From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67939C43387 for ; Thu, 10 Jan 2019 20:33:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C44920879 for ; Thu, 10 Jan 2019 20:33:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729355AbfAJUdM (ORCPT ); Thu, 10 Jan 2019 15:33:12 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:54470 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728195AbfAJUdL (ORCPT ); Thu, 10 Jan 2019 15:33:11 -0500 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id x0AKSutg134103 for ; Thu, 10 Jan 2019 15:33:09 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2px9yy0xgc-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 10 Jan 2019 15:33:09 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 10 Jan 2019 20:33:07 -0000 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 10 Jan 2019 20:32:57 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x0AKWunm27590674 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 10 Jan 2019 20:32:56 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 53D39AE055; Thu, 10 Jan 2019 20:32:56 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E9552AE051; Thu, 10 Jan 2019 20:32:54 +0000 (GMT) Received: from osiris (unknown [9.145.24.85]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Thu, 10 Jan 2019 20:32:54 +0000 (GMT) Date: Thu, 10 Jan 2019 21:32:53 +0100 From: Heiko Carstens To: Arnd Bergmann Cc: y2038@lists.linaro.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, ink@jurassic.park.msu.ru, mattst88@gmail.com, linux@armlinux.org.uk, catalin.marinas@arm.com, will.deacon@arm.com, tony.luck@intel.com, fenghua.yu@intel.com, geert@linux-m68k.org, monstr@monstr.eu, paul.burton@mips.com, deller@gmx.de, mpe@ellerman.id.au, schwidefsky@de.ibm.com, dalias@libc.org, davem@davemloft.net, luto@kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, jcmvbkbc@gmail.com, firoz.khan@linaro.org, ebiederm@xmission.com, deepa.kernel@gmail.com, linux@dominikbrodowski.net, akpm@linux-foundation.org, dave@stgolabs.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org Subject: Re: [PATCH 14/15] arch: add split IPC system calls where needed References: <20190110162435.309262-1-arnd@arndb.de> <20190110162435.309262-15-arnd@arndb.de> MIME-Version: 1.0 In-Reply-To: <20190110162435.309262-15-arnd@arndb.de> X-TM-AS-GCONF: 00 x-cbid: 19011020-0020-0000-0000-000003049552 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19011020-0021-0000-0000-000021559AEC Message-Id: <20190110203253.GA3676@osiris> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit Content-Disposition: inline X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-01-10_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=753 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1901100158 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 10, 2019 at 05:24:34PM +0100, Arnd Bergmann wrote: > The IPC system call handling is highly inconsistent across architectures, > some use sys_ipc, some use separate calls, and some use both. We also > have some architectures that require passing IPC_64 in the flags, and > others that set it implicitly. > > For the additon of a y2083 safe semtimedop() system call, I chose to only > support the separate entry points, but that requires first supporting > the regular ones with their own syscall numbers. > > The IPC_64 is now implied by the new semctl/shmctl/msgctl system > calls even on the architectures that require passing it with the ipc() > multiplexer. > > I'm not adding the new semtimedop() or semop() on 32-bit architectures, > those will get implemented using the new semtimedop_time64() version > that gets added along with the other time64 calls. > Three 64-bit architectures (powerpc, s390 and sparc) get semtimedop(). > > Signed-off-by: Arnd Bergmann > --- > One aspect here that might be a bit controversial is the use of > the same system call numbers across all architectures, synchronizing > all of them with the x86-32 numbers. With the new syscall.tbl > files, I hope we can just keep doing that in the future, and no > longer require the architecture maintainers to assign a number. > > This is mainly useful for implementers of the C libraries: if > we can add future system calls everywhere at the same time, using > a particular version of the kernel headers also guarantees that > the system call number macro is visible. > diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl > index 022fc099b628..428cf512a757 100644 > --- a/arch/s390/kernel/syscalls/syscall.tbl > +++ b/arch/s390/kernel/syscalls/syscall.tbl > @@ -391,3 +391,15 @@ > 381 common kexec_file_load sys_kexec_file_load compat_sys_kexec_file_load > 382 common io_pgetevents sys_io_pgetevents compat_sys_io_pgetevents > 383 common rseq sys_rseq compat_sys_rseq > +# room for arch specific syscalls > +392 64 semtimedop sys_semtimedop - > +393 common semget sys_semget sys_semget ... > +395 common shmget sys_shmget sys_shmget ... > +398 common shmdt sys_shmdt sys_shmdt > +399 common msgget sys_msgget sys_msgget These four need compat system call wrappers, unfortunately... (well, actually only shmget and shmdt require them, but let's add them for all four). See arch/s390/kernel/compat_wrapper.c I'm afraid this compat special handling will be even more annoying in the future, since s390 will be the only architecture which requires this special handling. _Maybe_ it would make sense to automatically generate a weak compat system call wrapper for s390 with the SYSCALL_DEFINE macros, but that probably won't work in all cases.