summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMathias Nyman <mathias.nyman@linux.intel.com>2013-09-05 11:01:20 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-10-05 07:17:56 -0700
commit0e6cddf45f3f89761ebcd9bc075a09d4c6e79424 (patch)
treeed3faad1df29d61e3fe296ad43bad3e188768b46
parent1aa5cef25626ff72aff29658379f1386ffb2092f (diff)
xhci: Fix oops happening after address device timeout
commit 284d20552461466b04d6bfeafeb1c47a8891b591 upstream. When a command times out, the command ring is first aborted, and then stopped. If the command ring is empty when it is stopped the stop event will point to next command which is not yet set. xHCI tries to handle this next event often causing an oops. Don't handle command completion events on stopped cmd ring if ring is empty. This patch should be backported to kernels as old as 3.7, that contain the commit b92cc66c047ff7cf587b318fe377061a353c120f "xHCI: add aborting command ring function" Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Reported-by: Giovanni <giovanni.nervi@yahoo.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/host/xhci-ring.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 3a463b87d44e..31386f4afddf 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1400,6 +1400,12 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
inc_deq(xhci, xhci->cmd_ring);
return;
}
+ /* There is no command to handle if we get a stop event when the
+ * command ring is empty, event->cmd_trb points to the next
+ * unset command
+ */
+ if (xhci->cmd_ring->dequeue == xhci->cmd_ring->enqueue)
+ return;
}
switch (le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3])