Add a comment in chrdev_open()
I stared at this code for a while and almost deleted it before
understanding crept into my slow brain. Hopefully this makes life easier
for the next person to happen on it.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/fs/char_dev.c b/fs/char_dev.c
index 68e510b..a54d693 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -373,6 +373,8 @@
return -ENXIO;
new = container_of(kobj, struct cdev, kobj);
spin_lock(&cdev_lock);
+ /* Check i_cdev again in case somebody beat us to it while
+ we dropped the lock. */
p = inode->i_cdev;
if (!p) {
inode->i_cdev = p = new;