Hi Vineet, On 11/03/13 12:29, Vineet Gupta wrote: > 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 ? FYI, for metag we assumed this was intentional and that IPC_64 shouldn't be passed since it is the default behaviour for new arches. You may find the following uClibc commit relevant: http://git.uclibc.org/uClibc/commit/?id=6c2fa3451f35f8d78a31689044b2d19efa4eaca2 Cheers James -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
