modern enough to detect all possible issues.
-      An upgrade to at least perl v5.10.0 is suggested.
+      An upgrade to at least perl $minimum_perl_version is suggested.
 EOM
 	}
 	if ($exit) {
@@ -2233,10 +2284,14 @@ sub process {
 
 	our $clean = 1;
 	my $signoff = 0;
+	my $author = '';
+	my $authorsignoff = 0;
 	my $is_patch = 0;
+	my $is_binding_patch = -1;
 	my $in_header_lines = $file ? 0 : 1;
 	my $in_commit_log = 0;		#Scanning lines before patch
 	my $has_commit_log = 0;		#Encountered lines before patch
+	my $commit_log_lines = 0;	#Number of commit log lines
 	my $commit_log_possible_stack_dump = 0;
 	my $commit_log_long_line = 0;
 	my $commit_log_has_diff = 0;
@@ -2375,6 +2430,14 @@ sub process {
 
 		my $rawline = $rawlines[$linenr - 1];
 
+# check if it's a mode change, rename or start of a patch
+		if (!$in_commit_log &&
+		    ($line =~ /^ mode change [0-7]+ => [0-7]+ \S+\s*$/ ||
+		    ($line =~ /^rename (?:from|to) \S+\s*$/ ||
+		     $line =~ /^diff --git a\/[\w\/\.\_\-]+ b\/\S+\s*$/))) {
+			$is_patch = 1;
+		}
+
 #extract the line range in the file after the patch is applied
 		if (!$in_commit_log &&
 		    $line =~ /^\@\@ -\d+(?:,\d+)? \+(\d+)(,(\d+))? \@\@(.*)/) {
@@ -2475,6 +2538,19 @@ sub process {
 				$check = $check_orig;
 			}
 			$checklicenseline = 1;
+
+			if ($realfile !~ /^MAINTAINERS/) {
+				my $last_binding_patch = $is_binding_patch;
+
+				$is_binding_patch = () = $realfile =~ m@^(?:Documentation/devicetree/|include/dt-bindings/)@;
+
+				if (($last_binding_patch != -1) &&
+				    ($last_binding_patch ^ $is_binding_patch)) {
+					WARN("DT_SPLIT_BINDING_PATCH",
+					     "DT binding docs and includes should be a separate patch. See: Documentation/devicetree/bindings/submitting-patches.txt\n");
+				}
+			}
+
 			next;
 		}
 
@@ -2486,6 +2562,18 @@ sub process {
 
 		$cnt_lines++ if ($realcnt != 0);
 
+# Verify the existence of a commit log if appropriate
+# 2 is used because a $signature is counted in $commit_log_lines
+		if ($in_commit_log) {
+			if ($line !~ /^\s*$/) {
+				$commit_log_lines++;	#could be a $signature
+			}
+		} elsif ($has_commit_log && $commit_log_lines < 2) {
+			WARN("COMMIT_MESSAGE",
+			     "Missing commit description - Add an appropriate one\n");
+			$commit_log_lines = 2;	#warn only once
+		}
+
 # Check if the commit log has what seems like a diff which can confuse patch
 		if ($in_commit_log && !$commit_log_has_diff &&
 		    (($line =~ m@^\s+diff\b.*a/[\w/]+@ &&
@@ -2507,10 +2595,24 @@ sub process {
 			}
 		}
 
+# Check the patch for a From:
+		if (decode("MIME-Header", $line) =~ /^From:\s*(.*)/) {
+			$author = $1;
+			$author = encode("utf8", $author) if ($line =~ /=\?utf-8\?/i);
+			$author =~ s/"//g;
+		}
+
 # Check the patch for a signoff:
 		if ($line =~ /^\s*signed-off-by:/i) {
 			$signoff++;
 			$in_commit_log = 0;
+			if ($author ne '') {
+				my $l = $line;
+				$l =~ s/"//g;
+				if ($l =~ /^\s*signed-off-by:\s*\Q$author\E/i) {
+				    $authorsignoff = 1;
+				}
+			}
 		}
 
 # Check if MAINTAINERS is being updated.  If so, there's probably no need to
@@ -2587,6 +2689,24 @@ sub process {
 			} else {
 				$signatures{$sig_nospace} = 1;
 			}
+
+# Check Co-developed-by: immediately followed by Signed-off-by: with same name and email
+			if ($sign_off =~ /^co-developed-by:$/i) {
+				if ($email eq $author) {
+					WARN("BAD_SIGN_OFF",
+					      "Co-developed-by: should not be used to attribute nominal patch author '$author'\n" . "$here\n" . $rawline);
+				}
+				if (!defined $lines[$linenr]) {
+					WARN("BAD_SIGN_OFF",
+                                             "Co-developed-by: must be immediately followed by Signed-off-by:\n" . "$here\n" . $rawline);
+				} elsif ($rawlines[$linenr] !~ /^\s*signed-off-by:\s*(.*)/i) {
+					WARN("BAD_SIGN_OFF",
+					     "Co-developed-by: must be immediately followed by Signed-off-by:\n" . "$here\n" . $rawline . "\n" .$rawlines[$linenr]);
+				} elsif ($1 ne $email) {
+					WARN("BAD_SIGN_OFF",
+					     "Co-developed-by and Signed-off-by: name/email do not match \n" . "$here\n" . $rawline . "\n" .$rawlines[$linenr]);
+				}
+			}
 		}
 
