From patchwork Sun Aug 30 15:04:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guenter Roeck X-Patchwork-Id: 11745191 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8380F1709 for ; Sun, 30 Aug 2020 15:05:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A04D20720 for ; Sun, 30 Aug 2020 15:05:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="h8YR4hed" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727077AbgH3PFx (ORCPT ); Sun, 30 Aug 2020 11:05:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54286 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726388AbgH3PEv (ORCPT ); Sun, 30 Aug 2020 11:04:51 -0400 Received: from mail-oi1-x242.google.com (mail-oi1-x242.google.com [IPv6:2607:f8b0:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1FE3C061573; Sun, 30 Aug 2020 08:04:50 -0700 (PDT) Received: by mail-oi1-x242.google.com with SMTP id j7so4986886oij.9; Sun, 30 Aug 2020 08:04:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=OYzNNlQnqbfdrR5BIEiLRBleJJxXkTs1ZX+qGsGLh84=; b=h8YR4hedSi8kp7nYNZN7j/BPhMClAEoyXxVj33nY231jl6DtXzhAWk52ftw1kGvj4H l2TFZ0egurTwgfPeAXv4ySlV4KmK7W7TeY/2Yb+cQAJlERF63uPSGz5XDLUwK3S/mMMu 5Ud3oIHE6GTv3eKFqVTtE0Kmpq9ty2AYAg4qItPaf4kvYZZQv3r5gwqq5oHo0K3rgHBN suJz8sVzirqw6yBCJp1Nci0/suOKUYEAl0thM+5EN216NX6sbktHP5HWFV4LpIYvxvP5 mX0jNA/idyX6Paq8l6YtOW0v6NFQx5GPVP5lxjGn2IKI7awLa3DYZl6q6tMjVTm+8tM7 gBWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references; bh=OYzNNlQnqbfdrR5BIEiLRBleJJxXkTs1ZX+qGsGLh84=; b=INryj1UCUcIC8t7G4w4Gv/+77hLWXLapUAhkVe/s11/HHRL5RKAbthazPWpdf0QAe7 Q68KwyxP3uaDvf9iNm7VZ/SiJjqvt+EsRXLfQAdu9rpF9f0LFixpA+QBItSjExPyAq3I ntS/DsenK6AzWdSixbFqa3QmEqsDOMAgKLrvb3j+IZaiFO+Q/iQzIog2PkMpjwQyNOPD 0XVPkZH7qej6FSjjPFxUiBCP0e4mS2tjhiZLPuFCgNQlm3NZ60LnZmew+pq+iNMxTxu6 OUjicN++RqpKzzw4K62DusVHdfeA7tyUO3e0aw5ebn3JIp3e68YER0Wkfjs+Bs+4YTic tg9w== X-Gm-Message-State: AOAM530C99QwJKYcqdBLzpGlaRzmBn8jRRFlAAAgfveV3NU6rIc0v9jX iwqVeu6aRKtMNfwaMYHtVRk= X-Google-Smtp-Source: ABdhPJwOfWD7+aGHr0WUHi0M8wt0arY6aznSeE7vZseyiAI0QaYuT0UPhOeyhcOIY3epqg3aPohAVA== X-Received: by 2002:a05:6808:7c8:: with SMTP id f8mr1242699oij.119.1598799889315; Sun, 30 Aug 2020 08:04:49 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id q9sm882356ooe.33.2020.08.30.08.04.48 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 30 Aug 2020 08:04:48 -0700 (PDT) From: Guenter Roeck To: Laurent Pinchart Cc: Mauro Carvalho Chehab , Sakari Ailus , linux-uvc-devel@lists.sourceforge.net, linux-usb@vger.kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Guenter Roeck , Alan Stern , Hans Verkuil Subject: [PATCH 1/5] media: uvcvideo: Cancel async worker earlier Date: Sun, 30 Aug 2020 08:04:39 -0700 Message-Id: <20200830150443.167286-2-linux@roeck-us.net> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200830150443.167286-1-linux@roeck-us.net> References: <20200830150443.167286-1-linux@roeck-us.net> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org So far the asynchronous control worker was canceled only in uvc_ctrl_cleanup_device. This is much later than the call to uvc_disconnect. However, after the call to uvc_disconnect returns, there must be no more USB activity. This can result in all kinds of problems in the USB code. One observed example: URB ffff993e83d0bc00 submitted while active WARNING: CPU: 0 PID: 4046 at drivers/usb/core/urb.c:364 usb_submit_urb+0x4ba/0x55e Modules linked in: <...