Return-path: Received: from mx0a-0016f401.pphosted.com ([67.231.148.174]:56184 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726593AbeHULNN (ORCPT ); Tue, 21 Aug 2018 07:13:13 -0400 From: Ganapathi Bhat To: CC: Brian Norris , Cathy Luo , Zhiyuan Yang , James Cao , Rakesh Parmar , Vidya Dharmaraju , Ganapathi Bhat Subject: [PATCH 1/2] mwifiex: do no submit URB in suspended state Date: Tue, 21 Aug 2018 13:23:01 +0530 Message-ID: <1534837982-31206-1-git-send-email-gbhat@marvell.com> (sfid-20180821_095412_077232_525AD007) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: There is a possible race between USB suspend and main thread: 1. After processing the command response, main thread will submit rx_cmd URB back so as to process next command response, by calling mwifiex_usb_submit_rx_urb. 2. During USB suspend, the suspend handler will check if rx_cmd URB is pending(submitted) and if true, kill this URB. There is a possible race between #1 and #2, where rx_cmd URB will be submitted by main thread(#1) after the suspend handler check in #2. To fix this, check if device is already suspended in mwifiex_usb_submit_rx_urb, in which case do not submit the URB. Signed-off-by: Vidya Dharmaraju Signed-off-by: Cathy Luo Signed-off-by: Ganapathi Bhat --- drivers/net/wireless/marvell/mwifiex/usb.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c index 433c6a16..76d80fd 100644 --- a/drivers/net/wireless/marvell/mwifiex/usb.c +++ b/drivers/net/wireless/marvell/mwifiex/usb.c @@ -298,6 +298,13 @@ static int mwifiex_usb_submit_rx_urb(struct urb_context *ctx, int size) struct mwifiex_adapter *adapter = ctx->adapter; struct usb_card_rec *card = (struct usb_card_rec *)adapter->card; + if (test_bit(MWIFIEX_IS_SUSPENDED, &adapter->work_flags)) { + mwifiex_dbg(adapter, ERROR, + "%s: card removed/suspended, EP %d rx_cmd URB submit skipped\n", + __func__, ctx->ep); + return -1; + } + if (card->rx_cmd_ep != ctx->ep) { ctx->skb = dev_alloc_skb(size); if (!ctx->skb) { -- 1.9.1