diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index 4a5863b79de9..fa053151fa96 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -421,6 +421,16 @@ static int kernfs_file_mmap(struct file *file, struct vm_area_struct *vma)
 	const struct kernfs_ops *ops;
 	int rc;
 
+	/*
+	 * mmap path and of->mutex are prone to triggering spurious lockdep
+	 * warnings and we don't want to add spurious locking dependency
+	 * between the two.  Check whether mmap is actually implemented
+	 * without grabbing @of->mutex by testing HAS_MMAP flag.  See the
+	 * comment in kernfs_file_open() for more details.
+	 */
+	if (!(of->sd->s_flags & SYSFS_FLAG_HAS_MMAP))
+		return -ENODEV;
+
 	mutex_lock(&of->mutex);
 
 	rc = -ENODEV;
@@ -428,10 +438,7 @@ static int kernfs_file_mmap(struct file *file, struct vm_area_struct *vma)
 		goto out_unlock;
 
 	ops = kernfs_ops(of->sd);
-	if (ops->mmap)
-		rc = ops->mmap(of, vma);
-	if (rc)
-		goto out_put;
+	rc = ops->mmap(of, vma);
 
 	/*
 	 * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
@@ -596,6 +603,9 @@ static int kernfs_file_open(struct inode *inode, struct file *file)
 	 * happen on the same file.  At this point, we can't easily give
 	 * each file a separate locking class.  Let's differentiate on
 	 * whether the file has mmap or not for now.
+	 *
+	 * Both paths of the branch look the same.  They're supposed to
+	 * look that way and give @of->mutex different static lockdep keys.
 	 */
 	if (has_mmap)
 		mutex_init(&of->mutex);
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index ac77d2be3c31..a67d1c682fed 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -142,9 +142,6 @@ static int sysfs_kf_bin_mmap(struct sysfs_open_file *of,
 	struct bin_attribute *battr = of->sd->priv;
 	struct kobject *kobj = of->sd->s_parent->priv;
 
-	if (!battr->mmap)
-		return -ENODEV;
-
 	return battr->mmap(of->file, kobj, battr, vma);
 }
 
@@ -197,6 +194,11 @@ static const struct kernfs_ops sysfs_bin_kfops_wo = {
 static const struct kernfs_ops sysfs_bin_kfops_rw = {
 	.read		= sysfs_kf_bin_read,
 	.write		= sysfs_kf_bin_write,
+};
+
+static const struct kernfs_ops sysfs_bin_kfops_mmap = {
+	.read		= sysfs_kf_bin_read,
+	.write		= sysfs_kf_bin_write,
 	.mmap		= sysfs_kf_bin_mmap,
 };
 
@@ -232,7 +234,9 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
 	} else {
 		struct bin_attribute *battr = (void *)attr;
 
-		if ((battr->read && battr->write) || battr->mmap)
+		if (battr->mmap)
+			ops = &sysfs_bin_kfops_mmap;
+		else if (battr->read && battr->write)
 			ops = &sysfs_bin_kfops_rw;
 		else if (battr->read)
 			ops = &sysfs_bin_kfops_ro;