From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mtagate7.de.ibm.com (mtagate7.de.ibm.com [195.212.29.156]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mtagate7.de.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 96BC4DDF3A for ; Sat, 10 Mar 2007 20:58:17 +1100 (EST) Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate7.de.ibm.com (8.13.8/8.13.8) with ESMTP id l2A9wCGF127782 for ; Sat, 10 Mar 2007 09:58:12 GMT Received: from d12av01.megacenter.de.ibm.com (d12av01.megacenter.de.ibm.com [9.149.165.212]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l2A9wC4f2129946 for ; Sat, 10 Mar 2007 10:58:12 +0100 Received: from d12av01.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av01.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l2A9wBNa008989 for ; Sat, 10 Mar 2007 10:58:12 +0100 Subject: Re: [PATCH] Complain about missing system calls. From: Martin Schwidefsky To: Andi Kleen In-Reply-To: <20070309190051.GA20521@one.firstfloor.org> References: <1173394873.3461.510.camel@pmac.infradead.org> <20070309163805.GV18564@lug-owl.de> <20070309190051.GA20521@one.firstfloor.org> Content-Type: text/plain; charset=ISO-8859-1 Date: Sat, 10 Mar 2007 10:58:13 +0100 Message-Id: <1173520693.7128.17.camel@localhost> Mime-Version: 1.0 Cc: akpm@osdl.org, linux-arch@vger.kernel.org, sam@ravnborg.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, David Woodhouse , rmk@arm.linux.org.uk Reply-To: schwidefsky@de.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 2007-03-09 at 20:00 +0100, Andi Kleen wrote: > > Not everybody has a simple indexed list of pointers :) For example, > > for vax-linux, we use a struct per syscall with the expected number of > > on-stack longwords for the call. > > > > So if something "new" is coming up, please keep in mind that it should > > be flexible enough to represent that. :) > > Are there plans to merge vax any time soon to mainline? > > Normally we don't care very much about out of tree code, especially > if it adds complexity like this. > > But I suspect s390 would need number of arguments anyways. I can't quite follow that line of thought. Why does s390 need the number of arguments? The wrapper of a compat system call implicitly knows how many arguments a system calls to do the conversion. For a normal system call we just call the function. Random example sys_read: the user space loads the arguments to register %r2, %r3, %r4 and calls the system. The register are not touched until sys_read is reached. Only sys_read cares about the number of arguments in this case. -- blue skies, IBM Deutschland Entwicklung GmbH Martin Vorsitzender des Aufsichtsrats: Johann Weihen Geschäftsführung: Herbert Kircher Martin Schwidefsky Sitz der Gesellschaft: Böblingen Linux on zSeries Registergericht: Amtsgericht Stuttgart, Development HRB 243294 "Reality continues to ruin my life." - Calvin.