[PATCH] btusb: fix zero BD address problem during stress test

From: Amitkumar Karwar
Date: Tue Oct 18 2016 - 08:58:21 EST


From: Ganapathi Bhat <gbhat@xxxxxxxxxxx>

We came across a corner case issue during reboot stress test
in which hciconfig shows BD address is all zero. Reason is we
don't get response for HCI RESET command during initialization

The issue is tracked to a race where USB subsystem calls
btusb_intr_complete() to deliver a data(NOOP frame) received
on interrupt endpoint. HCI_RUNNING flag is not yet set by
bluetooth subsystem. So we ignore that frame and return.

As we missed to resubmit the buffer to interrupt endpoint in
this case, we don't get response for BT reset command downloaded
after this.

This patch handles the corner case to resolve zero BD address
problem.

Signed-off-by: Ganapathi Bhat <gbhat@xxxxxxxxxxx>
Signed-off-by: Amitkumar Karwar <akarwar@xxxxxxxxxxx>
---
drivers/bluetooth/btusb.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 811f9b9..b5596ac 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -607,10 +607,7 @@ static void btusb_intr_complete(struct urb *urb)
BT_DBG("%s urb %p status %d count %d", hdev->name, urb, urb->status,
urb->actual_length);

- if (!test_bit(HCI_RUNNING, &hdev->flags))
- return;
-
- if (urb->status == 0) {
+ if (urb->status == 0 && test_bit(HCI_RUNNING, &hdev->flags)) {
hdev->stat.byte_rx += urb->actual_length;

if (btusb_recv_intr(data, urb->transfer_buffer,
--
1.9.1