4 files changed, 44 insertions, 8 deletions

diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index 566d9f94f735..9a56e3adf476 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -73,7 +73,7 @@ set_bConfigurationValue(struct device *dev, struct device_attribute *attr,
         return (value < 0) ? value : count;
 }
 
-static DEVICE_ATTR(bConfigurationValue, S_IRUGO | S_IWUSR,
+static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
                 show_bConfigurationValue, set_bConfigurationValue);
 
 /* String fields */
@@ -595,7 +595,7 @@ static ssize_t usb_dev_authorized_store(struct device *dev,
         return result < 0? result : size;
 }
 
-static DEVICE_ATTR(authorized, 0644,
+static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, 0644,
             usb_dev_authorized_show, usb_dev_authorized_store);
 
 /* "Safely remove a device" */
@@ -618,7 +618,7 @@ static ssize_t usb_remove_store(struct device *dev,
         usb_unlock_device(udev);
         return rc;
 }
-static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
+static DEVICE_ATTR_IGNORE_LOCKDEP(remove, 0200, NULL, usb_remove_store);
 
 
 static struct attribute *dev_attrs[] = {
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 24fa995f0312..e6bb9b2a4cbe 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -132,6 +132,24 @@ static void sysfs_unlink_sibling(struct sysfs_dirent *sd)
         rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children);
 }
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+/* Test for attributes that want to ignore lockdep for read-locking */
+static bool ignore_lockdep(struct sysfs_dirent *sd)
+{
+        return sysfs_type(sd) == SYSFS_KOBJ_ATTR &&
+                        sd->s_attr.attr->ignore_lockdep;
+}
+
+#else
+
+static inline bool ignore_lockdep(struct sysfs_dirent *sd)
+{
+        return true;
+}
+
+#endif
+
 /**
  *      sysfs_get_active - get an active reference to sysfs_dirent
  *      @sd: sysfs_dirent to get an active reference to
@@ -155,15 +173,17 @@ struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
                         return NULL;
 
                 t = atomic_cmpxchg(&sd->s_active, v, v + 1);
-                if (likely(t == v)) {
-                        rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_);
-                        return sd;
-                }
+                if (likely(t == v))
+                        break;
                 if (t < 0)
                         return NULL;
 
                 cpu_relax();
         }
+
+        if (likely(!ignore_lockdep(sd)))
+                rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_);
+        return sd;
 }
 
 /**
@@ -180,7 +200,8 @@ void sysfs_put_active(struct sysfs_dirent *sd)
         if (unlikely(!sd))
                 return;
 
-        rwsem_release(&sd->dep_map, 1, _RET_IP_);
+        if (likely(!ignore_lockdep(sd)))
+                rwsem_release(&sd->dep_map, 1, _RET_IP_);
         v = atomic_dec_return(&sd->s_active);
         if (likely(v != SD_DEACTIVATED_BIAS))
                 return;
diff --git a/include/linux/device.h b/include/linux/device.h
index a8db2cfa2c81..e04f5776f6d0 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -504,6 +504,9 @@ ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
 #define DEVICE_INT_ATTR(_name, _mode, _var) \
         struct dev_ext_attribute dev_attr_##_name = \
                 { __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
+#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
+        struct device_attribute dev_attr_##_name =              \
+                __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
 
 extern int device_create_file(struct device *device,
                               const struct device_attribute *entry);
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 0010009b2f00..381f06db2fe5 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -27,6 +27,7 @@ struct attribute {
         const char              *name;
         umode_t                 mode;
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
+        bool                    ignore_lockdep:1;
         struct lock_class_key   *key;
         struct lock_class_key   skey;
 #endif
@@ -80,6 +81,17 @@ struct attribute_group {
 
 #define __ATTR_NULL { .attr = { .name = NULL } }
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+#define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {    \
+        .attr = {.name = __stringify(_name), .mode = _mode,     \
+                        .ignore_lockdep = true },               \
+        .show           = _show,                                \
+        .store          = _store,                               \
+}
+#else
+#define __ATTR_IGNORE_LOCKDEP   __ATTR
+#endif
+
 #define attr_name(_attr) (_attr).attr.name
 
 struct file;