summaryrefslogtreecommitdiff
path: root/drivers/usb/host
diff options
context:
space:
mode:
authorMathias Nyman <mathias.nyman@linux.intel.com>2013-09-05 12:01:20 +0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-10-05 18:06:53 +0400
commitc2d27c8a10cf767f4f1d988cc545db0db82c8244 (patch)
tree3f2f25527ae690c460451c6835bab10254e3b5cf /drivers/usb/host
parentd134fa59a21d03ef3bad5f68b6eaa927a8397cae (diff)
downloadlinux-c2d27c8a10cf767f4f1d988cc545db0db82c8244.tar.xz
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>
Diffstat (limited to 'drivers/usb/host')
-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 4947af3e18a1..5f734608e571 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])