From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id 226646B016A for ; Mon, 22 Aug 2011 16:18:02 -0400 (EDT) Message-ID: <4E52B96B.8040404@zytor.com> Date: Mon, 22 Aug 2011 13:17:47 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: [RFC] x86, mm: start mmap allocation for libs from low addresses References: <20110812102954.GA3496@albatros> <20110816090540.GA7857@albatros> <20110822101730.GA3346@albatros> <4E5290D6.5050406@zytor.com> <20110822201418.GA3176@albatros> In-Reply-To: <20110822201418.GA3176@albatros> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Vasiliy Kulikov Cc: Thomas Gleixner , Ingo Molnar , kernel-hardening@lists.openwall.com, Peter Zijlstra , Andrew Morton , x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org On 08/22/2011 01:14 PM, Vasiliy Kulikov wrote: > >> Code-wise: >> >> The code is horrific; it is full of open-coded magic numbers; > > Agreed, the magic needs macro definition and comments. > >> it also >> puts a function called arch_get_unmapped_exec_area() in a generic file, >> which could best be described as "WTF" -- the arch_ prefix we use >> specifically to denote a per-architecture hook function. > > Agreed. But I'd want to leave it in mm/mmap.c as it's likely be used by > other archs - the changes are bitness specific, not arch specific. Is > it OK if I do this? > > #ifndef HAVE_ARCH_UNMAPPED_EXEC_AREA > void *arch_get_unmapped_exec_area(...) > { > ... > } > #endif > Only if this is really an architecture-specific function overridden in specific architectures. I'm not so sure that applies here. Furthermore, I'm not even all that sure what this function *does*. -hpa -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org