From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752517AbdJ0S7n (ORCPT ); Fri, 27 Oct 2017 14:59:43 -0400 Received: from mail-dm3nam03on0054.outbound.protection.outlook.com ([104.47.41.54]:37753 "EHLO NAM03-DM3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751145AbdJ0S7l (ORCPT ); Fri, 27 Oct 2017 14:59:41 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=David.Daney@cavium.com; Subject: Re: [PATCH] init/main.c: check for null pointer before calling initcall To: Abderrahmane Benbachir Cc: Thomas Gleixner , linux-kernel@vger.kernel.org, mingo@kernel.org, akpm@linux-foundation.org, keescook@chromium.org, jeyu@redhat.com, rostedt@goodmis.org, mhocko@suse.com, viresh.kumar@linaro.org, thomas.lendacky@amd.com References: <1509122847.11787.5.camel@polymtl.ca> <7fc6e471-3ff9-83ea-f0c8-638959395494@caviumnetworks.com> <20171027185340.Horde.lrfWRcBHRmhKk906QJGixBF@www.imp.polymtl.ca> From: David Daney Message-ID: <72740265-1ea2-ad28-e4e7-518d13e0b4e2@caviumnetworks.com> Date: Fri, 27 Oct 2017 11:59:35 -0700 User-Agent: Mozilla/5.0 (X11; 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>>> >>> might do that, but then it rightfully crashes on boot. >>> >> >> That was kind of my point.  The module loader case already checks for >> a non-NULL pointer, and any NULLs in the in-kernel initializer tables >> would indicate a bigger problem that should be fixed instead. >> >> David Daney > > But this code can still be written : > > static initcall_t __initcall_mymod \ >    __used __section(".initcall6.init") = NULL; > > In fact, I'm using the code below to assign at runtime (dynamically) which > function to be executed or not. > Just use the standard initcall macros pointing to real functions. If you want to do something tricky, put it in your own init function, and don't mess with the core kernel code that has been working fine for decades. David Daney