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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C5354C433ED for ; Tue, 11 May 2021 08:11:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 87C8B61075 for ; Tue, 11 May 2021 08:11:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230070AbhEKIMu (ORCPT ); Tue, 11 May 2021 04:12:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:59790 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229935AbhEKIMt (ORCPT ); Tue, 11 May 2021 04:12:49 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1620720703; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TWVXvnrJGKcCzxRqtOT1Qny8f0lpOip9d8xcmIIBgT4=; b=O1ndLASEpv7+JfgleJE6evX03cdjzjgRGWYcFD4mJUMMIymTXc7ckOE1wDE5pmyfMLHr6S WvCeeDiSd1pQz5Kzrl/Dx12NWFghL6l1gGfcQ7uHCvkZokaJZKCyUjbgTv5gk4cPg5f/O9 gveSWuqqcPFdzoQkTwsr0YrL8oy1gDI= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 06E74ABF6; Tue, 11 May 2021 08:11:43 +0000 (UTC) Message-ID: <795e587aa6f956f92064e57445d3d527ad87460b.camel@suse.com> Subject: Re: [PATCH] USB: cdc-wdm: Fix ODEBUG bug in wdm_disconnect From: Oliver Neukum To: Tetsuo Handa , qiang.zhang@windriver.com, gregkh@linuxfoundation.org, lee.jones@linaro.org Cc: linux-usb@vger.kernel.org Date: Tue, 11 May 2021 10:11:41 +0200 In-Reply-To: <0e4131c7-0372-53cb-74a3-13d3a58ba25c@i-love.sakura.ne.jp> References: <20210511033140.29658-1-qiang.zhang@windriver.com> <0e4131c7-0372-53cb-74a3-13d3a58ba25c@i-love.sakura.ne.jp> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Am Dienstag, den 11.05.2021, 14:48 +0900 schrieb Tetsuo Handa: > On 2021/05/11 12:31, qiang.zhang@windriver.com wrote: > > This warning is generated because when kfree wdm_device, > > it is found that there is still an active work in workqueue, > > This phenomenon may be due to the following reasons. > > when the devices disconnect, although the work was cancelled, > > but the schedule_work still may be called, therefore, before > > scheduling work, we need to detect the status of the device. > > > > Reported-by: syzbot < > > syzbot+7da71853830ac3289474@syzkaller.appspotmail.com> > > Signed-off-by: Zqiang > > --- > > drivers/usb/class/cdc-wdm.c | 13 ++++++++----- > > 1 file changed, 8 insertions(+), 5 deletions(-) > > > > Oliver Neukum is aware of this problem, and is considering poisoning > approach than > checking WDM_SUSPENDING/WDM_RESETTING/WDM_DISCONNECTING approach. I > guess we could > replace three test_bit() tests into OR'ed-bits test (something like > test_bits()) ? > > > https://lkml.kernel.org/r/2db36d52015b644cc1891fcffc87ef09c2b728b7.camel@suse.com > > Oliver, how do we want to fix this problem? Hi, I was under the assumption that Greg had already merged the fix 18abf874367456540846319574864e6ff32752e2 Am I wrong? Regards Oliver