> CPU: 0 PID: 4046 Comm: kworker/0:35 Not tainted 4.19.139 #18 Hardware name: Google Phaser/Phaser, BIOS Google_Phaser.10952.0.0 08/09/2018 Workqueue: events uvc_ctrl_status_event_work [uvcvideo] RIP: 0010:usb_submit_urb+0x4ba/0x55e Code: <...> RSP: 0018:ffffb08d471ebde8 EFLAGS: 00010246 RAX: a6da85d923ea5d00 RBX: ffff993e71985928 RCX: 0000000000000000 RDX: ffff993f37a1de90 RSI: ffff993f37a153d0 RDI: ffff993f37a153d0 RBP: ffffb08d471ebe28 R08: 000000000000003b R09: 001424bf85822e96 R10: 0000001000000000 R11: ffffffff975a4398 R12: ffff993e83d0b000 R13: ffff993e83d0bc00 R14: 0000000000000000 R15: 00000000fffffff0 FS: 0000000000000000(0000) GS:ffff993f37a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000ec9c0000 CR3: 000000025b160000 CR4: 0000000000340ef0 Call Trace: uvc_ctrl_status_event_work+0xd6/0x107 [uvcvideo] process_one_work+0x19b/0x4c5 worker_thread+0x10d/0x286 kthread+0x138/0x140 ? process_one_work+0x4c5/0x4c5 ? kthread_associate_blkcg+0xc1/0xc1 ret_from_fork+0x1f/0x40 Introduce new function uvc_ctrl_stop_device() to cancel the worker and call it from uvc_unregister_video() to solve the problem. Cc: Laurent Pinchart Cc: Alan Stern Cc: Hans Verkuil Signed-off-by: Guenter Roeck --- drivers/media/usb/uvc/uvc_ctrl.c | 11 +++++++---- drivers/media/usb/uvc/uvc_driver.c | 1 + drivers/media/usb/uvc/uvcvideo.h | 1 + 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c index e399b9fad757..130c56e0063d 100644 --- a/drivers/media/usb/uvc/uvc_ctrl.c +++ b/drivers/media/usb/uvc/uvc_ctrl.c @@ -2340,14 +2340,17 @@ static void uvc_ctrl_cleanup_mappings(struct uvc_device *dev, } } -void uvc_ctrl_cleanup_device(struct uvc_device *dev) +void uvc_ctrl_stop_device(struct uvc_device *dev) { - struct uvc_entity *entity; - unsigned int i; - /* Can be uninitialized if we are aborting on probe error. */ if (dev->async_ctrl.work.func) cancel_work_sync(&dev->async_ctrl.work); +} + +void uvc_ctrl_cleanup_device(struct uvc_device *dev) +{ + struct uvc_entity *entity; + unsigned int i; /* Free controls and control mappings for all entities. */ list_for_each_entry(entity, &dev->entities, list) { diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 431d86e1c94b..bfba67a69185 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1952,6 +1952,7 @@ static void uvc_unregister_video(struct uvc_device *dev) } uvc_status_unregister(dev); + uvc_ctrl_stop_device(dev); if (dev->vdev.dev) v4l2_device_unregister(&dev->vdev); diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h index 6ab972c643e3..543afcd9fd26 100644 --- a/drivers/media/usb/uvc/uvcvideo.h +++ b/drivers/media/usb/uvc/uvcvideo.h @@ -830,6 +830,7 @@ int uvc_query_v4l2_menu(struct uvc_video_chain *chain, int uvc_ctrl_add_mapping(struct uvc_video_chain *chain, const struct uvc_control_mapping *mapping); int uvc_ctrl_init_device(struct uvc_device *dev); +void uvc_ctrl_stop_device(struct uvc_device *dev); void uvc_ctrl_cleanup_device(struct uvc_device *dev); int uvc_ctrl_restore_values(struct uvc_device *dev); bool uvc_ctrl_status_event(struct urb *urb, struct uvc_video_chain *chain,