On 15/03/2018 11:08 PM, Bart Van Assche wrote:
> Avoid that building with W=1 triggers the following compiler warning:
>
> drivers/md/bcache/super.c:776:20: warning: comparison is always false due to limited range of data type [-Wtype-limits]
> d->nr_stripes > SIZE_MAX / sizeof(atomic_t)) {
> ^
>
> Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Reviewed-by: Coly Li <colyli@xxxxxxx>
Thanks.
Coly Li
> ---
> drivers/md/bcache/super.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index e8dfa804bd98..87c1f853bbb3 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -769,6 +769,8 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
> sector_t sectors)
> {
> struct request_queue *q;
> + const size_t max_stripes = min_t(size_t, INT_MAX,
> + SIZE_MAX / sizeof(atomic_t));
> size_t n;
> int idx;
>
> @@ -777,9 +779,7 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
>
> d->nr_stripes = DIV_ROUND_UP_ULL(sectors, d->stripe_size);
>
> - if (!d->nr_stripes ||
> - d->nr_stripes > INT_MAX ||
> - d->nr_stripes > SIZE_MAX / sizeof(atomic_t)) {
> + if (!d->nr_stripes || d->nr_stripes > max_stripes) {
> pr_err("nr_stripes too large or invalid: %u (start sector beyond end of disk?)",
> (unsigned)d->nr_stripes);
> return -ENOMEM;
>
