As found by gcc-4.8, the QUEUE_SYSFS_BIT_FNS macro creates functions that use a value generated by queue_var_store independent of whether that value was set or not.
block/blk-sysfs.c: In function 'queue_store_nonrot': block/blk-sysfs.c:244:385: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized] Unlike most other such warnings, this one is not a false positive, writing any non-number string into the sysfs files indeed has an undefined result, rather than returning an error. Signed-off-by: Arnd Bergmann <a...@arndb.de> Cc: Jens Axboe <jax...@fusionio.com> --- diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 6206a93..5efc5a6 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -229,6 +229,8 @@ queue_store_##name(struct request_queue *q, const char *page, size_t count) \ unsigned long val; \ ssize_t ret; \ ret = queue_var_store(&val, page, count); \ + if (ret < 0) \ + return ret; \ if (neg) \ val = !val; \ \ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/