From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0BAC0C43441 for ; Thu, 15 Nov 2018 17:14:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7BC52087A for ; Thu, 15 Nov 2018 17:14:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C7BC52087A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388564AbeKPDXE (ORCPT ); Thu, 15 Nov 2018 22:23:04 -0500 Received: from mx2.suse.de ([195.135.220.15]:40256 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2387839AbeKPDXE (ORCPT ); Thu, 15 Nov 2018 22:23:04 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E8A07AD98; Thu, 15 Nov 2018 17:14:22 +0000 (UTC) From: Nicolas Saenz Julienne To: nsaaenzjulienne@suse.de, linux-kernel@vger.kernel.org Cc: Nicolas Saenz Julienne , Greg Kroah-Hartman , linux-usb@vger.kernel.org Subject: [PATCH] usb: hub: add I/O error retry & reset routine Date: Thu, 15 Nov 2018 18:14:18 +0100 Message-Id: <20181115171418.23522-1-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org An URB submission error in the HUB's endpoint completion function renders the whole HUB device unresponsive. This patch introduces a routine that retries the submission for 1s to then, as a last resort, reset the whole device. The implementation is based on usbhid/hid_core.c's, which implements the same functionality. It was tested with the help of BCC's error injection tool (inject.py). Signed-off-by: Nicolas Saenz Julienne --- drivers/usb/core/hub.c | 43 +++++++++++++++++++++++++++++++++++++++++- drivers/usb/core/hub.h | 3 +++ 2 files changed, 45 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index d9bd7576786a..1447bdba59ec 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -607,6 +607,44 @@ static int hub_port_status(struct usb_hub *hub, int port1, status, change, NULL); } +static void hub_io_error(struct usb_hub *hub) +{ + /* + * If it has been a while since the last error, we'll assume + * this a brand new error and reset the retry timeout. + */ + if (time_after(jiffies, hub->stop_retry + HZ/2)) + hub->retry_delay = 0; + + /* When an error occurs, retry at increasing intervals */ + if (hub->retry_delay == 0) { + hub->retry_delay = 13; /* Then 26, 52, 104, 104, ... */ + hub->stop_retry = jiffies + msecs_to_jiffies(1000); + } else if (hub->retry_delay < 100) + hub->retry_delay *= 2; + + if (time_after(jiffies, hub->stop_retry)) { + /* Retries failed, so do a port reset */ + usb_queue_reset_device(to_usb_interface(hub->intfdev)); + return; + } + + mod_timer(&hub->io_retry, + jiffies + msecs_to_jiffies(hub->retry_delay)); +} + +static void hub_retry_timeout(struct timer_list *t) +{ + struct usb_hub *hub = from_timer(hub, t, io_retry); + + if (hub->disconnected || hub->quiescing) + return; + + dev_err(hub->intfdev, "retrying int urb\n"); + if (usb_submit_urb(hub->urb, GFP_ATOMIC)) + hub_io_error(hub); +} + static void kick_hub_wq(struct usb_hub *hub) { struct usb_interface *intf; @@ -713,8 +751,10 @@ static void hub_irq(struct urb *urb) return; status = usb_submit_urb(hub->urb, GFP_ATOMIC); - if (status != 0 && status != -ENODEV && status != -EPERM) + if (status != 0 && status != -ENODEV && status != -EPERM) { dev_err(hub->intfdev, "resubmit --> %d\n", status); + hub_io_error(hub); + } } /* USB 2.0 spec Section 11.24.2.3 */ @@ -1800,6 +1840,7 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) INIT_DELAYED_WORK(&hub->leds, led_work); INIT_DELAYED_WORK(&hub->init_work, NULL); INIT_WORK(&hub->events, hub_event); + timer_setup(&hub->io_retry, hub_retry_timeout, 0); usb_get_intf(intf); usb_get_dev(hdev); diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h index 4accfb63f7dc..7dbd19c2c8d9 100644 --- a/drivers/usb/core/hub.h +++ b/drivers/usb/core/hub.h @@ -69,6 +69,9 @@ struct usb_hub { struct delayed_work leds; struct delayed_work init_work; struct work_struct events; + struct timer_list io_retry; + unsigned long stop_retry; + unsigned int retry_delay; struct usb_port **ports; }; -- 2.19.1