On Thu, Nov 2, 2017 at 9:17 PM, Babu Moger <babu.moger@xxxxxxxxxx> wrote: > > On 11/2/2017 3:11 AM, Arnd Bergmann wrote: >> >> On Thu, Nov 2, 2017 at 7:25 AM, Luc Van Oostenryck >> <luc.vanoostenryck@xxxxxxxxx> wrote: >>> >>> On Thu, Nov 2, 2017 at 7:04 AM, Heiko Carstens >>> <heiko.carstens@xxxxxxxxxx> wrote: >>>> >>>> On Tue, Oct 31, 2017 at 06:22:08PM +0100, Luc Van Oostenryck wrote: >>>> >>>>> -CHECKFLAGS += -D__s390__ -D__s390x__ >>>>> +CHECKFLAGS += -D__s390__ -D__s390x__ -mbig-endian >>>> >>>> Applied, thanks! >>>> >>>> However something similar is required for _all_ architectures, e.g. >>>> setting >>>> -mlittle-endian for the same reason on big endian build machines. >>>> >>>> Therefore I would have expected to add the -m flag in the top-level >>>> Makefile depending on CONFIG_CPU_BIG_ENDIAN or CONFIG_CPU_KITTLE_ENDIAN. >>>> However it seems that not all architectures set any of these config >>>> options >>>> at all. >>>> >>>> If I remember correctly Arnd Bergmann was looking into this a couple of >>>> months ago(?)... >>> >>> I'm not aware of Arnd's work for this but I checked all architectures and >>> sent >>> patches for those which needed it (for endianness and machine size). >> >> I think the patch series in question was from Babu Moger (added to Cc >> here), >> see https://lkml.org/lkml/2017/7/6/583 >> >> The patches got merged into v4.14-rc1, but had a different goal, so >> I don't think Babu was trying to solve the problem for sparse. Adding it > > > Yes. Correct. I was not trying to solve this sparse problem. > >> to the top-level CHECKFLAGS sounds appropriate, we just can't do >> it for the general CFLAGS. > > Interesting.. > Do you think we should add these definitions(-mbig-endian) all the fixed big > endian architectures? Here is the list: > arch/frv/include/uapi/asm/byteorder.h > arch/h8300/include/asm/byteorder.h > arch/h8300/include/uapi/asm/byteorder.h > arch/m68k/include/uapi/asm/byteorder.h > arch/openrisc/include/uapi/asm/byteorder.h > arch/parisc/include/uapi/asm/byteorder.h > arch/s390/include/uapi/asm/byteorder.h > arch/sparc/include/uapi/asm/byteorder.h I've sent CHECKFLAGS patches for m68k, openrisc, parisc, s390 & sparc (I don't remember why I concluded it wasn't needed for frv & h8300, probably because I didn't saw any dependencies with something like __BYTE_ORDER__ or __{BIG,LITTLE}_ENDIAN__). But yes, adding the right -m flag at top-level would be slightly simpler. However, it should be noted that this is not always enough (for example, ARM need __ARMEL__/__ARMEB__). -- Luc -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
