In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be compared against __BYTE_ORDER in preprocessor conditionals where these are exposed to userspace (that is they're not inside __KERNEL__ conditionals).
However, in the main kernel the norm is to check for "defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and this has incorrectly leaked into the userspace headers. The definition of struct mdp_superblock_s in linux/raid/md_p.h is wrong in this way. Note that userspace will likely interpret the ordering of the fields incorrectly as the big-endian variant on a little-endian machines - depending on header inclusion order. [!!!] NOTE [!!!] This patch may adversely change the userspace API. It might be better to fix the ordering of events_hi, events_lo, cp_events_hi and cp_events_lo in struct mdp_superblock_s / typedef mdp_super_t. Signed-off-by: David Howells <[email protected]> cc: Neil Brown <[email protected]> cc: [email protected] --- include/uapi/linux/raid/md_p.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/raid/md_p.h b/include/uapi/linux/raid/md_p.h index ee75353..fe1a540 100644 --- a/include/uapi/linux/raid/md_p.h +++ b/include/uapi/linux/raid/md_p.h @@ -145,16 +145,18 @@ typedef struct mdp_superblock_s { __u32 failed_disks; /* 4 Number of failed disks */ __u32 spare_disks; /* 5 Number of spare disks */ __u32 sb_csum; /* 6 checksum of the whole superblock */ -#ifdef __BIG_ENDIAN +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN) __u32 events_hi; /* 7 high-order of superblock update count */ __u32 events_lo; /* 8 low-order of superblock update count */ __u32 cp_events_hi; /* 9 high-order of checkpoint update count */ __u32 cp_events_lo; /* 10 low-order of checkpoint update count */ -#else +#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) __u32 events_lo; /* 7 low-order of superblock update count */ __u32 events_hi; /* 8 high-order of superblock update count */ __u32 cp_events_lo; /* 9 low-order of checkpoint update count */ __u32 cp_events_hi; /* 10 high-order of checkpoint update count */ +#else +#error unspecified endianness #endif __u32 recovery_cp; /* 11 recovery checkpoint sector count */ /* There are only valid for minor_version > 90 */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
