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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id D8B9BC5CFF1 for ; Tue, 12 Jun 2018 06:31:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97E6820660 for ; Tue, 12 Jun 2018 06:31:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 97E6820660 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de 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 S932916AbeFLGbP (ORCPT ); Tue, 12 Jun 2018 02:31:15 -0400 Received: from mx2.suse.de ([195.135.220.15]:55079 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753970AbeFLGbK (ORCPT ); Tue, 12 Jun 2018 02:31:10 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext-too.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 5CD3FAEBF; Tue, 12 Jun 2018 06:31:09 +0000 (UTC) Date: Tue, 12 Jun 2018 08:31:09 +0200 Message-ID: From: Takashi Iwai To: Waiman Long Cc: Andrew Morton , Davidlohr Bueso , linux-kernel@vger.kernel.org Subject: Re: [PATCH] ipc: Limit sysctl value to IPCMNI In-Reply-To: <46a299ce-072c-fc84-3d52-3179ee42db4a@redhat.com> References: <20180608134949.12672-1-tiwai@suse.de> <20180608141659.8a517b128c756b4d0b813c9e@linux-foundation.org> <46a299ce-072c-fc84-3d52-3179ee42db4a@redhat.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Jun 2018 23:27:08 +0200, Waiman Long wrote: > > On 06/08/2018 05:16 PM, Andrew Morton wrote: > > On Fri, 8 Jun 2018 15:49:49 +0200 Takashi Iwai wrote: > > > >> Currently shmmni proc entry accepts all entered integer values, but > >> the practical limit is IPCMNI (32768). This confuses user as if a > >> bigger value were accepted but not applied correctly. > >> > >> This patch changes the proc entry to use *_minmax variant to limit the > >> accepted values accordingly. > > Waiman Long was working on a (vastly more complicated) patchset to > > address this. > > > >> --- a/ipc/ipc_sysctl.c > >> +++ b/ipc/ipc_sysctl.c > >> @@ -99,6 +99,7 @@ static int proc_ipc_auto_msgmni(struct ctl_table *table, int write, > >> static int zero; > >> static int one = 1; > >> static int int_max = INT_MAX; > >> +static int ipcmni = IPCMNI; > >> > >> static struct ctl_table ipc_kern_table[] = { > >> { > >> @@ -120,7 +121,9 @@ static struct ctl_table ipc_kern_table[] = { > >> .data = &init_ipc_ns.shm_ctlmni, > >> .maxlen = sizeof(init_ipc_ns.shm_ctlmni), > >> .mode = 0644, > >> - .proc_handler = proc_ipc_dointvec, > >> + .proc_handler = proc_ipc_dointvec_minmax, > >> + .extra1 = &zero, > >> + .extra2 = &ipcmni, > >> }, > >> { > >> .procname = "shm_rmid_forced", > > What is the back-compatibility situation here? > > > > > Sorry for the late reply. I am planning to send out an updated patch > once the merge window is closed. The latest patch can be found in > > https://lkml.org/lkml/2018/5/7/666 > > Luis has some concern about the use of __read_mostly tag which I am > going to remove in the next version. Thanks, that's as trivial as my patch, unsurprisingly :) Takashi