hcd_urb_list_lock is used for synchronization between IRQ and non-IRQ
contexts, so the non-IRQ context has to disable IRQs in order to prevent
deadlocking with IRQ context.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
drivers/usb/core/hcd.c | 10 ++++++----
1 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index bf10e9c..19279ed 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1000,8 +1000,9 @@ EXPORT_SYMBOL_GPL(usb_calc_bus_time);
int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
{
int rc = 0;
+ unsigned long flags;
- spin_lock(&hcd_urb_list_lock);
+ spin_lock_irqsave(&hcd_urb_list_lock, flags);
/* Check that the URB isn't being killed */
if (unlikely(urb->reject)) {
@@ -1034,7 +1035,7 @@ int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
goto done;
}
done:
- spin_unlock(&hcd_urb_list_lock);
+ spin_unlock_irqrestore(&hcd_urb_list_lock, flags);
return rc;
}
EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
@@ -1106,10 +1107,11 @@ EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
*/
void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
{
+ unsigned long flags;
/* clear all state linking urb to this dev (and hcd) */
- spin_lock(&hcd_urb_list_lock);
+ spin_lock_irqsave(&hcd_urb_list_lock, flags);
list_del_init(&urb->urb_list);
- spin_unlock(&hcd_urb_list_lock);
+ spin_unlock_irqrestore(&hcd_urb_list_lock, flags);
}
EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
--
