lockdep: Add novalidate class for dev->mutex conversion
The conversion of device->sem to device->mutex resulted in lockdep
warnings. Create a novalidate class for now until the driver folks
come up with separate classes. That way we have at least the basic
mutex debugging coverage.
Add a checkpatch error so the usage is reserved for device->mutex.
[ tglx: checkpatch and compile fix for LOCKDEP=n ]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a4d7434..f2bbea9 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2656,6 +2656,7 @@
# check for semaphores used as mutexes
if ($line =~ /^.\s*init_MUTEX_LOCKED\s*\(/) {
WARN("consider using a completion\n" . $herecurr);
+
}
# recommend strict_strto* over simple_strto*
if ($line =~ /\bsimple_(strto.*?)\s*\(/) {
@@ -2740,6 +2741,16 @@
WARN("use of in_atomic() is incorrect outside core kernel code\n" . $herecurr);
}
}
+
+# check for lockdep_set_novalidate_class
+ if ($line =~ /^.\s*lockdep_set_novalidate_class\s*\(/ ||
+ $line =~ /__lockdep_no_validate__\s*\)/ ) {
+ if ($realfile !~ m@^kernel/lockdep@ &&
+ $realfile !~ m@^include/linux/lockdep@ &&
+ $realfile !~ m@^drivers/base/core@) {
+ ERROR("lockdep_no_validate class is reserved for device->mutex.\n" . $herecurr);
+ }
+ }
}
# If we have no input at all, then there is nothing to report on
