From patchwork Mon Mar 30 11:55:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 11465387 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BBF4F1392 for ; Mon, 30 Mar 2020 11:56:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8DB1A20578 for ; Mon, 30 Mar 2020 11:56:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DB1A20578 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 230A96B0032; Mon, 30 Mar 2020 07:55:56 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id EEB806B006E; Mon, 30 Mar 2020 07:55:55 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D3F3F6B0037; Mon, 30 Mar 2020 07:55:55 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0030.hostedemail.com [216.40.44.30]) by kanga.kvack.org (Postfix) with ESMTP id 9FE636B006E for ; Mon, 30 Mar 2020 07:55:55 -0400 (EDT) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 7E32C181AD0A9 for ; Mon, 30 Mar 2020 11:55:55 +0000 (UTC) X-FDA: 76651874670.23.eyes95_33ae18558714c X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,vbabka@suse.cz,,RULES_HIT:30029:30030:30054,0,RBL:195.135.220.15:@suse.cz:.lbl8.mailshell.net-62.2.6.2 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: eyes95_33ae18558714c X-Filterd-Recvd-Size: 4718 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf28.hostedemail.com (Postfix) with ESMTP for ; Mon, 30 Mar 2020 11:55:55 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 96DB7ABC2; Mon, 30 Mar 2020 11:55:52 +0000 (UTC) From: Vlastimil Babka To: Luis Chamberlain , Kees Cook , Iurii Zaikin Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-mm@kvack.org, Ivan Teterevkov , Michal Hocko , David Rientjes , Matthew Wilcox , "Eric W . Biederman" , "Guilherme G . Piccoli" , Alexey Dobriyan , Thomas Gleixner , Greg Kroah-Hartman , Christian Brauner , Vlastimil Babka Subject: [PATCH 2/3] kernel/sysctl: support handling command line aliases Date: Mon, 30 Mar 2020 13:55:34 +0200 Message-Id: <20200330115535.3215-3-vbabka@suse.cz> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200330115535.3215-1-vbabka@suse.cz> References: <20200330115535.3215-1-vbabka@suse.cz> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: We can now handle sysctl parameters on kernel command line, but historically some parameters introduced their own command line equivalent, which we don't want to remove for compatibility reasons. We can however convert them to the generic infrastructure with a table translating the legacy command line parameters to their sysctl names, and removing the one-off param handlers. This patch adds the support and makes the first conversion to demonstrate it, on the (deprecated) numa_zonelist_order parameter. Signed-off-by: Vlastimil Babka Acked-by: Kees Cook Reviewed-by: Luis Chamberlain --- fs/proc/proc_sysctl.c | 48 ++++++++++++++++++++++++++++++++++++------- mm/page_alloc.c | 9 -------- 2 files changed, 41 insertions(+), 16 deletions(-) diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 653188c9c4c9..97eb0b552bf8 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -1727,6 +1727,37 @@ int __init proc_sys_init(void) return sysctl_init(); } +struct sysctl_alias { + const char *kernel_param; + const char *sysctl_param; +}; + +/* + * Historically some settings had both sysctl and a command line parameter. + * With the generic sysctl. parameter support, we can handle them at a single + * place and only keep the historical name for compatibility. This is not meant + * to add brand new aliases. When adding existing aliases, consider whether + * the possibly different moment of changing the value (e.g. from early_param + * to the moment do_sysctl_args() is called) is an issue for the specific + * parameter. + */ +static const struct sysctl_alias sysctl_aliases[] = { + {"numa_zonelist_order", "vm.numa_zonelist_order" }, + { } +}; + +static const char *sysctl_find_alias(char *param) +{ + const struct sysctl_alias *alias; + + for (alias = &sysctl_aliases[0]; alias->kernel_param != NULL; alias++) { + if (strcmp(alias->kernel_param, param) == 0) + return alias->sysctl_param; + } + + return NULL; +} + /* Set sysctl value passed on kernel command line. */ static int process_sysctl_arg(char *param, char *val, const char *unused, void *arg) @@ -1740,15 +1771,18 @@ static int process_sysctl_arg(char *param, char *val, loff_t pos = 0; ssize_t wret; - if (strncmp(param, "sysctl", sizeof("sysctl") - 1)) - return 0; - - param += sizeof("sysctl") - 1; + if (strncmp(param, "sysctl", sizeof("sysctl") - 1) == 0) { + param += sizeof("sysctl") - 1; - if (param[0] != '/' && param[0] != '.') - return 0; + if (param[0] != '/' && param[0] != '.') + return 0; - param++; + param++; + } else { + param = (char *) sysctl_find_alias(param); + if (!param) + return 0; + } if (!proc_mnt) { proc_fs_type = get_fs_type("proc"); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3c4eb750a199..de7a134b1b8a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5460,15 +5460,6 @@ static int __parse_numa_zonelist_order(char *s) return 0; } -static __init int setup_numa_zonelist_order(char *s) -{ - if (!s) - return 0; - - return __parse_numa_zonelist_order(s); -} -early_param("numa_zonelist_order", setup_numa_zonelist_order); - char numa_zonelist_order[] = "Node"; /*