From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754660AbbG0UlJ (ORCPT ); Mon, 27 Jul 2015 16:41:09 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:37327 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752718AbbG0UlH (ORCPT ); Mon, 27 Jul 2015 16:41:07 -0400 Date: Mon, 27 Jul 2015 13:41:04 -0700 From: Guenter Roeck To: Paul Burton Cc: Ralf Baechle , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org Subject: Re: Crash in -next due to 'MIPS: Move FP usage checks into protected_{save, restore}_fp_context' Message-ID: <20150727204104.GA1198@roeck-us.net> References: <20150715160918.GA27653@roeck-us.net> <20150727150652.GA1756@roeck-us.net> <20150727172142.GE7289@NP-P-BURTON> <20150727174622.GA10708@roeck-us.net> <20150727180442.GG7289@NP-P-BURTON> <20150727194401.GC14674@roeck-us.net> <20150727200214.GH7289@NP-P-BURTON> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150727200214.GH7289@NP-P-BURTON> User-Agent: Mutt/1.5.23 (2014-03-12) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Paul, On Mon, Jul 27, 2015 at 01:02:14PM -0700, Paul Burton wrote: > > Hi Guenter, > > I'm currently mailing out v2 of the series which should fix your > problem. It was an issue where the kernel would check the FP context for > whether a SIGFPE should be generated even in cases where FP had not been > used by userland, and thus had not been initialised. My userland is > hard float & thus makes use of the FPU early whilst I believe yours is > soft float, which explains the difference in behaviour. > > I think the endian difference probably boils down to what garbage the > initial FP context contained. > Thanks a lot for the fix! Guenter