Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933551AbcKVV4D (ORCPT ); Tue, 22 Nov 2016 16:56:03 -0500 Received: from coyote.holtmann.net ([212.227.132.17]:44595 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752142AbcKVVzr (ORCPT ); Tue, 22 Nov 2016 16:55:47 -0500 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 10.1 \(3251\)) Subject: Re: [PATCH] btusb: fix zero BD address problem during stress test From: Marcel Holtmann In-Reply-To: Date: Tue, 22 Nov 2016 22:55:10 +0100 Cc: "linux-bluetooth@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Cathy Luo , Nishant Sarmukadam , Ganapathi Bhat Content-Transfer-Encoding: 7bit Message-Id: <077FBE27-DA84-4F11-BC69-F38184CE6B40@holtmann.org> References: <1476795449-20592-1-git-send-email-akarwar@marvell.com> To: Amitkumar Karwar X-Mailer: Apple Mail (2.3251) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2099 Lines: 57 Hi Amitkumar, >> From: Amitkumar Karwar [mailto:akarwar@marvell.com] >> Sent: Tuesday, October 18, 2016 6:27 PM >> To: linux-bluetooth@vger.kernel.org >> Cc: marcel@holtmann.org; linux-kernel@vger.kernel.org; Cathy Luo; >> Nishant Sarmukadam; Ganapathi Bhat; Amitkumar Karwar >> Subject: [PATCH] btusb: fix zero BD address problem during stress test >> >> From: Ganapathi Bhat >> >> 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 >> Signed-off-by: Amitkumar Karwar >> --- >> 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, > > Did you get a chance to check this? > Please let us know if you have any review comments. can you explain how this is correct and show me the HCI traces for this. Regards Marcel