 # Check email subject for common tools that don't need to be mentioned
@@ -2596,12 +2716,6 @@ sub process {
 			     "A patch subject line should describe the change not the tool that found it\n" . $herecurr);
 		}
 
-# Check for old stable address
-		if ($line =~ /^\s*cc:\s*.*<?\bstable\@kernel\.org\b>?.*$/i) {
-			ERROR("STABLE_ADDRESS",
-			      "The 'stable' address should be 'stable\@vger.kernel.org'\n" . $herecurr);
-		}
-
 # Check for unwanted Gerrit info
 		if ($in_commit_log && $line =~ /^\s*change-id:/i) {
 			ERROR("GERRIT_CHANGE_ID",
@@ -2613,8 +2727,10 @@ sub process {
 		    ($line =~ /^\s*(?:WARNING:|BUG:)/ ||
 		     $line =~ /^\s*\[\s*\d+\.\d{6,6}\s*\]/ ||
 					# timestamp
-		     $line =~ /^\s*\[\<[0-9a-fA-F]{8,}\>\]/)) {
-					# stack dump address
+		     $line =~ /^\s*\[\<[0-9a-fA-F]{8,}\>\]/) ||
+		     $line =~ /^(?:\s+\w+:\s+[0-9a-fA-F]+){3,3}/ ||
+		     $line =~ /^\s*\#\d+\s*\[[0-9a-fA-F]+\]\s*\w+ at [0-9a-fA-F]+/) {
+					# stack dump address styles
 			$commit_log_possible_stack_dump = 1;
 		}
 
@@ -2786,6 +2902,17 @@ sub process {
 			}
 		}
 
+# check for invalid commit id
+		if ($in_commit_log && $line =~ /(^fixes:|\bcommit)\s+([0-9a-f]{6,40})\b/i) {
+			my $id;
+			my $description;
+			($id, $description) = git_commit_info($2, undef, undef);
+			if (!defined($id)) {
+				WARN("UNKNOWN_COMMIT_ID",
+				     "Unknown commit id '$2', maybe rebased or not pulled?\n" . $herecurr);
+			}
+		}
+
 # ignore non-hunk lines and lines being removed
 		next if (!$hunk_line || $line =~ /^-/);
 
@@ -2915,7 +3042,7 @@ sub process {
 			my @compats = $rawline =~ /\"([a-zA-Z0-9\-\,\.\+_]+)\"/g;
 
 			my $dt_path = $root . "/Documentation/devicetree/bindings/";
-			my $vp_file = $dt_path . "vendor-prefixes.txt";
+			my $vp_file = $dt_path . "vendor-prefixes.yaml";
 
 			foreach my $compat (@compats) {
 				my $compat2 = $compat;
@@ -2930,7 +3057,7 @@ sub process {
 
 				next if $compat !~ /^([a-zA-Z0-9\-]+)\,/;
 				my $vendor = $1;
-				`grep -Eq "^$vendor\\b" $vp_file`;
+				`grep -Eq "\\"\\^\Q$vendor\E,\\.\\*\\":" $vp_file`;
 				if ( $? >> 8 ) {
 					WARN("UNDOCUMENTED_DT_STRING",
 					     "DT compatible string vendor \"$vendor\" appears un-documented -- check $vp_file\n" . $herecurr);
@@ -2954,10 +3081,24 @@ sub process {
 					$comment = '..';
 				}
 
+# check SPDX comment style for .[chsS] files
+				if ($realfile =~ /\.[chsS]$/ &&
+				    $rawline =~ /SPDX-License-Identifier:/ &&
+				    $rawline !~ m@^\+\s*\Q$comment\E\s*@) {
+					WARN("SPDX_LICENSE_TAG",
+					     "Improper SPDX comment style for '$realfile', please use '$comment' instead\n" . $herecurr);
+				}
+
 				if ($comment !~ /^$/ &&
-				    $rawline !~ /^\+\Q$comment\E SPDX-License-Identifier: /) {
+				    $rawline !~ m@^\+\Q$comment\E SPDX-License-Identifier: @) {
 					WARN("SPDX_LICENSE_TAG",
 					     "Missing or malformed SPDX-License-Identifier tag in line $checklicenseline\n" . $herecurr);
+				} elsif ($rawline =~ /(SPDX-License-Identifier: .*)/) {
+					my $spdx_license = $1;
+					if (!is_SPDX_License_valid($spdx_license)) {
+						WARN("SPDX_LICENSE_TAG",
+						     "'$spdx_license' is not supported in LICENSES/...\n" . $herecurr);
+					}
 				}
 			}
 		}
@@ -2965,6 +3106,14 @@ sub process {
 # check we are in a valid source file if not then ignore this hunk
 		next if ($realfile !~ /\.(h|c|s|S|sh|dtsi|dts)$/);
 
