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([2620:15c:2cd:203:5cdc:422c:7b28:ebb5]) by smtp.gmail.com with ESMTPSA id p1-v6sm16358816pfj.72.2018.10.26.14.59.08 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 26 Oct 2018 14:59:08 -0700 (PDT) Message-ID: <1540591147.66186.127.camel@acm.org> Subject: Re: [PATCH] libosd: Remove ignored __weak attribute From: Bart Van Assche To: Nick Desaulniers Cc: ooo@electrozaur.com, Nathan Chancellor , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org, LKML , hch@infradead.org Date: Fri, 26 Oct 2018 14:59:07 -0700 In-Reply-To: References: <20180930205448.26205-1-natechancellor@gmail.com> <10b12992-3570-4646-374b-82cbd7276839@acm.org> <1538503063.193396.6.camel@acm.org> <1538521591.193396.8.camel@acm.org> <20181025213144.GB24709@flashbox> <20181025225548.GA10326@flashbox> <1540576908.66186.103.camel@acm.org> <1540589437.66186.124.camel@acm.org> Content-Type: text/plain; charset="UTF-7" X-Mailer: Evolution 3.26.2-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2018-10-26 at 14:36 -0700, Nick Desaulniers wrote: +AD4 On Fri, Oct 26, 2018 at 2:30 PM Bart Van Assche +ADw-bvanassche+AEA-acm.org+AD4 wrote: +AD4 +AD4 +AD4 +AD4 On Fri, 2018-10-26 at 14:00 -0700, Nick Desaulniers wrote: +AD4 +AD4 +AD4 On Fri, Oct 26, 2018 at 11:01 AM Bart Van Assche +ADw-bvanassche+AEA-acm.org+AD4 wrote: +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 On Fri, 2018-10-26 at 10:54 -0700, Nick Desaulniers wrote: +AD4 +AD4 +AD4 +AD4 +AD4 If creating one instance of this variable is a functional change, I +AD4 +AD4 +AD4 +AD4 +AD4 can't help but suspect the original code was wrong. But maybe Bart, +AD4 +AD4 +AD4 +AD4 +AD4 Boaz, or Christoph can clarify or have more thoughts on this? Looks +AD4 +AD4 +AD4 +AD4 +AD4 like Boaz added this header in commit de258bf5e638 (+ACIAWw-SCSI+AF0 libosd: +AD4 +AD4 +AD4 +AD4 +AD4 OSDv1 Headers+ACI). +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 Hi Nick and Nathan, +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 Had you noticed the following e-mail from early October: +AD4 +AD4 +AD4 +AD4 https://marc.info/?l+AD0-linux-kernel+ACY-m+AD0-153849955503249? +AD4 +AD4 +AD4 +AD4 +AD4 +AD4 From this subthread with Linus, removal of the exofs fs and scsi osd +AD4 +AD4 +AD4 code would be a user visible change and is not an option. See: +AD4 +AD4 +AD4 https://lkml.org/lkml/2018/10/27/3 +AD4 +AD4 +AD4 https://lkml.org/lkml/2018/10/27/44 +AD4 +AD4 +AD4 +AD4 Hi Nick, +AD4 +AD4 +AD4 +AD4 Linus wrote that removing a filesystem is considered a userspace breakage +AD4 +AD4 if a user notices. The key part is +ACI-if a user notices+ACI. Who are the exofs +AD4 +AD4 users? +AD4 +AD4 See my thoughts on this in https://lkml.org/lkml/2018/10/27/27. +AD4 Particularly the part about the IMO catch 22. +AD4 +AD4 Neither you nor I can claim +ACI-there are none.+ACI 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. Bart.