Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754134Ab3CKM3u (ORCPT ); Mon, 11 Mar 2013 08:29:50 -0400 Received: from hermes.synopsys.com ([198.182.44.81]:63600 "EHLO hermes.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753905Ab3CKM3s (ORCPT ); Mon, 11 Mar 2013 08:29:48 -0400 Message-ID: <513DCE2D.6010800@synopsys.com> Date: Mon, 11 Mar 2013 17:59:33 +0530 From: Vineet Gupta User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: Arnd Bergmann CC: James Hogan , , Subject: SYSV IPC broken for no-legacy syscall kernels (was Re: [RFC PATCH v1 26/31] ARC: Build system: Makefiles, Kconfig, Linker script) References: <1352281674-2186-1-git-send-email-vgupta@synopsys.com> <1352281674-2186-27-git-send-email-vgupta@synopsys.com> <201211071413.49178.arnd@arndb.de> In-Reply-To: <201211071413.49178.arnd@arndb.de> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.12.197.217] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1905 Lines: 49 Hi Arnd, On Wednesday 07 November 2012 07:43 PM, Arnd Bergmann wrote: > On Wednesday 07 November 2012, Vineet Gupta wrote: > >> + >> +config ARC >> + def_bool y >> + select ARCH_WANT_IPC_PARSE_VERSION >> + # ARC Busybox based initramfs absolutely relies on DEVTMPFS for /dev >> + # DEVTMPS in turn needs HOTPLUG >> + select DEVTMPFS if !INITRAMFS_SOURCE="" >> + select GENERIC_ATOMIC64 >> + select GENERIC_CLOCKEVENTS >> + select GENERIC_FIND_FIRST_BIT >> + # for now, we don't need GENERIC_IRQ_PROBE, CONFIG_GENERIC_IRQ_CHIP >> + select GENERIC_IRQ_SHOW >> + select GENERIC_PENDING_IRQ if SMP >> + select GENERIC_SMP_IDLE_THREAD >> + select HAVE_GENERIC_HARDIRQS >> + select HOTPLUG if !INITRAMFS_SOURCE="" >> + select MODULES_USE_ELF_RELA > You should not need ARCH_WANT_IPC_PARSE_VERSION It seems, we have a small bug in sysV IPC. A lot of LTP tests have started failing on ARC 3.9-rc1 kernel due to absence of ARCH_WANT_IPC_PARSE_VERSION. I'm assuming that for newer arches, msgctl(2) and friends need to have need to have @cmd of type 0x01nn where 0x0100 is IPC_64. However for ! ARCH_WANT_IPC_PARSE_VERSION, ipc/util.h seems to be defining a dummy version of ipc_parse_version(), which doesn't strip out the 0x0100 from @cmds, causing the code to not enter the switch block in SYSCALL_DEFINE3(msgctl) making it fail. Adding the above item to arch/arc/Kconfig obviously fixes the breakage. It seems there is some bogosity in the way ipc_parse_version() is defined. Given the way it is used, to strip out the 0x0100 bit, it seems we always need the function variant - the IA-64 ish comment in there seems to be bit-rot. What do you think ? -Vineet -- 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/