From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: x86-64: Maintain 16-byte stack alignment Date: Tue, 10 Jan 2017 09:05:28 -0800 Message-ID: References: <20170110143340.GA3787@gondor.apana.org.au> <20170110143913.GA3822@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Linux Kernel Mailing List , Linux Crypto Mailing List , Ingo Molnar , Thomas Gleixner , Andy Lutomirski , Ard Biesheuvel To: Herbert Xu Return-path: Received: from mail-it0-f66.google.com ([209.85.214.66]:36410 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757974AbdAJRFa (ORCPT ); Tue, 10 Jan 2017 12:05:30 -0500 In-Reply-To: <20170110143913.GA3822@gondor.apana.org.au> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Tue, Jan 10, 2017 at 6:39 AM, Herbert Xu wrote: > > BTW this is with Debian gcc 4.7.2 which does not allow an 8-byte > stack alignment as attempted by the Makefile: I'm pretty sure we have random asm code that may not maintain a 16-byte stack alignment when it calls other code (including, in some cases, calling C code). So I'm not at all convinced that this is a good idea. We shouldn't expect 16-byte alignment to be something trustworthy. Linus