+# check for using SPDX-License-Identifier on the wrong line number
+		if ($realline != $checklicenseline &&
+		    $rawline =~ /\bSPDX-License-Identifier:/ &&
+		    substr($line, @-, @+ - @-) eq "$;" x (@+ - @-)) {
+			WARN("SPDX_LICENSE_TAG",
+			     "Misplaced SPDX-License-Identifier tag - use line $checklicenseline instead\n" . $herecurr);
+		}
+
 # line length limit (with some exclusions)
 #
 # There are a few types of lines that may extend beyond $max_line_length:
@@ -3062,6 +3211,12 @@ sub process {
 			}
 		}
 
+# check for assignments on the start of a line
+		if ($sline =~ /^\+\s+($Assignment)[^=]/) {
+			CHK("ASSIGNMENT_CONTINUATIONS",
+			    "Assignment operator '$1' should be on the previous line\n" . $hereprev);
+		}
+
 # check for && or || at the start of a line
 		if ($rawline =~ /^\+\s*(&&|\|\|)/) {
 			CHK("LOGICAL_CONTINUATIONS",
@@ -3069,7 +3224,7 @@ sub process {
 		}
 
 # check indentation starts on a tab stop
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $sline =~ /^\+\t+( +)(?:$c90_Keywords\b|\{\s*$|\}\s*(?:else\b|while\b|\s*$)|$Declare\s*$Ident\s*[;=])/) {
 			my $indent = length($1);
 			if ($indent % 8) {
@@ -3082,7 +3237,7 @@ sub process {
 		}
 
 # check multi-line statement indentation matches previous line
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $prevline =~ /^\+([ \t]*)((?:$c90_Keywords(?:\s+if)\s*)|(?:$Declare\s*)?(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*|(?:\*\s*)*$Lval\s*=\s*$Ident\s*)\(.*(\&\&|\|\||,)\s*$/) {
 			$prevline =~ /^\+(\t*)(.*)$/;
 			my $oldindent = $1;
@@ -3239,7 +3394,7 @@ sub process {
 			# known declaration macros
 		      $sline =~ /^\+\s+$declaration_macros/ ||
 			# start of struct or union or enum
-		      $sline =~ /^\+\s+(?:union|struct|enum|typedef)\b/ ||
+		      $sline =~ /^\+\s+(?:static\s+)?(?:const\s+)?(?:union|struct|enum|typedef)\b/ ||
 			# start or end of block or continuation of declaration
 		      $sline =~ /^\+\s+(?:$|[\{\}\.\#\"\?\:\(\[])/ ||
 			# bitfield continuation
@@ -3771,19 +3926,48 @@ sub process {
 			     "type '$tmp' should be specified in [[un]signed] [short|int|long|long long] order\n" . $herecurr);
 		}
 
+# check for unnecessary <signed> int declarations of short/long/long long
+		while ($sline =~ m{\b($TypeMisordered(\s*\*)*|$C90_int_types)\b}g) {
+			my $type = trim($1);
+			next if ($type !~ /\bint\b/);
+			next if ($type !~ /\b(?:short|long\s+long|long)\b/);
+			my $new_type = $type;
+			$new_type =~ s/\b\s*int\s*\b/ /;
+			$new_type =~ s/\b\s*(?:un)?signed\b\s*/ /;
+			$new_type =~ s/^const\s+//;
+			$new_type = "unsigned $new_type" if ($type =~ /\bunsigned\b/);
+			$new_type = "const $new_type" if ($type =~ /^const\b/);
+			$new_type =~ s/\s+/ /g;
+			$new_type = trim($new_type);
+			if (WARN("UNNECESSARY_INT",
+				 "Prefer '$new_type' over '$type' as the int is unnecessary\n" . $herecurr) &&
+			    $fix) {
+				$fixed[$fixlinenr] =~ s/\b\Q$type\E\b/$new_type/;
+			}
+		}
+
 # check for static const char * arrays.
 		if ($line =~ /\bstatic\s+const\s+char\s*\*\s*(\w+)\s*\[\s*\]\s*=\s*/) {
 			WARN("STATIC_CONST_CHAR_ARRAY",
 			     "static const char * array should probably be static const char * const\n" .
 				$herecurr);
-               }
+		}
+
+# check for initialized const char arrays that should be static const
+		if ($line =~ /^\+\s*const\s+(char|unsigned\s+char|_*u8|(?:[us]_)?int8_t)\s+\w+\s*\[\s*(?:\w+\s*)?\]\s*=\s*"/) {
+			if (WARN("STATIC_CONST_CHAR_ARRAY",
+				 "const array should probably be static const\n" . $herecurr) &&
+			    $fix) {
+				$fixed[$fixlinenr] =~ s/(^.\s*)const\b/${1}static const/;
+			}
+		}
 
