From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754074AbdIFXFz (ORCPT ); Wed, 6 Sep 2017 19:05:55 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59101 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751153AbdIFXFy (ORCPT ); Wed, 6 Sep 2017 19:05:54 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 67FD7883A5 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jpoimboe@redhat.com Date: Wed, 6 Sep 2017 18:05:47 -0500 From: Josh Poimboeuf To: Miguel Bernal Marin Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , "H . Peter Anvin" , linux-kernel@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 0/3] locking/rwsem/x86: Add stack frame dependency for some inline asm Message-ID: <20170906230547.mgwjx74m6g7fntif@treble> References: <20170906052613.30058-1-miguel.bernal.marin@linux.intel.com> <20170906224501.11816-1-miguel.bernal.marin@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170906224501.11816-1-miguel.bernal.marin@linux.intel.com> User-Agent: Mutt/1.6.0.1 (2016-04-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 06 Sep 2017 23:05:54 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 06, 2017 at 05:44:58PM -0500, Miguel Bernal Marin wrote: > Some warning were showed by objtool using gcc 7.2.0 > > kernel/locking/rwsem.o: warning: objtool: up_read()+0x11: call without frame pointer save/setup > kernel/locking/rwsem.o: warning: objtool: up_write()+0x17: call without frame pointer save/setup > kernel/locking/rwsem.o: warning: objtool: downgrade_write()+0x22: call without frame pointer save/setup > > which means gcc placed an inline asm function and its call instruction before > the frame pointer setup. > > This series forces a stack frame to be created before the call instruction > by listing the stack pointer as an output operand in the inline asm statement. > > Changes in v2: > - Update first parameter from _ASM_ADD to '%3' at __downgrade_write() > > Miguel Bernal Marin (3): > locking/rwsem/x86: Add stack frame dependency for __up_read() > locking/rwsem/x86: Add stack frame dependency for __up_write() > locking/rwsem/x86: Add stack frame dependency for __downgrade_write() > > arch/x86/include/asm/rwsem.h | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) For the series: Reviewed-by: Josh Poimboeuf -- Josh