From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932263Ab2CMASR (ORCPT ); Mon, 12 Mar 2012 20:18:17 -0400 Received: from mail.windriver.com ([147.11.1.11]:46846 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932137Ab2CMASM (ORCPT ); Mon, 12 Mar 2012 20:18:12 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Arjan Mels , Takahiro Hirofuchi , Max Vozeler , Arnd Bergmann , Greg Kroah-Hartman , Paul Gortmaker Subject: [34-longterm 016/196] staging: usbip: bugfixes related to kthread conversion Date: Mon, 12 Mar 2012 20:12:24 -0400 Message-Id: <1331597724-31358-17-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.9.3 In-Reply-To: <1331597724-31358-1-git-send-email-paul.gortmaker@windriver.com> References: <1331597724-31358-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arjan Mels ------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. ------------------- commit d2dd0b07c3e725d386d20294ec906f7ddef207fa upstream. When doing a usb port reset do a queued reset instead to prevent a deadlock: the reset will cause the driver to unbind, causing the usb_driver_lock_for_reset to stall. Signed-off-by: Arjan Mels Cc: Takahiro Hirofuchi Cc: Max Vozeler Cc: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman Signed-off-by: Paul Gortmaker --- drivers/staging/usbip/stub_rx.c | 40 +++++++++++++++------------------------ 1 file changed, 15 insertions(+), 25 deletions(-) diff --git a/drivers/staging/usbip/stub_rx.c b/drivers/staging/usbip/stub_rx.c index bc26740..16a7df1 100644 --- a/drivers/staging/usbip/stub_rx.c +++ b/drivers/staging/usbip/stub_rx.c @@ -170,33 +170,23 @@ static int tweak_set_configuration_cmd(struct urb *urb) static int tweak_reset_device_cmd(struct urb *urb) { - struct usb_ctrlrequest *req; - __u16 value; - __u16 index; - int ret; - - req = (struct usb_ctrlrequest *) urb->setup_packet; - value = le16_to_cpu(req->wValue); - index = le16_to_cpu(req->wIndex); - - usbip_uinfo("reset_device (port %d) to %s\n", index, - dev_name(&urb->dev->dev)); + struct stub_priv *priv = (struct stub_priv *) urb->context; + struct stub_device *sdev = priv->sdev; - /* all interfaces should be owned by usbip driver, so just reset it. */ - ret = usb_lock_device_for_reset(urb->dev, NULL); - if (ret < 0) { - dev_err(&urb->dev->dev, "lock for reset\n"); - return ret; - } - - /* try to reset the device */ - ret = usb_reset_device(urb->dev); - if (ret < 0) - dev_err(&urb->dev->dev, "device reset\n"); + usbip_uinfo("reset_device %s\n", dev_name(&urb->dev->dev)); - usb_unlock_device(urb->dev); - - return ret; + /* + * usb_lock_device_for_reset caused a deadlock: it causes the driver + * to unbind. In the shutdown the rx thread is signalled to shut down + * but this thread is pending in the usb_lock_device_for_reset. + * + * Instead queue the reset. + * + * Unfortunatly an existing usbip connection will be dropped due to + * driver unbinding. + */ + usb_queue_reset_device(sdev->interface); + return 0; } /* -- 1.7.9.3