 # check for static char foo[] = "bar" declarations.
 		if ($line =~ /\bstatic\s+char\s+(\w+)\s*\[\s*\]\s*=\s*"/) {
 			WARN("STATIC_CONST_CHAR_ARRAY",
 			     "static char array declaration should probably be static const char\n" .
 				$herecurr);
-               }
+		}
 
 # check for const <foo> const where <foo> is not a pointer or array type
 		if ($sline =~ /\bconst\s+($BasicType)\s+const\b/) {
@@ -3957,7 +4141,7 @@ sub process {
 
 # function brace can't be on same line, except for #defines of do while,
 # or if closed on same line
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $sline =~ /$Type\s*$Ident\s*$balanced_parens\s*\{/ &&
 		    $sline !~ /\#\s*define\b.*do\s*\{/ &&
 		    $sline !~ /}/) {
@@ -4083,7 +4267,7 @@ sub process {
 			my ($where, $prefix) = ($-[1], $1);
 			if ($prefix !~ /$Type\s+$/ &&
 			    ($where != 0 || $prefix !~ /^.\s+$/) &&
-			    $prefix !~ /[{,]\s+$/) {
+			    $prefix !~ /[{,:]\s+$/) {
 				if (ERROR("BRACKET_SPACE",
 					  "space prohibited before open square bracket '['\n" . $herecurr) &&
 				    $fix) {
@@ -4473,11 +4657,11 @@ sub process {
 
 #need space before brace following if, while, etc
 		if (($line =~ /\(.*\)\{/ && $line !~ /\($Type\)\{/) ||
-		    $line =~ /do\{/) {
+		    $line =~ /\b(?:else|do)\{/) {
 			if (ERROR("SPACING",
 				  "space required before the open brace '{'\n" . $herecurr) &&
 			    $fix) {
-				$fixed[$fixlinenr] =~ s/^(\+.*(?:do|\)))\{/$1 {/;
+				$fixed[$fixlinenr] =~ s/^(\+.*(?:do|else|\)))\{/$1 {/;
 			}
 		}
 
@@ -4491,7 +4675,7 @@ sub process {
 
 # closing brace should have a space following it when it has anything
 # on the line
-		if ($line =~ /}(?!(?:,|;|\)))\S/) {
+		if ($line =~ /}(?!(?:,|;|\)|\}))\S/) {
 			if (ERROR("SPACING",
 				  "space required after that close brace '}'\n" . $herecurr) &&
 			    $fix) {
@@ -4568,7 +4752,7 @@ sub process {
 # check for unnecessary parentheses around comparisons in if uses
 # when !drivers/staging or command-line uses --strict
 		if (($realfile !~ m@^(?:drivers/staging/)@ || $check_orig) &&
-		    $^V && $^V ge 5.10.0 && defined($stat) &&
+		    $perl_version_ok && defined($stat) &&
 		    $stat =~ /(^.\s*if\s*($balanced_parens))/) {
 			my $if_stat = $1;
 			my $test = substr($2, 1, -1);
@@ -4605,7 +4789,7 @@ sub process {
 # return is not a function
 		if (defined($stat) && $stat =~ /^.\s*return(\s*)\(/s) {
 			my $spacing = $1;
-			if ($^V && $^V ge 5.10.0 &&
+			if ($perl_version_ok &&
 			    $stat =~ /^.\s*return\s*($balanced_parens)\s*;\s*$/) {
 				my $value = $1;
 				$value = deparenthesize($value);
@@ -4632,7 +4816,7 @@ sub process {
                }
 
 # if statements using unnecessary parentheses - ie: if ((foo == bar))
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $line =~ /\bif\s*((?:\(\s*){2,})/) {
 			my $openparens = $1;
 			my $count = $openparens =~ tr@\(@\(@;
@@ -4649,7 +4833,7 @@ sub process {
 #	avoid cases like "foo + BAR < baz"
 #	only fix matches surrounded by parentheses to avoid incorrect
 #	conversions like "FOO < baz() + 5" being "misfixed" to "baz() > FOO + 5"
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $line =~ /^\+(.*)\b($Constant|[A-Z_][A-Z0-9_]*)\s*($Compare)\s*($LvalOrFunc)/) {
 			my $lead = $1;
 			my $const = $2;
@@ -4841,17 +5025,6 @@ sub process {
 		while ($line =~ m{($Constant|$Lval)}g) {
 			my $var = $1;
 
-#gcc binary extension
-			if ($var =~ /^$Binary$/) {
-				if (WARN("GCC_BINARY_CONSTANT",
-					 "Avoid gcc v4.3+ binary constant extension: <$var>\n" . $herecurr) &&
-				    $fix) {
-					my $hexval = sprintf("0x%x", oct($var));
-					$fixed[$fixlinenr] =~
-					    s/\b$var\b/$hexval/;
-				}
-			}
-
 #CamelCase
 			if ($var !~ /^$Constant$/ &&
 			    $var =~ /[A-Z][a-z]|[a-z][A-Z]/ &&
@@ -4939,6 +5112,7 @@ sub process {
 			if (defined $define_args && $define_args ne "") {
 				$define_args = substr($define_args, 1, length($define_args) - 2);
 				$define_args =~ s/\s*//g;
+				$define_args =~ s/\\\+?//g;
 				@def_args = split(",", $define_args);
 			}
 
