From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtprelay0195.hostedemail.com ([216.40.44.195]:36075 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752486AbcF1Vu3 (ORCPT ); Tue, 28 Jun 2016 17:50:29 -0400 Message-ID: <1467150555.24287.77.camel@perches.com> Subject: Re: [PATCH v1 0/2] Introduce the initify gcc plugin From: Joe Perches Date: Tue, 28 Jun 2016 14:49:15 -0700 In-Reply-To: <20160628133407.10c2ea1ecd194e8085e84c5a@gmail.com> References: <20160628133407.10c2ea1ecd194e8085e84c5a@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Emese Revfy , kernel-hardening@lists.openwall.com, Matt Davis Cc: pageexec@freemail.hu, spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org, linux-kernel@vger.kernel.org, yamada.masahiro@socionext.com, linux-kbuild@vger.kernel.org, minipli@ld-linux.so, linux@armlinux.org.uk, catalin.marinas@arm.com, linux@rasmusvillemoes.dk, david.brown@linaro.org, benh@kernel.crashing.org, tglx@linutronix.de, akpm@linux-foundation.org, jlayton@poochiereds.net, arnd@arndb.de On Tue, 2016-06-28 at 13:34 +0200, Emese Revfy wrote: > I would like to introduce the initify gcc plugin. The kernel already has > a mechanism to free up code and data memory that is only used during kernel > or module initialization. > This plugin will teach the compiler to find more such code and data that > can be freed after initialization. It reduces memory usage. > The initify gcc plugin can be useful for embedded systems. Another potentially useful plugin, especially for embedded systems, would be to compress any string literal marked with  __attribute__((format(printf, string-index,))) and decompress the compressed format on the stack in lib/vsprintf.c vsnprintf just before use. I've started to experiment with that.