| Message ID | 20240822223717.253433-1-amitsd@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] usb: roles: add lockdep class key to struct usb_role_switch | expand |
On Thu, Aug 22, 2024 at 03:37:15PM -0700, Amit Sunil Dhamne wrote: > There can be multiple role switch devices running on a platform. Given > that lockdep is not capable of differentiating between locks of > different instances, false positive warnings for circular locking are > reported. To prevent this, register unique lockdep key for each of the > individual instances. > > Signed-off-by: Amit Sunil Dhamne <amitsd@google.com> > Reviewed-by: Badhri Jagan Sridharan <badhri@google.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > v1->v2 > - Avoid usage of ifdefs. > v2->v3 > - Removed redundancies. > - Completed peer review and added reviewer signature. > --- > drivers/usb/roles/class.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c > index d7aa913ceb8a..7aca1ef7f44c 100644 > --- a/drivers/usb/roles/class.c > +++ b/drivers/usb/roles/class.c > @@ -11,6 +11,7 @@ > #include <linux/usb/role.h> > #include <linux/property.h> > #include <linux/device.h> > +#include <linux/lockdep.h> > #include <linux/module.h> > #include <linux/mutex.h> > #include <linux/slab.h> > @@ -33,6 +34,8 @@ struct usb_role_switch { > usb_role_switch_set_t set; > usb_role_switch_get_t get; > bool allow_userspace_control; > + > + struct lock_class_key key; > }; > > #define to_role_switch(d) container_of(d, struct usb_role_switch, dev) > @@ -396,6 +399,9 @@ usb_role_switch_register(struct device *parent, > > sw->registered = true; > > + lockdep_register_key(&sw->key); > + lockdep_set_class(&sw->lock, &sw->key); > + > /* TODO: Symlinks for the host port and the device controller. */ > > return sw; > @@ -412,6 +418,9 @@ void usb_role_switch_unregister(struct usb_role_switch *sw) > { > if (IS_ERR_OR_NULL(sw)) > return; > + > + lockdep_unregister_key(&sw->key); > + > sw->registered = false; > if (dev_fwnode(&sw->dev)) > component_del(&sw->dev, &connector_ops); > > base-commit: ca7df2c7bb5f83fe46aa9ce998b7352c6b28f3a1 > -- > 2.46.0.184.g6999bdac58-goog
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index d7aa913ceb8a..7aca1ef7f44c 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -11,6 +11,7 @@ #include <linux/usb/role.h> #include <linux/property.h> #include <linux/device.h> +#include <linux/lockdep.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> @@ -33,6 +34,8 @@ struct usb_role_switch { usb_role_switch_set_t set; usb_role_switch_get_t get; bool allow_userspace_control; + + struct lock_class_key key; }; #define to_role_switch(d) container_of(d, struct usb_role_switch, dev) @@ -396,6 +399,9 @@ usb_role_switch_register(struct device *parent, sw->registered = true; + lockdep_register_key(&sw->key); + lockdep_set_class(&sw->lock, &sw->key); + /* TODO: Symlinks for the host port and the device controller. */ return sw; @@ -412,6 +418,9 @@ void usb_role_switch_unregister(struct usb_role_switch *sw) { if (IS_ERR_OR_NULL(sw)) return; + + lockdep_unregister_key(&sw->key); + sw->registered = false; if (dev_fwnode(&sw->dev)) component_del(&sw->dev, &connector_ops);