@@ -5032,10 +5206,10 @@ sub process {
 			        next if ($arg =~ /\.\.\./);
 			        next if ($arg =~ /^type$/i);
 				my $tmp_stmt = $define_stmt;
-				$tmp_stmt =~ s/\b(typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
+				$tmp_stmt =~ s/\b(sizeof|typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
 				$tmp_stmt =~ s/\#+\s*$arg\b//g;
 				$tmp_stmt =~ s/\b$arg\s*\#\#//g;
-				my $use_cnt = $tmp_stmt =~ s/\b$arg\b//g;
+				my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
 				if ($use_cnt > 1) {
 					CHK("MACRO_ARG_REUSE",
 					    "Macro argument reuse '$arg' - possible side-effects?\n" . "$herectx");
@@ -5074,7 +5248,7 @@ sub process {
 # do {} while (0) macro tests:
 # single-statement macros do not need to be enclosed in do while (0) loop,
 # macro should not end with a semicolon
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $realfile !~ m@/vmlinux.lds.h$@ &&
 		    $line =~ /^.\s*\#\s*define\s+$Ident(\()?/) {
 			my $ln = $linenr;
@@ -5115,16 +5289,6 @@ sub process {
 			}
 		}
 
-# make sure symbols are always wrapped with VMLINUX_SYMBOL() ...
-# all assignments may have only one of the following with an assignment:
-#	.
-#	ALIGN(...)
-#	VMLINUX_SYMBOL(...)
-		if ($realfile eq 'vmlinux.lds.h' && $line =~ /(?:(?:^|\s)$Ident\s*=|=\s*$Ident(?:\s|$))/) {
-			WARN("MISSING_VMLINUX_SYMBOL",
-			     "vmlinux.lds.h needs VMLINUX_SYMBOL() around C-visible symbols\n" . $herecurr);
-		}
-
 # check for redundant bracing round if etc
 		if ($line =~ /(^.*)\bif\b/ && $1 !~ /else\s*$/) {
 			my ($level, $endln, @chunks) =
@@ -5330,15 +5494,28 @@ sub process {
 		}
 
 # concatenated string without spaces between elements
-		if ($line =~ /$String[A-Z_]/ || $line =~ /[A-Za-z0-9_]$String/) {
-			CHK("CONCATENATED_STRING",
-			    "Concatenated strings should use spaces between elements\n" . $herecurr);
+		if ($line =~ /$String[A-Za-z0-9_]/ || $line =~ /[A-Za-z0-9_]$String/) {
+			if (CHK("CONCATENATED_STRING",
+				"Concatenated strings should use spaces between elements\n" . $herecurr) &&
+			    $fix) {
+				while ($line =~ /($String)/g) {
+					my $extracted_string = substr($rawline, $-[0], $+[0] - $-[0]);
+					$fixed[$fixlinenr] =~ s/\Q$extracted_string\E([A-Za-z0-9_])/$extracted_string $1/;
+					$fixed[$fixlinenr] =~ s/([A-Za-z0-9_])\Q$extracted_string\E/$1 $extracted_string/;
+				}
+			}
 		}
 
 # uncoalesced string fragments
 		if ($line =~ /$String\s*"/) {
-			WARN("STRING_FRAGMENTS",
-			     "Consecutive strings are generally better as a single string\n" . $herecurr);
+			if (WARN("STRING_FRAGMENTS",
+				 "Consecutive strings are generally better as a single string\n" . $herecurr) &&
+			    $fix) {
+				while ($line =~ /($String)(?=\s*")/g) {
+					my $extracted_string = substr($rawline, $-[0], $+[0] - $-[0]);
+					$fixed[$fixlinenr] =~ s/\Q$extracted_string\E\s*"/substr($extracted_string, 0, -1)/e;
+				}
+			}
 		}
 
 # check for non-standard and hex prefixed decimal printf formats
@@ -5374,9 +5551,14 @@ sub process {
 
 # warn about #if 0
 		if ($line =~ /^.\s*\#\s*if\s+0\b/) {
-			CHK("REDUNDANT_CODE",
-			    "if this code is redundant consider removing it\n" .
-				$herecurr);
+			WARN("IF_0",
+			     "Consider removing the code enclosed by this #if 0 and its #endif\n" . $herecurr);
+		}
+
+# warn about #if 1
+		if ($line =~ /^.\s*\#\s*if\s+1\b/) {
+			WARN("IF_1",
+			     "Consider removing the #if 1 and its #endif\n" . $herecurr);
 		}
 
