Re: [PATCH v15 0/5] rust: adds Bitmap API, ID pool and bindings

[Yury ooNorov <yury.norov@gmail.com>]

+ Philip Li <philip.li@intel.com>

On Fri, Sep 05, 2025 at 11:29:22AM +0200, Miguel Ojeda wrote:
> On Thu, Sep 4, 2025 at 8:02 PM Yury Norov <yury.norov@gmail.com> wrote:
> >
> > Added in bitmap-for-next for testing. Thanks!
> 
> linux-next breaks with CONFIG_RUST_BITMAP_HARDENED=y:
> 
>      error[E0425]: cannot find function `owned_bitmap_out_of_bounds`
> in this scope
>        --> rust/kernel/bitmap.rs:484:1
>         |
>     484 | #[kunit_tests(rust_kernel_bitmap)]
>         | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
> 
> because the proc macro doesn't support `cfg`s (moving it below
> `#[test]` wouldn't work either). I have filled:
> 
>     https://github.com/Rust-for-Linux/linux/issues/1185
> 
> so that we don't forget about it.
> 
> Meanwhile, I would recommend e.g. moving the `cfg` inside the
> function, something like:
> 
>     diff --git a/rust/kernel/bitmap.rs b/rust/kernel/bitmap.rs
>     index 6e0824579781..2f00e91e9c35 100644
>     --- a/rust/kernel/bitmap.rs
>     +++ b/rust/kernel/bitmap.rs
>     @@ -551,18 +551,21 @@ fn bitmap_set_clear_find() -> Result<(), AllocError> {
>              Ok(())
>          }
> 
>     -    #[cfg(not(CONFIG_RUST_BITMAP_HARDENED))]
>          #[test]
>          fn owned_bitmap_out_of_bounds() -> Result<(), AllocError> {
>     -        let mut b = BitmapVec::new(128, GFP_KERNEL)?;
>     +        #[cfg(not(CONFIG_RUST_BITMAP_HARDENED))]
>     +        {
>     +            let mut b = BitmapVec::new(128, GFP_KERNEL)?;
>     +
>     +            b.set_bit(2048);
>     +            b.set_bit_atomic(2048);
>     +            b.clear_bit(2048);
>     +            b.clear_bit_atomic(2048);
>     +            assert_eq!(None, b.next_bit(2048));
>     +            assert_eq!(None, b.next_zero_bit(2048));
>     +            assert_eq!(None, b.last_bit());
>     +        }
> 
>     -        b.set_bit(2048);
>     -        b.set_bit_atomic(2048);
>     -        b.clear_bit(2048);
>     -        b.clear_bit_atomic(2048);
>     -        assert_eq!(None, b.next_bit(2048));
>     -        assert_eq!(None, b.next_zero_bit(2048));
>     -        assert_eq!(None, b.last_bit());
>              Ok(())
>          }

Thanks for the testing, Miguel! I've folded-in your fix and added
your co-developed-by tag. Please let me know if it doesn't work for
you.

Philip, is it possible to add CONFIG_RUST_BITMAP_HARDENED=y/n in your
testing too?

Thanks,
Yury