From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A98096453 for ; Tue, 22 Mar 2022 21:40:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 750D6C340EC; Tue, 22 Mar 2022 21:40:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1647985232; bh=44P0kXBr6Wmm5QcJbLKop4jEJJGuQ/RbesnXVFSmoiY=; h=Date:To:From:In-Reply-To:Subject:From; b=ldaxHFRUbsSnpy2BiwtwXQ/D2hAujdDqKxyXk0I8KUR457FA17I9OpUP8VX2Ux3Rp +2iW+39RZ4ByD3ZirqehcBsaoQKZ1p90FFNwYJz0LzJIofiVYR/0AlfniR6HCIZsaY k+6QTzBPEWl7sfWhOze5KIPrzJUGm6WFICCEQRS8= Date: Tue, 22 Mar 2022 14:40:31 -0700 To: vdavydov.dev@gmail.com,roman.gushchin@linux.dev,mkoutny@suse.com,mhocko@kernel.org,i.zhbanov@omprussia.ru,hannes@cmpxchg.org,rdunlap@infradead.org,akpm@linux-foundation.org,patches@lists.linux.dev,linux-mm@kvack.org,mm-commits@vger.kernel.org,torvalds@linux-foundation.org,akpm@linux-foundation.org From: Andrew Morton In-Reply-To: <20220322143803.04a5e59a07e48284f196a2f9@linux-foundation.org> Subject: [patch 040/227] mm/memcontrol: return 1 from cgroup.memory __setup() handler Message-Id: <20220322214032.750D6C340EC@smtp.kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Randy Dunlap Subject: mm/memcontrol: return 1 from cgroup.memory __setup() handler __setup() handlers should return 1 if the command line option is handled and 0 if not (or maybe never return 0; it just pollutes init's environment). The only reason that this particular __setup handler does not pollute init's environment is that the setup string contains a '.', as in "cgroup.memory". This causes init/main.c::unknown_boottoption() to consider it to be an "Unused module parameter" and ignore it. (This is for parsing of loadable module parameters any time after kernel init.) Otherwise the string "cgroup.memory=whatever" would be added to init's environment strings. Instead of relying on this '.' quirk, just return 1 to indicate that the boot option has been handled. Note that there is no warning message if someone enters: cgroup.memory=anything_invalid Link: https://lkml.kernel.org/r/20220222005811.10672-1-rdunlap@infradead.org Fixes: f7e1cb6ec51b0 ("mm: memcontrol: account socket memory in unified hierarchy memory controller") Signed-off-by: Randy Dunlap Reported-by: Igor Zhbanov Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Reviewed-by: Michal Koutný Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Roman Gushchin Signed-off-by: Andrew Morton --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/memcontrol.c~mm-memcontrol-return-1-from-cgroupmemory-__setup-handler +++ a/mm/memcontrol.c @@ -7058,7 +7058,7 @@ static int __init cgroup_memory(char *s) if (!strcmp(token, "nokmem")) cgroup_memory_nokmem = true; } - return 0; + return 1; } __setup("cgroup.memory=", cgroup_memory); _