 # check for needless "if (<foo>) fn(<foo>)" uses
@@ -5423,7 +5605,8 @@ sub process {
 			my ($s, $c) = ctx_statement_block($linenr - 3, $realcnt, 0);
 #			print("line: <$line>\nprevline: <$prevline>\ns: <$s>\nc: <$c>\n\n\n");
 
-			if ($s =~ /(?:^|\n)[ \+]\s*(?:$Type\s*)?\Q$testval\E\s*=\s*(?:\([^\)]*\)\s*)?\s*(?:devm_)?(?:[kv][czm]alloc(?:_node|_array)?\b|kstrdup|kmemdup|(?:dev_)?alloc_skb)/) {
+			if ($s =~ /(?:^|\n)[ \+]\s*(?:$Type\s*)?\Q$testval\E\s*=\s*(?:\([^\)]*\)\s*)?\s*$allocFunctions\s*\(/ &&
+			    $s !~ /\b__GFP_NOWARN\b/ ) {
 				WARN("OOM_MESSAGE",
 				     "Possible unnecessary 'out of memory' message\n" . $hereprev);
 			}
@@ -5447,7 +5630,7 @@ sub process {
 		}
 
 # check for mask then right shift without a parentheses
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $line =~ /$LvalOrFunc\s*\&\s*($LvalOrFunc)\s*>>/ &&
 		    $4 !~ /^\&/) { # $LvalOrFunc may be &foo, ignore if so
 			WARN("MASK_THEN_SHIFT",
@@ -5455,7 +5638,7 @@ sub process {
 		}
 
 # check for pointer comparisons to NULL
-		if ($^V && $^V ge 5.10.0) {
+		if ($perl_version_ok) {
 			while ($line =~ /\b$LvalOrFunc\s*(==|\!=)\s*NULL\b/g) {
 				my $val = $1;
 				my $equal = "!";
@@ -5544,7 +5727,7 @@ sub process {
 			# ignore udelay's < 10, however
 			if (! ($delay < 10) ) {
 				CHK("USLEEP_RANGE",
-				    "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $herecurr);
+				    "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.rst\n" . $herecurr);
 			}
 			if ($delay > 2000) {
 				WARN("LONG_UDELAY",
@@ -5556,7 +5739,7 @@ sub process {
 		if ($line =~ /\bmsleep\s*\((\d+)\);/) {
 			if ($1 < 20) {
 				WARN("MSLEEP",
-				     "msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.txt\n" . $herecurr);
+				     "msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.rst\n" . $herecurr);
 			}
 		}
 
@@ -5698,13 +5881,6 @@ sub process {
 			     "__packed is preferred over __attribute__((packed))\n" . $herecurr);
 		}
 
-# Check for new packed members, warn to use care
-		if ($realfile !~ m@\binclude/uapi/@ &&
-		    $line =~ /\b(__attribute__\s*\(\s*\(.*\bpacked|__packed)\b/) {
-			WARN("NEW_PACKED",
-			     "Adding new packed members is to be done with care\n" . $herecurr);
-		}
-
 # Check for __attribute__ aligned, prefer __aligned
 		if ($realfile !~ m@\binclude/uapi/@ &&
 		    $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) {
@@ -5712,6 +5888,18 @@ sub process {
 			     "__aligned(size) is preferred over __attribute__((aligned(size)))\n" . $herecurr);
 		}
 
+# Check for __attribute__ section, prefer __section
+		if ($realfile !~ m@\binclude/uapi/@ &&
+		    $line =~ /\b__attribute__\s*\(\s*\(.*_*section_*\s*\(\s*("[^"]*")/) {
+			my $old = substr($rawline, $-[1], $+[1] - $-[1]);
+			my $new = substr($old, 1, -1);
+			if (WARN("PREFER_SECTION",
+				 "__section($new) is preferred over __attribute__((section($old)))\n" . $herecurr) &&
+			    $fix) {
+				$fixed[$fixlinenr] =~ s/\b__attribute__\s*\(\s*\(\s*_*section_*\s*\(\s*\Q$old\E\s*\)\s*\)\s*\)/__section($new)/;
+			}
+		}
+
 # Check for __attribute__ format(printf, prefer __printf
 		if ($realfile !~ m@\binclude/uapi/@ &&
 		    $line =~ /\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf/) {
@@ -5734,7 +5922,7 @@ sub process {
 		}
 
 # Check for __attribute__ weak, or __weak declarations (may have link issues)
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ &&
 		    ($line =~ /\b__attribute__\s*\(\s*\(.*\bweak\b/ ||
 		     $line =~ /\b__weak\b/)) {
@@ -5816,25 +6004,25 @@ sub process {
 		}
 
