This is a note to let you know that I've just added the patch titled

    usb: hub: take hub->hdev reference when processing from eventlist

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-hub-take-hub-hdev-reference-when-processing-from-eventlist.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From c605f3cdff53a743f6d875b76956b239deca1272 Mon Sep 17 00:00:00 2001
From: Joe Lawrence <[email protected]>
Date: Wed, 10 Sep 2014 15:07:50 -0400
Subject: usb: hub: take hub->hdev reference when processing from eventlist

From: Joe Lawrence <[email protected]>

commit c605f3cdff53a743f6d875b76956b239deca1272 upstream.

During surprise device hotplug removal tests, it was observed that
hub_events may try to call usb_lock_device on a device that has already
been freed. Protect the usb_device by taking out a reference (under the
hub_event_lock) when hub_events pulls it off the list, returning the
reference after hub_events is finished using it.

Signed-off-by: Joe Lawrence <[email protected]>
Suggested-by: David Bulkow <[email protected]> for using kref
Suggested-by: Alan Stern <[email protected]> for placement
Acked-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/usb/core/hub.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4702,9 +4702,10 @@ static void hub_events(void)
 
                hub = list_entry(tmp, struct usb_hub, event_list);
                kref_get(&hub->kref);
+               hdev = hub->hdev;
+               usb_get_dev(hdev);
                spin_unlock_irq(&hub_event_lock);
 
-               hdev = hub->hdev;
                hub_dev = hub->intfdev;
                intf = to_usb_interface(hub_dev);
                dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
@@ -4919,6 +4920,7 @@ static void hub_events(void)
                usb_autopm_put_interface(intf);
  loop_disconnected:
                usb_unlock_device(hdev);
+               usb_put_dev(hdev);
                kref_put(&hub->kref, hub_release);
 
         } /* end while (1) */


Patches currently in stable-queue which might be from [email protected] 
are

queue-3.10/usb-hub-take-hub-hdev-reference-when-processing-from-eventlist.patch
queue-3.10/usb-ehci-unlink-qhs-even-after-the-controller-has-stopped.patch
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