diff options
Diffstat (limited to 'drivers/usb/core/port.c')
| -rw-r--r-- | drivers/usb/core/port.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c index 38c1a4f4f..e91fa567d 100644 --- a/drivers/usb/core/port.c +++ b/drivers/usb/core/port.c @@ -28,11 +28,22 @@ static ssize_t disable_show(struct device *dev, u16 portstatus, unused; bool disabled; int rc; + struct kernfs_node *kn; + hub_get(hub); rc = usb_autopm_get_interface(intf); if (rc < 0) - return rc; + goto out_hub_get; + /* + * Prevent deadlock if another process is concurrently + * trying to unregister hdev. + */ + kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); + if (!kn) { + rc = -ENODEV; + goto out_autopm; + } usb_lock_device(hdev); if (hub->disconnected) { rc = -ENODEV; @@ -42,9 +53,13 @@ static ssize_t disable_show(struct device *dev, usb_hub_port_status(hub, port1, &portstatus, &unused); disabled = !usb_port_is_power_on(hub, portstatus); -out_hdev_lock: + out_hdev_lock: usb_unlock_device(hdev); + sysfs_unbreak_active_protection(kn); + out_autopm: usb_autopm_put_interface(intf); + out_hub_get: + hub_put(hub); if (rc) return rc; @@ -62,15 +77,26 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr, int port1 = port_dev->portnum; bool disabled; int rc; + struct kernfs_node *kn; rc = strtobool(buf, &disabled); if (rc) return rc; + hub_get(hub); rc = usb_autopm_get_interface(intf); if (rc < 0) - return rc; + goto out_hub_get; + /* + * Prevent deadlock if another process is concurrently + * trying to unregister hdev. + */ + kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); + if (!kn) { + rc = -ENODEV; + goto out_autopm; + } usb_lock_device(hdev); if (hub->disconnected) { rc = -ENODEV; @@ -91,9 +117,13 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr, if (!rc) rc = count; -out_hdev_lock: + out_hdev_lock: usb_unlock_device(hdev); + sysfs_unbreak_active_protection(kn); + out_autopm: usb_autopm_put_interface(intf); + out_hub_get: + hub_put(hub); return rc; } @@ -534,7 +564,7 @@ static int match_location(struct usb_device *peer_hdev, void *p) struct usb_hub *peer_hub = usb_hub_to_struct_hub(peer_hdev); struct usb_device *hdev = to_usb_device(port_dev->dev.parent->parent); - if (!peer_hub) + if (!peer_hub || port_dev->connect_type == USB_PORT_NOT_USED) return 0; hcd = bus_to_hcd(hdev->bus); @@ -545,7 +575,8 @@ static int match_location(struct usb_device *peer_hdev, void *p) for (port1 = 1; port1 <= peer_hdev->maxchild; port1++) { peer = peer_hub->ports[port1 - 1]; - if (peer && peer->location == port_dev->location) { + if (peer && peer->connect_type != USB_PORT_NOT_USED && + peer->location == port_dev->location) { link_peers_report(port_dev, peer); return 1; /* done */ } |