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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 46EFCC433B4 for ; Fri, 2 Apr 2021 07:54:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 136C5610FC for ; Fri, 2 Apr 2021 07:54:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233521AbhDBHyQ (ORCPT ); Fri, 2 Apr 2021 03:54:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:34096 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234217AbhDBHyQ (ORCPT ); Fri, 2 Apr 2021 03:54:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DAE4061103; Fri, 2 Apr 2021 07:54:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617350055; bh=rgAN5tZmvrtw+l6Z9MPiySclNGXhZ1o2U2MSPQYWr3g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ux+hbwzMDDMPpgMKWAK/ZdqlMjwjDKCk3k4nHlq7/vmtiMNbA39NNQiftujSoK6da ixoeeWGlZeFt20Ed1CpxsayE5/GIzcq0iYnn5bTASWKA4XMF366eKIcMHapf1aGU9I 002pWXurMeElpLaGHfYm1awf4b5JpcVR10+TDcuI= Date: Fri, 2 Apr 2021 09:54:12 +0200 From: Greg KH To: Luis Chamberlain Cc: Minchan Kim , keescook@chromium.org, dhowells@redhat.com, hch@infradead.org, mbenes@suse.com, ngupta@vflare.org, sergey.senozhatsky.work@gmail.com, axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] zram: fix crashes due to use of cpu hotplug multistate Message-ID: References: <20210310212128.GR4332@42.do-not-panic.com> <20210312183238.GW4332@42.do-not-panic.com> <20210319190924.GK4332@42.do-not-panic.com> <20210322204156.GM4332@42.do-not-panic.com> <20210401235925.GR4332@42.do-not-panic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210401235925.GR4332@42.do-not-panic.com> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Apr 01, 2021 at 11:59:25PM +0000, Luis Chamberlain wrote: > As for the syfs deadlock possible with drivers, this fixes it in a generic way: > > commit fac43d8025727a74f80a183cc5eb74ed902a5d14 > Author: Luis Chamberlain > Date: Sat Mar 27 14:58:15 2021 +0000 > > sysfs: add optional module_owner to attribute > > This is needed as otherwise the owner of the attribute > or group read/store might have a shared lock used on driver removal, > and deadlock if we race with driver removal. > > Signed-off-by: Luis Chamberlain No, please no. Module removal is a "best effort", if the system dies when it happens, that's on you. I am not willing to expend extra energy and maintance of core things like sysfs for stuff like this that does not matter in any system other than a developer's box. Lock data, not code please. Trying to tie data structure's lifespans to the lifespan of code is a tangled mess, and one that I do not want to add to in any form. sorry, greg k-h