Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754200AbcCJRP0 (ORCPT ); Thu, 10 Mar 2016 12:15:26 -0500 Received: from mail-wm0-f51.google.com ([74.125.82.51]:34819 "EHLO mail-wm0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752563AbcCJRPT (ORCPT ); Thu, 10 Mar 2016 12:15:19 -0500 Message-ID: <1457630115.5784.1.camel@nexus-software.ie> Subject: Re: Got FPU related warning on Intel Quark during boot From: "Bryan O'Donoghue" To: Borislav Petkov Cc: Andy Shevchenko , Ingo Molnar , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Andy Lutomirski , Fenghua Yu , Linus Torvalds , "H. Peter Anvin" , Thomas Gleixner , Andrew Morton , Dave Hansen , Oleg Nesterov , "Yu, Yu-cheng" Date: Thu, 10 Mar 2016 17:15:15 +0000 In-Reply-To: <20160310164924.GC26708@pd.tnic> References: <20160310111935.GB13102@gmail.com> <20160310125610.GA26708@pd.tnic> <20160310145940.GB26708@pd.tnic> <1457624721.5784.0.camel@nexus-software.ie> <20160310164924.GC26708@pd.tnic> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5-1ubuntu3.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 735 Lines: 23 On Thu, 2016-03-10 at 17:49 +0100, Borislav Petkov wrote: > On Thu, Mar 10, 2016 at 03:45:21PM +0000, Bryan O'Donoghue wrote: > > It works but user-space FPU is broken; something's wrong with the > > initial state of the FPU regs - it looks as though they aren't > > being > > properly initialized and FPU context in the signal handler is wrong > > too. > > What does your test prog say when you boot linux-next with > "eagerfpu=off" and *without* my fix? > root@galileo:~# ./fpu f is 10.000000 g is 10.100000 Double value is 0.000000 Double value is 0.100000 Double value is 0.200000 ^Chandler value of variable is 0.300000 Double value is 0.300000 Double value is 0.400000 ^Z [1]+ Stopped ./fpu root@galileo:~#