From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757548AbYK0KxH (ORCPT ); Thu, 27 Nov 2008 05:53:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754833AbYK0Kd4 (ORCPT ); Thu, 27 Nov 2008 05:33:56 -0500 Received: from mtagate7.de.ibm.com ([195.212.29.156]:62897 "EHLO mtagate7.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753048AbYK0KcZ (ORCPT ); Thu, 27 Nov 2008 05:32:25 -0500 Message-Id: <20081127103136.719281319@de.ibm.com> References: <20081127103020.528516828@de.ibm.com> User-Agent: quilt/0.46-1 Date: Thu, 27 Nov 2008 11:30:52 +0100 From: Martin Schwidefsky To: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Cc: Heiko Carstens , Martin Schwidefsky Subject: [patch 32/60] Remove initial kernel stack backchain initialization. Content-Disposition: inline; filename=131-clear-backchain.diff Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Heiko Carstens Early init code clears the backchain of the initial kernel stack frame. This is not necessary since it is pre initialized with zeros. Plus it was broken on 64 bit since it cleared only four of eight bytes. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/head31.S | 1 - arch/s390/kernel/head64.S | 1 - 2 files changed, 2 deletions(-) Index: quilt-2.6/arch/s390/kernel/head31.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/head31.S +++ quilt-2.6/arch/s390/kernel/head31.S @@ -29,7 +29,6 @@ startup_continue: ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union+THREAD_SIZE st %r15,__LC_KERNEL_STACK # set end of kernel stack ahi %r15,-96 - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain # # Save ipl parameters, clear bss memory, initialize storage key for kernel pages, # and create a kernel NSS if the SAVESYS= parm is defined Index: quilt-2.6/arch/s390/kernel/head64.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/head64.S +++ quilt-2.6/arch/s390/kernel/head64.S @@ -96,7 +96,6 @@ startup_continue: aghi %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE stg %r15,__LC_KERNEL_STACK # set end of kernel stack aghi %r15,-160 - xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain # # Save ipl parameters, clear bss memory, initialize storage key for kernel pages, # and create a kernel NSS if the SAVESYS= parm is defined -- blue skies, Martin. "Reality continues to ruin my life." - Calvin.