From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753625Ab2A0UiC (ORCPT ); Fri, 27 Jan 2012 15:38:02 -0500 Received: from terminus.zytor.com ([198.137.202.10]:51037 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751977Ab2A0UiA (ORCPT ); Fri, 27 Jan 2012 15:38:00 -0500 Message-ID: <4F230AF9.1010104@zytor.com> Date: Fri, 27 Jan 2012 12:37:13 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Glauber Costa CC: KOSAKI Motohiro , gorcunov@openvz.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, ebiederm@xmission.com, xemul@openvz.org, xemul@parallels.com, avagin@openvz.org, kosaki.motohiro@gmail.com, mingo@elte.hu, tglx@linutronix.de, andi@firstfloor.org, tj@kernel.org, matthltc@us.ibm.com, penberg@kernel.org, eric.dumazet@gmail.com, segoon@openwall.com, adobriyan@gmail.com, Valdis.Kletnieks@vt.edu Subject: Re: [RFC c/r 2/4] [RFC] syscalls, x86: Add __NR_kcmp syscall v7 References: <20120127175342.273260614@openvz.org> <20120127175939.795551339@openvz.org> <4F2306BB.5090907@jp.fujitsu.com> <4F230A40.8000203@parallels.com> In-Reply-To: <4F230A40.8000203@parallels.com> X-Enigmail-Version: 1.3.5 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/27/2012 12:34 PM, Glauber Costa wrote: >>> + case KCMP_SYSVSEM: >>> +#ifdef CONFIG_SYSVIPC >>> + ret = kcmp_ptr((long)task1->sysvsem.undo_list, >>> + (long)task2->sysvsem.undo_list, >>> + KCMP_SYSVSEM); >>> +#else >>> + ret = -EINVAL; >> >> ENOTSUP is better, I think. because of, EINVAL implicitly mean _caller_ is wrong. >> but in this case, it is not bad. only the kernel doesn't have enough feature. >> > > Isn't it usually the case for ENOSYS, then ? > ENOSYS means "no such system call". That would apply if the kcmp system call itself did not exist. -hpa