[PATCH 2/6] USB: Fix race between autosuspend and unregister for root hubs

THis patch (as890) fixes a race between autosuspending a root hub and
unregistering it.

Signed-off-by: Alan Stern <[email protected]>

---

Index: usb-2.6/drivers/usb/core/hub.c
===================================================================
--- usb-2.6.orig/drivers/usb/core/hub.c
+++ usb-2.6/drivers/usb/core/hub.c
@@ -1335,13 +1335,14 @@ void usb_disconnect(struct usb_device **
 	*pdev = NULL;
 	spin_unlock_irq(&device_state_lock);
 
-	/* Decrement the parent's count of unsuspended children */
-	if (udev->parent) {
-		usb_pm_lock(udev);
-		if (!udev->discon_suspended)
-			usb_autosuspend_device(udev->parent);
-		usb_pm_unlock(udev);
-	}
+	/* Synchronize with the ksuspend thread to prevent any more
+	 * autosuspend requests from being submitted, and decrement
+	 * the parent's count of unsuspended children.
+	 */
+	usb_pm_lock(udev);
+	if (udev->parent && !udev->discon_suspended)
+		usb_autosuspend_device(udev->parent);
+	usb_pm_unlock(udev);
 
 	put_device(&udev->dev);
 }


-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel