checkpatch: add test for positional misuse of section specifiers like __initdata
As discussed recently on the arm [1] and lm-sensors [2] lists, it is
possible to use section markers on variables in a way which gcc doesn't
understand (or at least not the way the developer intended):
static struct __initdata samsung_pll_clock exynos4_plls[nr_plls] = {
does NOT put exynos4_plls in the .initdata section. The __initdata marker
can be virtually anywhere on the line, EXCEPT right after "struct". The
preferred location is before the "=" sign if there is one, or before the
trailing ";" otherwise.
[1] http://permalink.gmane.org/gmane.linux.ports.arm.kernel/258149
[2] http://lists.lm-sensors.org/pipermail/lm-sensors/2013-August/039836.html
So, update checkpatch to find these misuses and report an error when it's
immediately after struct or union, and a warning when it's otherwise not
immediately before the ; or =.
A similar patch was suggested by Andi Kleen
https://lkml.org/lkml/2013/8/5/648
Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Andi Kleen <andi@firstfloor.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 9ba4fc4..47016c3 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -242,6 +242,8 @@
__rcu
}x;
+our $InitAttribute = qr{__(?:mem|cpu|dev|net_|)(?:initdata|initconst|init\b)};
+
# Notes to $Attribute:
# We need \b after 'init' otherwise 'initconst' will cause a false positive in a check
our $Attribute = qr{
@@ -262,7 +264,7 @@
__deprecated|
__read_mostly|
__kprobes|
- __(?:mem|cpu|dev|)(?:initdata|initconst|init\b)|
+ $InitAttribute|
____cacheline_aligned|
____cacheline_aligned_in_smp|
____cacheline_internodealigned_in_smp|
@@ -292,6 +294,7 @@
}x;
our $NonptrType;
+our $NonptrTypeWithAttr;
our $Type;
our $Declare;
@@ -354,6 +357,12 @@
qr{${Ident}_handler},
qr{${Ident}_handler_fn},
);
+our @typeListWithAttr = (
+ @typeList,
+ qr{struct\s+$InitAttribute\s+$Ident},
+ qr{union\s+$InitAttribute\s+$Ident},
+);
+
our @modifierList = (
qr{fastcall},
);
@@ -367,6 +376,7 @@
sub build_types {
my $mods = "(?x: \n" . join("|\n ", @modifierList) . "\n)";
my $all = "(?x: \n" . join("|\n ", @typeList) . "\n)";
+ my $allWithAttr = "(?x: \n" . join("|\n ", @typeListWithAttr) . "\n)";
$Modifier = qr{(?:$Attribute|$Sparse|$mods)};
$NonptrType = qr{
(?:$Modifier\s+|const\s+)*
@@ -377,6 +387,15 @@
)
(?:\s+$Modifier|\s+const)*
}x;
+ $NonptrTypeWithAttr = qr{
+ (?:$Modifier\s+|const\s+)*
+ (?:
+ (?:typeof|__typeof__)\s*\([^\)]*\)|
+ (?:$typeTypedefs\b)|
+ (?:${allWithAttr}\b)
+ )
+ (?:\s+$Modifier|\s+const)*
+ }x;
$Type = qr{
$NonptrType
(?:(?:\s|\*|\[\])+\s*const|(?:\s|\*|\[\])+|(?:\s*\[\s*\])+)?
@@ -3706,6 +3725,32 @@
}
}
+sub string_find_replace {
+ my ($string, $find, $replace) = @_;
+
+ $string =~ s/$find/$replace/g;
+
+ return $string;
+}
+
+# check for bad placement of section $InitAttribute (e.g.: __initdata)
+ if ($line =~ /(\b$InitAttribute\b)/) {
+ my $attr = $1;
+ if ($line =~ /^\+\s*static\s+(?:const\s+)?(?:$attr\s+)?($NonptrTypeWithAttr)\s+(?:$attr\s+)?($Ident(?:\[[^]]*\])?)\s*[=;]/) {
+ my $ptr = $1;
+ my $var = $2;
+ if ((($ptr =~ /\b(union|struct)\s+$attr\b/ &&
+ ERROR("MISPLACED_INIT",
+ "$attr should be placed after $var\n" . $herecurr)) ||
+ ($ptr !~ /\b(union|struct)\s+$attr\b/ &&
+ WARN("MISPLACED_INIT",
+ "$attr should be placed after $var\n" . $herecurr))) &&
+ $fix) {
+ $fixed[$linenr - 1] =~ s/(\bstatic\s+(?:const\s+)?)(?:$attr\s+)?($NonptrTypeWithAttr)\s+(?:$attr\s+)?($Ident(?:\[[^]]*\])?)\s*([=;])\s*/"$1" . trim(string_find_replace($2, "\\s*$attr\\s*", " ")) . " " . trim(string_find_replace($3, "\\s*$attr\\s*", "")) . " $attr" . ("$4" eq ";" ? ";" : " = ")/e;
+ }
+ }
+ }
+
# prefer usleep_range over udelay
if ($line =~ /\budelay\s*\(\s*(\d+)\s*\)/) {
# ignore udelay's < 10, however