Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757421Ab1DLO5o (ORCPT ); Tue, 12 Apr 2011 10:57:44 -0400 Received: from kroah.org ([198.145.64.141]:57426 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757038Ab1DLOhl (ORCPT ); Tue, 12 Apr 2011 10:37:41 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Tue Apr 12 07:35:49 2011 Message-Id: <20110412143549.837107029@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Tue, 12 Apr 2011 07:34:07 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Arjan Mels , Takahiro Hirofuchi , Max Vozeler , Arnd Bergmann Subject: [018/105] staging: usbip: bugfixes related to kthread conversion In-Reply-To: <20110412143613.GA19478@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2436 Lines: 80 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Arjan Mels 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 --- drivers/staging/usbip/stub_rx.c | 40 +++++++++++++++------------------------- 1 file changed, 15 insertions(+), 25 deletions(-) --- a/drivers/staging/usbip/stub_rx.c +++ b/drivers/staging/usbip/stub_rx.c @@ -170,33 +170,23 @@ static int tweak_set_configuration_cmd(s static int tweak_reset_device_cmd(struct urb *urb) { - struct usb_ctrlrequest *req; - __u16 value; - __u16 index; - int ret; + struct stub_priv *priv = (struct stub_priv *) urb->context; + struct stub_device *sdev = priv->sdev; - req = (struct usb_ctrlrequest *) urb->setup_packet; - value = le16_to_cpu(req->wValue); - index = le16_to_cpu(req->wIndex); + usbip_uinfo("reset_device %s\n", dev_name(&urb->dev->dev)); - usbip_uinfo("reset_device (port %d) to %s\n", index, - dev_name(&urb->dev->dev)); - - /* 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"); - - 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; } /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/