 # check for vsprintf extension %p<foo> misuses
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s &&
 		    $1 !~ /^_*volatile_*$/) {
-			my $specifier;
-			my $extension;
-			my $bad_specifier = "";
 			my $stat_real;
 
 			my $lc = $stat =~ tr@\n@@;
 			$lc = $lc + $linenr;
 		        for (my $count = $linenr; $count <= $lc; $count++) {
+				my $specifier;
+				my $extension;
+				my $bad_specifier = "";
 				my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0));
 				$fmt =~ s/%%//g;
 
 				while ($fmt =~ /(\%[\*\d\.]*p(\w))/g) {
 					$specifier = $1;
 					$extension = $2;
-					if ($extension !~ /[SsBKRraEhMmIiUDdgVCbGNOx]/) {
+					if ($extension !~ /[SsBKRraEhMmIiUDdgVCbGNOxt]/) {
 						$bad_specifier = $specifier;
 						last;
 					}
@@ -5863,7 +6051,7 @@ sub process {
 		}
 
 # Check for misused memsets
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*$FuncArg\s*\)/) {
 
@@ -5881,7 +6069,7 @@ sub process {
 		}
 
 # Check for memcpy(foo, bar, ETH_ALEN) that could be ether_addr_copy(foo, bar)
-#		if ($^V && $^V ge 5.10.0 &&
+#		if ($perl_version_ok &&
 #		    defined $stat &&
 #		    $stat =~ /^\+(?:.*?)\bmemcpy\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
 #			if (WARN("PREFER_ETHER_ADDR_COPY",
@@ -5892,7 +6080,7 @@ sub process {
 #		}
 
 # Check for memcmp(foo, bar, ETH_ALEN) that could be ether_addr_equal*(foo, bar)
-#		if ($^V && $^V ge 5.10.0 &&
+#		if ($perl_version_ok &&
 #		    defined $stat &&
 #		    $stat =~ /^\+(?:.*?)\bmemcmp\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
 #			WARN("PREFER_ETHER_ADDR_EQUAL",
@@ -5901,7 +6089,7 @@ sub process {
 
 # check for memset(foo, 0x0, ETH_ALEN) that could be eth_zero_addr
 # check for memset(foo, 0xFF, ETH_ALEN) that could be eth_broadcast_addr
-#		if ($^V && $^V ge 5.10.0 &&
+#		if ($perl_version_ok &&
 #		    defined $stat &&
 #		    $stat =~ /^\+(?:.*?)\bmemset\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\,\s*ETH_ALEN\s*\)/) {
 #
@@ -5923,7 +6111,7 @@ sub process {
 #		}
 
 # typecasts on min/max could be min_t/max_t
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+(?:.*?)\b(min|max)\s*\(\s*$FuncArg\s*,\s*$FuncArg\s*\)/) {
 			if (defined $2 || defined $7) {
@@ -5947,23 +6135,23 @@ sub process {
 		}
 
 # check usleep_range arguments
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+(?:.*?)\busleep_range\s*\(\s*($FuncArg)\s*,\s*($FuncArg)\s*\)/) {
 			my $min = $1;
 			my $max = $7;
 			if ($min eq $max) {
 				WARN("USLEEP_RANGE",
-				     "usleep_range should not use min == max args; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
+				     "usleep_range should not use min == max args; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n");
 			} elsif ($min =~ /^\d+$/ && $max =~ /^\d+$/ &&
 				 $min > $max) {
 				WARN("USLEEP_RANGE",
-				     "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
+				     "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.rst\n" . "$here\n$stat\n");
 			}
 		}
 
 # check for naked sscanf
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $line =~ /\bsscanf\b/ &&
 		    ($stat !~ /$Ident\s*=\s*sscanf\s*$balanced_parens/ &&
@@ -5977,7 +6165,7 @@ sub process {
 		}
 
 # check for simple sscanf that should be kstrto<foo>
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $line =~ /\bsscanf\b/) {
 			my $lc = $stat =~ tr@\n@@;
@@ -6049,7 +6237,7 @@ sub process {
 		}
 
 # check for function definitions
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^.\s*(?:$Storage\s+)?$Type\s*($Ident)\s*$balanced_parens\s*{/s) {
 			$context_function = $1;
@@ -6081,22 +6269,22 @@ sub process {
 			}
 		}
 
-# check for pointless casting of kmalloc return
-		if ($line =~ /\*\s*\)\s*[kv][czm]alloc(_node){0,1}\b/) {
+# check for pointless casting of alloc functions
+		if ($line =~ /\*\s*\)\s*$allocFunctions\b/) {
 			WARN("UNNECESSARY_CASTS",
 			     "unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
 		}
 
 # alloc style
 # p = alloc(sizeof(struct foo), ...) should be p = alloc(sizeof(*p), ...)
-		if ($^V && $^V ge 5.10.0 &&
-		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*([kv][mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) {
+		if ($perl_version_ok &&
+		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*((?:kv|k|v)[mz]alloc(?:_node)?)\s*\(\s*(sizeof\s*\(\s*struct\s+$Lval\s*\))/) {
 			CHK("ALLOC_SIZEOF_STRUCT",
 			    "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);
 		}
 
 # check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+\s*($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) {
 			my $oldfunc = $3;
@@ -6125,8 +6313,9 @@ sub process {
 		}
 
