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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 58864C2D0E8 for ; Thu, 26 Mar 2020 13:39:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CA1220775 for ; Thu, 26 Mar 2020 13:39:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585229961; bh=jea/qgHJAyGW6iWFXmvupsFjst79mZBXkmaFhSc/Y5Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=0pCOrt1xF4f7i9aW3aCtPZR6I4n785kRJz00S78GLqiXlL2dSt17NarQh7FmcNdMB hyxVz57xTXabmin8RbXI17ZqqHuO/HKE2koJAA+vy6iLnCNhWgz5dz+A2IuvYdiQeK fAolG57JSYUoyKLnpBVaC0dOEZTjTPKO2MR68ekQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727706AbgCZNjU (ORCPT ); Thu, 26 Mar 2020 09:39:20 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:39313 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbgCZNjU (ORCPT ); Thu, 26 Mar 2020 09:39:20 -0400 Received: by mail-wr1-f68.google.com with SMTP id p10so7832473wrt.6; Thu, 26 Mar 2020 06:39:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=19Pztl4eD0UX0aRRYwPGEQuItPKM8kfOdpcItRtfgXE=; b=hRlHoyGy8kDiWVnPBKxURkaL2L6SV+ZOF7aFTlt6HAMDc4lpmQBa+Vb3s9p+CaVDJJ mTmkh/i+ZJKTMKxLxqQqUxLPxQ3YOtOt12C4E3nYIuDq8dxDcwkLYVP/y4QzNkQdGQ7V birRYr/08BDowOUnKTfBlrfZISo2lHnGVCwifT2fw+ATX2AlFEGqaeA9+VarjYIhgmG4 3d8Z7dzk5N6hl+bHXJ2tkfmUJFccEIClwFGv8JllbAC1ndAtuiTdGJsK4fpM6T1/JMBC kf1xyJ2Ujr/A7g3R4xzHdF7CoY8skKzdux23/pymFUWrPb5gSLjtOBsW0addwPRWhEnh 721w== X-Gm-Message-State: ANhLgQ0PLxRlofV487m4oD+F0sZa5gTTgwck316e/ObuZXydLBurdyL3 XB2aMZOHiqR2yjxD/MDZBjQ= X-Google-Smtp-Source: ADFU+vtk9zmWZvzCHwkqppRQIVeYZ6TTx2b4k3bygVqfm3s1Ky3k2UREkOWABI0nEj77sewyC1P8pw== X-Received: by 2002:a05:6000:100f:: with SMTP id a15mr9083191wrx.382.1585229958157; Thu, 26 Mar 2020 06:39:18 -0700 (PDT) Received: from localhost (ip-37-188-135-150.eurotel.cz. [37.188.135.150]) by smtp.gmail.com with ESMTPSA id 195sm3660380wmb.8.2020.03.26.06.39.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Mar 2020 06:39:17 -0700 (PDT) Date: Thu, 26 Mar 2020 14:39:15 +0100 From: Michal Hocko To: Christian Brauner Cc: "Eric W. Biederman" , Vlastimil Babka , Luis Chamberlain , Kees Cook , Iurii Zaikin , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-mm@kvack.org, Ivan Teterevkov , David Rientjes , Matthew Wilcox , "Guilherme G . Piccoli" Subject: Re: [RFC v2 1/2] kernel/sysctl: support setting sysctl parameters from kernel command line Message-ID: <20200326133915.GQ27965@dhcp22.suse.cz> References: <20200325120345.12946-1-vbabka@suse.cz> <874kuc5b5z.fsf@x220.int.ebiederm.org> <20200326065829.GC27965@dhcp22.suse.cz> <20200326133041.a3zit3gzdqmphane@wittgenstein> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200326133041.a3zit3gzdqmphane@wittgenstein> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 26-03-20 14:30:41, Christian Brauner wrote: > On Thu, Mar 26, 2020 at 07:58:29AM +0100, Michal Hocko wrote: > > On Wed 25-03-20 17:20:40, Eric W. Biederman wrote: > > > Vlastimil Babka writes: > > [...] > > > > + if (strncmp(param, "sysctl.", sizeof("sysctl.") - 1)) > > > > + return 0; > > > > > > Is there any way we can use a slash separated path. I know > > > in practice there are not any sysctl names that don't have > > > a '.' in them but why should we artifically limit ourselves? > > > > Because this is the normal userspace interface? Why should it be any > > different from calling sysctl? > > [...] > > Imho, we should use ".". Kernel developers aren't the ones setting > these options, admins are and if I think back to the times doing that as > a job at uni I'd be very confused if I learned that I get to set sysctl > options through the kernel command but need to use yet another format > than what I usually do to set those from the shell. Consistency is most > of the times to be preferred imho. Absolutely agreed! Even if sysctl can consume / instead of ., which was a news to me btw, the majority of the usage is with `.' -- Michal Hocko SUSE Labs