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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 9C87DC388F7 for ; Tue, 3 Nov 2020 21:52:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40E5D207BB for ; Tue, 3 Nov 2020 21:52:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604440344; bh=6gqfKi7nRYV04QdamIXbFjjF4hzO7LFY2ItuIf0RGDY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ak8sXZ2SyaYMFdSzfWVf1ZayN2OGzHnvBKw+0ijrkdB/5SbUQ5fjBkmYamZXHlcae VaSVf5Ob2hPD+KcFPOc98CzKR05kY3E1CRl7mTbMNUT20DKktexc5HJcDpFp5sr6Dw S1s/tIeW1qX3utetGdmkzbV44M50r+hH9bpCJBVc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731321AbgKCUrS (ORCPT ); Tue, 3 Nov 2020 15:47:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:37360 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731269AbgKCUrO (ORCPT ); Tue, 3 Nov 2020 15:47:14 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B42C120719; Tue, 3 Nov 2020 20:47:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436433; bh=6gqfKi7nRYV04QdamIXbFjjF4hzO7LFY2ItuIf0RGDY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DyBS+mSw4dnpRRc6YKKMpK4BBtvTLffrjFnJEk3mBDU+mkMJsV8UBElvpQEaimOGf IBMByx08CYVZ2Vjy3eChL5HBQgvv4f/sVmzCUCuuERkuaJdsOYQDGFrSAyVwiLCeOh 34UdX7nhap/Jm8sF0uWqYeVVfzDJ+kTrwe6G/t3Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Neukum , Pascal Vizeli , Jerome Brunet Subject: [PATCH 5.9 248/391] usb: cdc-acm: fix cooldown mechanism Date: Tue, 3 Nov 2020 21:34:59 +0100 Message-Id: <20201103203403.746984686@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203348.153465465@linuxfoundation.org> References: <20201103203348.153465465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jerome Brunet commit 38203b8385bf6283537162bde7d499f830964711 upstream. Commit a4e7279cd1d1 ("cdc-acm: introduce a cool down") is causing regression if there is some USB error, such as -EPROTO. This has been reported on some samples of the Odroid-N2 using the Combee II Zibgee USB dongle. > struct acm *acm = container_of(work, struct acm, work) is incorrect in case of a delayed work and causes warnings, usually from the workqueue: > WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:1474 __queue_work+0x480/0x528. When this happens, USB eventually stops working completely after a while. Also the ACM_ERROR_DELAY bit is never set, so the cooldown mechanism previously introduced cannot be triggered and acm_submit_read_urb() is never called. This changes makes the cdc-acm driver use a single delayed work, fixing the pointer arithmetic in acm_softint() and set the ACM_ERROR_DELAY when the cooldown mechanism appear to be needed. Fixes: a4e7279cd1d1 ("cdc-acm: introduce a cool down") Cc: Oliver Neukum Reported-by: Pascal Vizeli Acked-by: Oliver Neukum Signed-off-by: Jerome Brunet Link: https://lore.kernel.org/r/20201019170702.150534-1-jbrunet@baylibre.com Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.c | 12 +++++------- drivers/usb/class/cdc-acm.h | 3 +-- 2 files changed, 6 insertions(+), 9 deletions(-) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -507,6 +507,7 @@ static void acm_read_bulk_callback(struc "%s - cooling babbling device\n", __func__); usb_mark_last_busy(acm->dev); set_bit(rb->index, &acm->urbs_in_error_delay); + set_bit(ACM_ERROR_DELAY, &acm->flags); cooldown = true; break; default: @@ -532,7 +533,7 @@ static void acm_read_bulk_callback(struc if (stopped || stalled || cooldown) { if (stalled) - schedule_work(&acm->work); + schedule_delayed_work(&acm->dwork, 0); else if (cooldown) schedule_delayed_work(&acm->dwork, HZ / 2); return; @@ -562,13 +563,13 @@ static void acm_write_bulk(struct urb *u acm_write_done(acm, wb); spin_unlock_irqrestore(&acm->write_lock, flags); set_bit(EVENT_TTY_WAKEUP, &acm->flags); - schedule_work(&acm->work); + schedule_delayed_work(&acm->dwork, 0); } static void acm_softint(struct work_struct *work) { int i; - struct acm *acm = container_of(work, struct acm, work); + struct acm *acm = container_of(work, struct acm, dwork.work); if (test_bit(EVENT_RX_STALL, &acm->flags)) { smp_mb(); /* against acm_suspend() */ @@ -584,7 +585,7 @@ static void acm_softint(struct work_stru if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) { for (i = 0; i < acm->rx_buflimit; i++) if (test_and_clear_bit(i, &acm->urbs_in_error_delay)) - acm_submit_read_urb(acm, i, GFP_NOIO); + acm_submit_read_urb(acm, i, GFP_KERNEL); } if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags)) @@ -1364,7 +1365,6 @@ made_compressed_probe: acm->ctrlsize = ctrlsize; acm->readsize = readsize; acm->rx_buflimit = num_rx_buf; - INIT_WORK(&acm->work, acm_softint); INIT_DELAYED_WORK(&acm->dwork, acm_softint); init_waitqueue_head(&acm->wioctl); spin_lock_init(&acm->write_lock); @@ -1574,7 +1574,6 @@ static void acm_disconnect(struct usb_in } acm_kill_urbs(acm); - cancel_work_sync(&acm->work); cancel_delayed_work_sync(&acm->dwork); tty_unregister_device(acm_tty_driver, acm->minor); @@ -1617,7 +1616,6 @@ static int acm_suspend(struct usb_interf return 0; acm_kill_urbs(acm); - cancel_work_sync(&acm->work); cancel_delayed_work_sync(&acm->dwork); acm->urbs_in_error_delay = 0; --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -112,8 +112,7 @@ struct acm { # define ACM_ERROR_DELAY 3 unsigned long urbs_in_error_delay; /* these need to be restarted after a delay */ struct usb_cdc_line_coding line; /* bits, stop, parity */ - struct work_struct work; /* work queue entry for various purposes*/ - struct delayed_work dwork; /* for cool downs needed in error recovery */ + struct delayed_work dwork; /* work queue entry for various purposes */ unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */ unsigned int ctrlout; /* output control lines (DTR, RTS) */ struct async_icount iocount; /* counters for control line changes */