 # check for krealloc arg reuse
-		if ($^V && $^V ge 5.10.0 &&
-		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
+		if ($perl_version_ok &&
+		    $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*($Lval)\s*,/ &&
+		    $1 eq $3) {
 			WARN("KREALLOC_ARG_REUSE",
 			     "Reusing the krealloc arg is almost always a bug\n" . $herecurr);
 		}
@@ -6194,7 +6383,7 @@ sub process {
 		}
 
 # check for switch/default statements without a break;
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /^\+[$;\s]*(?:case[$;\s]+\w+[$;\s]*:[$;\s]*|)*[$;\s]*\bdefault[$;\s]*:[$;\s]*;/g) {
 			my $cnt = statement_rawlines($stat);
@@ -6270,6 +6459,20 @@ sub process {
 			     "please use device_initcall() or more appropriate function instead of __initcall() (see include/linux/init.h)\n" . $herecurr);
 		}
 
+# check for spin_is_locked(), suggest lockdep instead
+		if ($line =~ /\bspin_is_locked\(/) {
+			WARN("USE_LOCKDEP",
+			     "Where possible, use lockdep_assert_held instead of assertions based on spin_is_locked\n" . $herecurr);
+		}
+
+# check for deprecated apis
+		if ($line =~ /\b($deprecated_apis_search)\b\s*\(/) {
+			my $deprecated_api = $1;
+			my $new_api = $deprecated_apis{$deprecated_api};
+			WARN("DEPRECATED_API",
+			     "Deprecated use of '$deprecated_api', prefer '$new_api' instead\n" . $herecurr);
+		}
+
 # check for various structs that are normally const (ops, kgdb, device_tree)
 # and avoid what seem like struct definitions 'struct foo {'
 		if ($line !~ /\bconst\b/ &&
@@ -6298,12 +6501,18 @@ sub process {
 		}
 
 # likely/unlikely comparisons similar to "(likely(foo) > 0)"
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    $line =~ /\b((?:un)?likely)\s*\(\s*$FuncArg\s*\)\s*$Compare/) {
 			WARN("LIKELY_MISUSE",
 			     "Using $1 should generally have parentheses around the comparison\n" . $herecurr);
 		}
 
+# nested likely/unlikely calls
+		if ($line =~ /\b(?:(?:un)?likely)\s*\(\s*!?\s*(IS_ERR(?:_OR_NULL|_VALUE)?|WARN)/) {
+			WARN("LIKELY_MISUSE",
+			     "nested (un)?likely() calls, $1 already uses unlikely() internally\n" . $herecurr);
+		}
+
 # whine mightly about in_atomic
 		if ($line =~ /\bin_atomic\s*\(/) {
 			if ($realfile =~ m@^drivers/@) {
@@ -6341,7 +6550,7 @@ sub process {
 # check for DEVICE_ATTR uses that could be DEVICE_ATTR_<FOO>
 # and whether or not function naming is typical and if
 # DEVICE_ATTR permissions uses are unusual too
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $stat =~ /\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?\s*(\s*(?:${multi_mode_perms_string_search}|0[0-7]{3,3})\s*)\s*\)?\s*,\s*(\w+)\s*,\s*(\w+)\s*\)/) {
 			my $var = $1;
@@ -6401,7 +6610,7 @@ sub process {
 #   specific definition of not visible in sysfs.
 # o Ignore proc_create*(...) uses with a decimal 0 permission as that means
 #   use the default permissions
-		if ($^V && $^V ge 5.10.0 &&
+		if ($perl_version_ok &&
 		    defined $stat &&
 		    $line =~ /$mode_perms_search/) {
 			foreach my $entry (@mode_permission_funcs) {
@@ -6463,6 +6672,12 @@ sub process {
 				     "unknown module license " . $extracted_string . "\n" . $herecurr);
 			}
 		}
+
+# check for sysctl duplicate constants
+		if ($line =~ /\.extra[12]\s*=\s*&(zero|one|int_max)\b/) {
+			WARN("DUPLICATED_SYSCTL_CONST",
+				"duplicated sysctl range checking value '$1', consider using the shared one in include/linux/sysctl.h\n" . $herecurr);
+		}
 	}
 
 	# If we have no input at all, then there is nothing to report on
@@ -6487,9 +6702,14 @@ sub process {
 		ERROR("NOT_UNIFIED_DIFF",
 		      "Does not appear to be a unified-diff format patch\n");
 	}
-	if ($is_patch && $has_commit_log && $chk_signoff && $signoff == 0) {
-		ERROR("MISSING_SIGN_OFF",
-		      "Missing Signed-off-by: line(s)\n");
+	if ($is_patch && $has_commit_log && $chk_signoff) {
+		if ($signoff == 0) {
+			ERROR("MISSING_SIGN_OFF",
+			      "Missing Signed-off-by: line(s)\n");
+		} elsif (!$authorsignoff) {
+			WARN("NO_AUTHOR_SIGN_OFF",
+			     "Missing Signed-off-by: line by nominal patch author '$author'\n");
+		}
 	}
 
 	print report_dump();