[101/141] usb: dwc3: gadget: free trb pool only from epnum 2

Steven Rostedt
2013-07-03T19:09:42Z

[-- Attachment #1: 0101-usb-dwc3-gadget-free-trb-pool-only-from-epnum-2.patch --]
[-- Type: text/plain, Size: 1755 bytes --]

3.6.11.6 stable review patch.
If anyone has any objections, please let me know.

------------------

From: George Cherian <george.cherian@ti.com>

[ Upstream commit 5bf8fae33d14cc5c3c53a926f9079f92c8b082b0 ]

we never allocate a TRB pool for physical endpoints
0 and 1 so trying to free it (a invalid TRB pool pointer)
will lead us in a warning while removing dwc3.ko module.

In order to fix the situation, all we have to do is skip
dwc3_free_trb_pool() for physical endpoints 0 and 1 just
as we while deleting endpoints from the endpoints list.

Cc: stable@vger.kernel.org
Signed-off-by: George Cherian <george.cherian@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
drivers/usb/dwc3/gadget.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index eb0fd10..8212dbb 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1650,10 +1650,21 @@ static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)

for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
dep = dwc->eps[epnum];
- dwc3_free_trb_pool(dep);
-
- if (epnum != 0 && epnum != 1)
+ if (!dep)
+ continue;
+ /*
+ * Physical endpoints 0 and 1 are special; they form the
+ * bi-directional USB endpoint 0.
+ *
+ * For those two physical endpoints, we don't allocate a TRB
+ * pool nor do we add them the endpoints list. Due to that, we
+ * shouldn't do these two operations otherwise we would end up
+ * with all sorts of bugs when removing dwc3.ko.
+ */
+ if (epnum != 0 && epnum != 1) {
+ dwc3_free_trb_pool(dep);
list_del(&dep->endpoint.ep_list);
+ }

kfree(dep);
}
--
1.7.10.4