From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932560AbcHKCeu (ORCPT ); Wed, 10 Aug 2016 22:34:50 -0400 Received: from mga14.intel.com ([192.55.52.115]:57388 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243AbcHKCes (ORCPT ); Wed, 10 Aug 2016 22:34:48 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,503,1464678000"; d="scan'208";a="863430739" From: Lu Baolu To: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Lu Baolu , stable@vger.kernel.org, Alan Stern Subject: [PATCH v3 1/1] usb: misc: usbtest: add fix for driver hang Date: Thu, 11 Aug 2016 10:31:14 +0800 Message-Id: <1470882690-8270-1-git-send-email-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In sg_timeout(), req->status is set to "-ETIMEDOUT" before calling into usb_sg_cancel(). usb_sg_cancel() will do nothing and return directly if req->status has been set to a non-zero value. This will cause driver hang whenever transfer time out is triggered. This patch fixes this issue. It could be backported to stable kernel with version later than v3.15. Cc: stable@vger.kernel.org # 3.15+ Cc: Alan Stern Signed-off-by: Lu Baolu Suggested-by: Alan Stern Acked-by: Alan Stern --- v1->v2: - Set retval to -ETIMEDOUT after timed out - Removed the kernel log in patch description v2->v3: - Removed unlikely() - Added Acked-by Alan drivers/usb/misc/usbtest.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c index 6b978f0..07db7c6 100644 --- a/drivers/usb/misc/usbtest.c +++ b/drivers/usb/misc/usbtest.c @@ -585,7 +585,6 @@ static void sg_timeout(unsigned long _req) { struct usb_sg_request *req = (struct usb_sg_request *) _req; - req->status = -ETIMEDOUT; usb_sg_cancel(req); } @@ -616,8 +615,10 @@ static int perform_sglist( mod_timer(&sg_timer, jiffies + msecs_to_jiffies(SIMPLE_IO_TIMEOUT)); usb_sg_wait(req); - del_timer_sync(&sg_timer); - retval = req->status; + if (!del_timer_sync(&sg_timer)) + retval = -ETIMEDOUT; + else + retval = req->status; /* FIXME check resulting data pattern */ -- 2.1.4