USB: hub.c loops forever on resume from ram due to bluetooth
authorMark Lord <lkml@rtr.ca>
Mon, 14 May 2007 23:48:02 +0000 (19:48 -0400)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 12 Jul 2007 23:29:48 +0000 (16:29 -0700)
Okay, found it.  The root cause here was a missing CONFIG_USB_SUSPEND=y,
which means the hci_usb device never got marked as USB_STATE_SUSPENDED,
which then caused the loop to go on forever.

The system works fine now with CONFIG_USB_SUSPEND=y in the .config.

Here's the patch to prevent future lockups for this or other causes.
I no longer need it, but it does still seem a good idea.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hub.c

index f4ef7c25096e69e33a52306a27c6ce4b5ccc430b..08f0c22fa9173d49bf1dcdc706c3dfb51c997213 100644 (file)
@@ -403,9 +403,10 @@ static void hub_tt_kevent (struct work_struct *work)
        struct usb_hub          *hub =
                container_of(work, struct usb_hub, tt.kevent);
        unsigned long           flags;
+       int                     limit = 100;
 
        spin_lock_irqsave (&hub->tt.lock, flags);
-       while (!list_empty (&hub->tt.clear_list)) {
+       while (--limit && !list_empty (&hub->tt.clear_list)) {
                struct list_head        *temp;
                struct usb_tt_clear     *clear;
                struct usb_device       *hdev = hub->hdev;