Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751805AbaBGQlK (ORCPT ); Fri, 7 Feb 2014 11:41:10 -0500 Received: from mail-ve0-f180.google.com ([209.85.128.180]:48900 "EHLO mail-ve0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751674AbaBGQlH (ORCPT ); Fri, 7 Feb 2014 11:41:07 -0500 MIME-Version: 1.0 In-Reply-To: References: From: Andy Lutomirski Date: Fri, 7 Feb 2014 08:40:45 -0800 Message-ID: Subject: Re: [ARCH question] Do syscall_get_nr and syscall_get_arguments always work? To: Jonas Bonn Cc: Oleg Nesterov , linux-arch , linux-audit@redhat.com, "linux-kernel@vger.kernel.org" , Andi Kleen , Steve Grubb , Eric Paris Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 7, 2014 at 4:58 AM, Jonas Bonn wrote: > Hi Andy, > > On 5 February 2014 00:50, Andy Lutomirski wrote: >> >> I can't even find the system call entry point on mips. >> >> >> Is there a semi-official answer here? > > I don't have an official answer for you, but when I wanted to do > something with these entry points a couple of years back I discovered > that they aren't very thoroughly implemented across the various > architectures. I started cleaning this up and can probably dig up > some of this for you if you need it. The syscall_get_xyz functions are certainly implemented and functional in all relevant architectures -- the audit code is already using them. The thing I'm uncertain about is whether they are usable with no syscall slow path bits set. I guess that, if the syscall restart logic needs to read the argument registers, then they're probably reliably saved... --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/