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Biederman" , Nathan Chancellor , Geert Uytterhoeven , Maxime Coquelin , Alexandre Torgue , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Balbir Singh , Yang Yang , Peter Zijlstra , Juri Lelli , Vincent Guittot , Kees Cook , Joel Granados , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Shuah Khan , "Jason A. Donenfeld" , linux-kernel@vger.kernel.org Subject: Re: [PATCH -mm v2 1/1] sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 On 07/27, Nicolas Schier wrote: > > On Mon, Jul 27, 2026 at 04:47:22PM +0200, Oleg Nesterov wrote: > > > > -config PROC_SYSCTL > > +config SYSCTL > > bool "Sysctl support (/proc/sys)" if EXPERT > > depends on PROC_FS > > - select SYSCTL > > default y > > help > > The sysctl interface provides a means of dynamically changing > > Please be aware that renaming of Kconfig symbols may not be welcomed due > to unwanted effects for users and for bisecting, cp. last paragraph of You mean "Renaming config parameters is *bad*.". Yes, this was my concern too, please see below. > Personally, I do understand that it makes sense to clean this up, here. > As the default was and stays 'y' this should affect only "few" users, > but still I am feeling ambigious about it. > > Sorry for missing to point to that at the RFC. That is why the previous [RFC PATCH 1/1] killed the hidden SYSCTL, not PROC_SYSCTL. But that patch touched 170 files and the output from get_maintainer.pl was huge. >From [RFC PATCH 0/1]: Alternatively, we could kill CONFIG_PROC_SYSCTL in favour of CONFIG_SYSCTL. This would result in a much smaller patch, but I am not sure if it is "safe" because CONFIG_PROC_SYSCTL is user-visible in that it has a prompt in fs/proc/Kconfig. But perhaps this is fine? and after discussion with Eric we came to conclusion that "probably this is fine" in thic case. I do think it makes sense to cleanup the usage of PROC_SYSCTL/SYSCTL (kill one of them). Just look at kernel/pid.c. It defines the "static int proc_do_cad_pid()" if CONFIG_SYSCTL, but this function is only used if CONFIG_PROC_SYSCTL. This looks obviously wrong until you grep Kconfig's and realize that both are the same thing. Oleg.