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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 8A16EC46475 for ; Sat, 27 Oct 2018 03:36:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 384D92082C for ; Sat, 27 Oct 2018 03:36:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=thunk.org header.i=@thunk.org header.b="PykhxD1N" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 384D92082C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727741AbeJ0MPk (ORCPT ); Sat, 27 Oct 2018 08:15:40 -0400 Received: from imap.thunk.org ([74.207.234.97]:34388 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727417AbeJ0MPk (ORCPT ); Sat, 27 Oct 2018 08:15:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=thunk.org; s=ef5046eb; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=b/TxJuMdn3viuwjrsHaYqV136V/qHzY/u/OMsL9bjmg=; b=PykhxD1NLPkQ+9bUYbAmXQT70j TedClLhVy5JAkpsl9i2EeuvRojFlfWo+yRYtdMa0hWZ0eYUf5Z2GMjgq4X8VDsx658v8f3Aou8zks 0WMZABCr4fGGbs1wkMTcm1co1ggmKFUptbUg3Na30sIJyQJHQN5UXpAZXe1zvv0aM3uQ=; Received: from root (helo=callcc.thunk.org) by imap.thunk.org with local-esmtp (Exim 4.89) (envelope-from ) id 1gGFOD-0006BC-GJ; Sat, 27 Oct 2018 03:35:53 +0000 Received: by callcc.thunk.org (Postfix, from userid 15806) id 52E917A0147; Fri, 26 Oct 2018 23:35:52 -0400 (EDT) Date: Fri, 26 Oct 2018 23:35:52 -0400 From: "Theodore Y. Ts'o" To: Nick Desaulniers Cc: bvanassche@acm.org, Linus Torvalds , ooo@electrozaur.com, Nathan Chancellor , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org, LKML , hch@infradead.org Subject: Re: [PATCH] libosd: Remove ignored __weak attribute Message-ID: <20181027033552.GA29237@thunk.org> Mail-Followup-To: "Theodore Y. Ts'o" , Nick Desaulniers , bvanassche@acm.org, Linus Torvalds , ooo@electrozaur.com, Nathan Chancellor , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org, LKML , hch@infradead.org References: <20181025213144.GB24709@flashbox> <20181025225548.GA10326@flashbox> <1540576908.66186.103.camel@acm.org> <1540589437.66186.124.camel@acm.org> <1540591147.66186.127.camel@acm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 26, 2018 at 03:07:39PM -0700, Nick Desaulniers wrote: > > That's not completely correct. The standard approach to check whether or not > > a driver is still being used is to check its git history. If the number of > > contributors is low and it was several years ago that a new feature was added > > or a bug has been fixed it is likely that nobody is using that driver anymore. > > I don't disagree with you, I just don't see how what you state can be > reconciled with Linus' response in > https://lkml.org/lkml/2018/10/27/44. Those two viewpoints seem > incompatible to me, but maybe there's a nuance I'm missing? So a couple of observations. Obviously, drivers, file systems and architectures *have* been removed. It can be done; sometimes if it can be demonstrate that it can't possibly work (for example, due to bitrot, the kernel would immediately crashed if anyone tried to use the code in question :-). In other cases, drivers has been removed through the staging subsystem, sometimes by adding a "depends on BROKEN" in the Kconfig file, and seeing if anyone complains --- since removing a "depends on BROKEN" line in Kconfig is even easier than doing reverting a git commit (especially if the user downloaded a tarball instead of doing a git clone). If you've done your due diligence then the chances that you have to revert a change which disables and later removes the dead code can be pushed close to zero. The question is whether it's worth the effort. > Nathan and I are just pointing out a small fix to eliminate a small > warning, deleting all this code does kind of feels like "throwing out > the baby with the bath water." A nuclear option for what would be a > small change otherwise. Maybe it's good to discuss the EOL for > exofs/osd, but can we please decouple that conversation from the small > change Nathan and I are proposing? The second observation I'll make is that if someone is proposing a cleanup patch, it's unfair to dump on the person proposing the cleanup patch the (non-trivial) effort to drop a driver/file system/subsystem. If the maintainer wants to drop a driver/file system, that should be the maintainer's responsibiltiy; not someone proposing a cleanup/maintenance patch. - Ted