diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index 5e0e31cc46f5..9889e54e1f13 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -109,6 +109,17 @@ static inline void set_inode_attr(struct inode * inode, struct iattr * iattr) inode->i_ctime = iattr->ia_ctime; } + +/* + * sysfs has a different i_mutex lock order behavior for i_mutex than other + * filesystems; sysfs i_mutex is called in many places with subsystem locks + * held. At the same time, many of the VFS locking rules do not apply to + * sysfs at all (cross directory rename for example). To untangle this mess + * (which gives false positives in lockdep), we're giving sysfs inodes their + * own class for i_mutex. + */ +static struct lock_class_key sysfs_inode_imutex_key; + struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd) { struct inode * inode = new_inode(sysfs_sb); @@ -118,6 +129,7 @@ struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd) inode->i_mapping->a_ops = &sysfs_aops; inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info; inode->i_op = &sysfs_inode_operations; + lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key); if (sd->s_iattr) { /* sysfs_dirent has non-default attributes