Re: [PATCH] rust: time: add debug assertions for out-of-range input in fsleep()

["Onur Özkan" <work@onurozkan.dev>]

On Sat, 09 May 2026 02:38:27 +0900
Sang-Heon Jeon <ekffu200098@gmail.com> wrote:

> fsleep() documents out-of-range input as a bug but does not check
> it, unlike udelay(). Add `debug_assert!` calls to catch it in
> debug builds.
> 
> Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
> ---
> Hello,
> 
> I found this small inconsistency while reading the code. The same
> check was applied to udelay() [1] but does not seem to have been
> extended to fsleep(). Please let me know if I have misunderstood
> anything.
> 
> [1] https://lore.kernel.org/all/20251103112958.2961517-2-fujita.tomonori@gmail.com
> 
> Best Regards,
> Sang-Heon Jeon
> ---
>  rust/kernel/time/delay.rs | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/rust/kernel/time/delay.rs b/rust/kernel/time/delay.rs
> index b5b1b42797a0..1e699fe647ff 100644
> --- a/rust/kernel/time/delay.rs
> +++ b/rust/kernel/time/delay.rs
> @@ -32,6 +32,9 @@ pub fn fsleep(delta: Delta) {
>      // overflow inside fsleep, which could lead to unintentional infinite sleep.
>      const MAX_DELTA: Delta = Delta::from_micros(i32::MAX as i64);
>  
> +    debug_assert!(delta.as_nanos() >= 0);
> +    debug_assert!(delta <= MAX_DELTA);
> +
>      let delta = if (Delta::ZERO..=MAX_DELTA).contains(&delta) {
>          delta
>      } else {
> -- 
> 2.43.0
> 

Reviewed-by: Onur Özkan <work@onurozkan.dev>