Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757326AbaD3FT4 (ORCPT ); Wed, 30 Apr 2014 01:19:56 -0400 Received: from terminus.zytor.com ([198.137.202.10]:45692 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751822AbaD3FTx (ORCPT ); Wed, 30 Apr 2014 01:19:53 -0400 Message-ID: <536087D5.1040409@zytor.com> Date: Tue, 29 Apr 2014 22:19:17 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: behanw@converseincode.com, viro@zeniv.linux.org.uk CC: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, dwmw2@infradead.org, Mark Charlebois Subject: Re: [PATCH] mbcache: LLVMLinux: Remove double calculation from mbcache References: <1398820239-1890-1-git-send-email-behanw@converseincode.com> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/29/2014 06:13 PM, H. Peter Anvin wrote: > I suspect this will generate FP instructions on x86 which will corrupt user space state. This is thus a critical bug!! It looks like at least x86-64 gcc does the evaluation at compile time and there aren't any fp instructions left in the code. However, it should still be fixed. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/