From patchwork Sun Aug 11 05:11:10 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Young X-Patchwork-Id: 11088723 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BE5B61398 for ; Sun, 11 Aug 2019 05:11:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B083526E3C for ; Sun, 11 Aug 2019 05:11:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A49F727CEA; Sun, 11 Aug 2019 05:11:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B70E126E3C for ; Sun, 11 Aug 2019 05:11:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725861AbfHKFLN (ORCPT ); Sun, 11 Aug 2019 01:11:13 -0400 Received: from gofer.mess.org ([88.97.38.141]:35575 "EHLO gofer.mess.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725813AbfHKFLN (ORCPT ); Sun, 11 Aug 2019 01:11:13 -0400 Received: by gofer.mess.org (Postfix, from userid 1000) id 8DDA360A27; Sun, 11 Aug 2019 06:11:10 +0100 (BST) Date: Sun, 11 Aug 2019 06:11:10 +0100 From: Sean Young To: syzbot Cc: andreyknvl@google.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-usb@vger.kernel.org, mchehab@kernel.org, syzkaller-bugs@googlegroups.com Subject: [PATCH] media: em28xx: modules workqueue not inited for 2nd device Message-ID: <20190811051110.hsdwmjrbvqgrmssc@gofer.mess.org> References: <0000000000004bcc0d058faf01c4@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <0000000000004bcc0d058faf01c4@google.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP syzbot reports an error on flush_request_modules() for the second device. This workqueue was never initialised so simply remove the offending line. usb 1-1: USB disconnect, device number 2 em28xx 1-1:1.153: Disconnecting em28xx #1 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 12 at kernel/workqueue.c:3031 __flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.3.0-rc2+ #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 panic+0x2a3/0x6da kernel/panic.c:219 __warn.cold+0x20/0x4a kernel/panic.c:576 report_bug+0x262/0x2a0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026 RIP: 0010:__flush_work.cold+0x2c/0x36 kernel/workqueue.c:3031 Code: 9a 22 00 48 c7 c7 20 e4 c5 85 e8 d9 3a 0d 00 0f 0b 45 31 e4 e9 98 86 ff ff e8 51 9a 22 00 48 c7 c7 20 e4 c5 85 e8 be 3a 0d 00 <0f> 0b 45 31 e4 e9 7d 86 ff ff e8 36 9a 22 00 48 c7 c7 20 e4 c5 85 RSP: 0018:ffff8881da20f720 EFLAGS: 00010286 RAX: 0000000000000024 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed103b441ed6 RBP: ffff8881da20f888 R08: 0000000000000024 R09: fffffbfff11acd9a R10: fffffbfff11acd99 R11: ffffffff88d66ccf R12: 0000000000000000 R13: 0000000000000001 R14: ffff8881c6685df8 R15: ffff8881d2a85b78 flush_request_modules drivers/media/usb/em28xx/em28xx-cards.c:3325 [inline] em28xx_usb_disconnect.cold+0x280/0x2a6 drivers/media/usb/em28xx/em28xx-cards.c:4023 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1120 [inline] device_release_driver_internal+0x404/0x4c0 drivers/base/dd.c:1151 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:556 device_del+0x420/0xb10 drivers/base/core.c:2288 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199 hub_port_connect drivers/usb/core/hub.c:4949 [inline] hub_port_connect_change drivers/usb/core/hub.c:5213 [inline] port_event drivers/usb/core/hub.c:5359 [inline] hub_event+0x1454/0x3640 drivers/usb/core/hub.c:5441 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 process_scheduled_works kernel/workqueue.c:2331 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. Reported-by: syzbot+b7f57261c521087d89bb@syzkaller.appspotmail.com Signed-off-by: Sean Young Reviewed-by: Ezequiel Garcia Reviewed-by: Brad Love --- drivers/media/usb/em28xx/em28xx-cards.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c index 6e33782c3ca6..5983e72a0622 100644 --- a/drivers/media/usb/em28xx/em28xx-cards.c +++ b/drivers/media/usb/em28xx/em28xx-cards.c @@ -4019,7 +4019,6 @@ static void em28xx_usb_disconnect(struct usb_interface *intf) dev->dev_next->disconnected = 1; dev_info(&dev->intf->dev, "Disconnecting %s\n", dev->dev_next->name); - flush_request_modules(dev->dev_next); } dev->disconnected = 1;