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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE155E810A2 for ; Wed, 27 Sep 2023 08:24:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229527AbjI0IYh (ORCPT ); Wed, 27 Sep 2023 04:24:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230097AbjI0IYg (ORCPT ); Wed, 27 Sep 2023 04:24:36 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4120C116 for ; Wed, 27 Sep 2023 01:24:35 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2CED5C433C7; Wed, 27 Sep 2023 08:24:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695803074; bh=xh54gg2SSmqDr88p/sblGPHAUNEGvufvqce+W6sJzGE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JKoHPSnVdJ2nmKSINSeafaCDSIZt1bC5mElBagpM6jnnRVB4gDcBdMUqltSPY1mwP bHwiyqDkyRvr3HIoEG9FjOJa4DOa+joJWK4hgoR4uoPskk3H9G6YmNGzf/U2Ad5OsX 2wMcu4wC7KAXbwkUT4xeLL54rGr+IX5280DkCL0w= Date: Wed, 27 Sep 2023 10:24:31 +0200 From: Greg Kroah-Hartman To: "yiyang (D)" Cc: Jiri Slaby , hedonistsmith@gmail.com, daniel.starke@siemens.com, linux-serial Subject: Re: BUG: sleeping function called from invalid context in console_lock Message-ID: <2023092703-parrot-bobbed-d5d2@gregkh> References: <42c2c0c4-9ee2-6426-8c3c-2585e0345fcb@huawei.com> <2023091838-shrubs-paragraph-e579@gregkh> <9613ee6f-08f7-ab6e-64f0-38505f67b891@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9613ee6f-08f7-ab6e-64f0-38505f67b891@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Wed, Sep 27, 2023 at 03:48:33PM +0800, yiyang (D) wrote: > On 2023/9/18 23:19, Greg Kroah-Hartman wrote: > > On Mon, Sep 18, 2023 at 09:35:23PM +0800, yiyang (D) wrote: > > > In recent years, this problem has been reported in syzkaller all the time. > > > > > > Link: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c > > > > > > Historically, the developers have tried to fix this problem by use mutex > > > instead spinlock, but it didn't solve the problem.. > > > > > > Link: https://lore.kernel.org/all/20220826193545.20363-1-pchelkin@ispras.ru/ > > > > > > Other developers have recently reported this problem, but no one has > > > continued to try to fix it. > > > > > > Link: > > > https://lore.kernel.org/all/20230420082153.6711-1-daniel.starke@siemens.com/ > > > > > > Anyway, do we have any ideas for solving this problem? > > > > Nope! Why do you think this is something that even needs to be > > addressed? > > . > > > Kernel only perform cannot sleep operations in atomic context, as otherwise > a system hang or crash may occur. > > So there's a risk to this problem. > Have you see this risk in real workloads? If so, great, please provide a working solution that is tested and verified to work properly. good luck! greg k-h