From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932612AbbGTOpf (ORCPT ); Mon, 20 Jul 2015 10:45:35 -0400 Received: from e06smtp13.uk.ibm.com ([195.75.94.109]:57901 "EHLO e06smtp13.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932561AbbGTOpc (ORCPT ); Mon, 20 Jul 2015 10:45:32 -0400 X-Helo: d06dlp02.portsmouth.uk.ibm.com X-MailFrom: heiko.carstens@de.ibm.com X-RcptTo: linux-s390@vger.kernel.org Date: Mon, 20 Jul 2015 16:45:13 +0200 From: Heiko Carstens To: Guenter Roeck Cc: Martin Schwidefsky , linux390@de.ibm.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar Subject: Re: [RFC PATCH] sched, s390: Fix the fallout of increasing the offset of 'thread_struct' within 'task_struct' Message-ID: <20150720144513.GD3607@osiris> References: <1437403315-31221-1-git-send-email-linux@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1437403315-31221-1-git-send-email-linux@roeck-us.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15072014-0013-0000-0000-000004C13883 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 20, 2015 at 07:41:55AM -0700, Guenter Roeck wrote: > Commit 0c8c0f03e3a2 ("x86/fpu, sched: Dynamically allocate 'struct fpu'") > moved the thread_struct to the bottom of task_struct. As a result, the > offset is now too large to be used in an immediate stfpc operation on s390, > resulting in the following compile error. > > arch/s390/kernel/traps.c: Assembler messages: > arch/s390/kernel/traps.c:262: Error: operand out of range > (0x00000000000023e8 is not between 0x0000000000000000 and 0x0000000000000fff) > arch/s390/kernel/traps.c:300: Error: operand out of range > (0x00000000000023e8 is not between 0x0000000000000000 and 0x0000000000000fff) > > Use a local variable to store fpc to solve the problem. > > Cc: Ingo Molnar > Signed-off-by: Guenter Roeck > --- > Compile tested only. > Wonder if storing fpc in current->thread.fp_regs.fpc is necessary. A proper patch is availabler here: https://git.kernel.org/cgit/linux/kernel/git/s390/linux.git/commit/?h=for-linus&id=3827ec3d8fd51aef8352b0282b14f0f3ab615930