staging: usbip: bugfix for deadlock

Interrupts must be disabled prior to calling usb_hcd_unlink_urb_from_ep.
If interrupts are not disabled, it can potentially lead to a deadlock.
The deadlock is readily reproduceable on a slower (ARM based) device
such as the TI Pandaboard.

Signed-off-by: Bart Westgeest <bart@elbrys.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Bart Westgeest 2011-11-01 15:01:28 -04:00 committed by Greg Kroah-Hartman
parent caca6a03d3
commit 438957f8d4
1 changed files with 6 additions and 4 deletions

View File

@ -68,6 +68,7 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
{
struct usbip_device *ud = &vdev->ud;
struct urb *urb;
unsigned long flags;
spin_lock(&vdev->priv_lock);
urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
@ -101,9 +102,9 @@ static void vhci_recv_ret_submit(struct vhci_device *vdev,
usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
spin_lock(&the_controller->lock);
spin_lock_irqsave(&the_controller->lock, flags);
usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
spin_unlock(&the_controller->lock);
spin_unlock_irqrestore(&the_controller->lock, flags);
usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
@ -141,6 +142,7 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
{
struct vhci_unlink *unlink;
struct urb *urb;
unsigned long flags;
usbip_dump_header(pdu);
@ -170,9 +172,9 @@ static void vhci_recv_ret_unlink(struct vhci_device *vdev,
urb->status = pdu->u.ret_unlink.status;
pr_info("urb->status %d\n", urb->status);
spin_lock(&the_controller->lock);
spin_lock_irqsave(&the_controller->lock, flags);
usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
spin_unlock(&the_controller->lock);
spin_unlock_irqrestore(&the_controller->lock, flags);
usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
urb->status);