From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754019Ab3BDALJ (ORCPT <rfc822;w@1wt.eu>);
	Sun, 3 Feb 2013 19:11:09 -0500
Received: from zeniv.linux.org.uk ([195.92.253.2]:36993 "EHLO
	ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751894Ab3BDALH (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Sun, 3 Feb 2013 19:11:07 -0500
Date: Mon, 4 Feb 2013 00:10:55 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Matthias Brugger <matthias.bgg@gmail.com>,
        Haavard Skinnemoen <hskinnemoen@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        David Howells <dhowells@redhat.com>, Dave Jones <davej@redhat.com>,
        Will Deacon <will.deacon@arm.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] arch: avr32: add dummy syscalls
Message-ID: <20130204001055.GV4503@ZenIV.linux.org.uk>
References: <1359291015-4544-1-git-send-email-matthias.bgg@gmail.com>
 <20130127195714.GA11224@samfundet.no>
 <20130127203009.GG4503@ZenIV.linux.org.uk>
 <20130127203954.GA22063@samfundet.no>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20130127203954.GA22063@samfundet.no>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sun, Jan 27, 2013 at 09:39:54PM +0100, Hans-Christian Egtvedt wrote:
> > If you are OK with going that way, I could probably put together patches doing
> > just that.  Note that for rt_sigsuspend/rt_sigreturn/sigaltstack the wrappers
> > are not needed at all - they can just use current_pt_regs() in syscall body.
> > IOW, all of syscall-stubs.S could be killed.
> 
> Nice, could you put together the preprocessor stuff in a patch? It would be
> great to not having to write a re-occuring stub for each syscall that has 6+
> arguments.
> 
> Thanks for looking at this.

Apologies about the delay...  One question: what's the AVR32 C ABI for
passing 64bit arguments?  The tricky bugger is sys_sync_file_range();
it takes (s32, s64, s64, u32) as arguments and if not any pair of
registers can be used to pass 64bit value, we have more serious trouble
there...