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* [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
@ 2025-10-13  0:14 Miguel Ojeda
  2025-10-13  9:20 ` Alice Ryhl
  0 siblings, 1 reply; 6+ messages in thread
From: Miguel Ojeda @ 2025-10-13  0:14 UTC (permalink / raw)
  To: Miguel Ojeda, Alex Gaynor, Alice Ryhl, Burak Emir
  Cc: Boqun Feng, Gary Guo, Björn Roy Baron, Benno Lossin,
	Andreas Hindborg, Trevor Gross, Danilo Krummrich, rust-for-linux,
	Yury Norov, linux-kernel, patches

Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
take the address of a union field [1][2]:

      CLIPPY L rust/kernel.o
    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:169:13
        |
    169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block
        |
        = note: `-D unused-unsafe` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(unused_unsafe)]`

    error: unnecessary `unsafe` block
       --> rust/kernel/bitmap.rs:185:13
        |
    185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
        |             ^^^^^^ unnecessary `unsafe` block

Thus allow both instances to clean the warning in newer compilers.

Link: https://github.com/rust-lang/rust/issues/141264 [1]
Link: https://github.com/rust-lang/rust/pull/141469 [2]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/bitmap.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/rust/kernel/bitmap.rs b/rust/kernel/bitmap.rs
index f45915694454..711b8368b38f 100644
--- a/rust/kernel/bitmap.rs
+++ b/rust/kernel/bitmap.rs
@@ -166,6 +166,7 @@ impl core::ops::Deref for BitmapVec {
     fn deref(&self) -> &Bitmap {
         let ptr = if self.nbits <= BITS_PER_LONG {
             // SAFETY: Bitmap is represented inline.
+            #[allow(unused_unsafe, reason = "Safe since Rust 1.92.0")]
             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
         } else {
             // SAFETY: Bitmap is represented as array of `unsigned long`.
@@ -182,6 +183,7 @@ impl core::ops::DerefMut for BitmapVec {
     fn deref_mut(&mut self) -> &mut Bitmap {
         let ptr = if self.nbits <= BITS_PER_LONG {
             // SAFETY: Bitmap is represented inline.
+            #[allow(unused_unsafe, reason = "Safe since Rust 1.92.0")]
             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
         } else {
             // SAFETY: Bitmap is represented as array of `unsigned long`.

base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
-- 
2.51.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
  2025-10-13  0:14 [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning Miguel Ojeda
@ 2025-10-13  9:20 ` Alice Ryhl
  2025-10-14 16:09   ` Yury Norov
  0 siblings, 1 reply; 6+ messages in thread
From: Alice Ryhl @ 2025-10-13  9:20 UTC (permalink / raw)
  To: Miguel Ojeda
  Cc: Alex Gaynor, Burak Emir, Boqun Feng, Gary Guo,
	Björn Roy Baron, Benno Lossin, Andreas Hindborg,
	Trevor Gross, Danilo Krummrich, rust-for-linux, Yury Norov,
	linux-kernel, patches

On Mon, Oct 13, 2025 at 02:14:22AM +0200, Miguel Ojeda wrote:
> Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
> take the address of a union field [1][2]:
> 
>       CLIPPY L rust/kernel.o
>     error: unnecessary `unsafe` block
>        --> rust/kernel/bitmap.rs:169:13
>         |
>     169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
>         |             ^^^^^^ unnecessary `unsafe` block
>         |
>         = note: `-D unused-unsafe` implied by `-D warnings`
>         = help: to override `-D warnings` add `#[allow(unused_unsafe)]`
> 
>     error: unnecessary `unsafe` block
>        --> rust/kernel/bitmap.rs:185:13
>         |
>     185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
>         |             ^^^^^^ unnecessary `unsafe` block
> 
> Thus allow both instances to clean the warning in newer compilers.
> 
> Link: https://github.com/rust-lang/rust/issues/141264 [1]
> Link: https://github.com/rust-lang/rust/pull/141469 [2]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Alice Ryhl <aliceryhl@google.com>


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
  2025-10-13  9:20 ` Alice Ryhl
@ 2025-10-14 16:09   ` Yury Norov
  2025-10-14 16:21     ` Alice Ryhl
  0 siblings, 1 reply; 6+ messages in thread
From: Yury Norov @ 2025-10-14 16:09 UTC (permalink / raw)
  To: Alice Ryhl
  Cc: Miguel Ojeda, Alex Gaynor, Burak Emir, Boqun Feng, Gary Guo,
	Björn Roy Baron, Benno Lossin, Andreas Hindborg,
	Trevor Gross, Danilo Krummrich, rust-for-linux, linux-kernel,
	patches

On Mon, Oct 13, 2025 at 09:20:15AM +0000, Alice Ryhl wrote:
> On Mon, Oct 13, 2025 at 02:14:22AM +0200, Miguel Ojeda wrote:
> > Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
> > take the address of a union field [1][2]:
> > 
> >       CLIPPY L rust/kernel.o
> >     error: unnecessary `unsafe` block
> >        --> rust/kernel/bitmap.rs:169:13
> >         |
> >     169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
> >         |             ^^^^^^ unnecessary `unsafe` block
> >         |
> >         = note: `-D unused-unsafe` implied by `-D warnings`
> >         = help: to override `-D warnings` add `#[allow(unused_unsafe)]`
> > 
> >     error: unnecessary `unsafe` block
> >        --> rust/kernel/bitmap.rs:185:13
> >         |
> >     185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
> >         |             ^^^^^^ unnecessary `unsafe` block
> > 
> > Thus allow both instances to clean the warning in newer compilers.
> > 
> > Link: https://github.com/rust-lang/rust/issues/141264 [1]
> > Link: https://github.com/rust-lang/rust/pull/141469 [2]
> > Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> 
> Reviewed-by: Alice Ryhl <aliceryhl@google.com>

Added in bitmap-for-next.

Thanks,
Yury

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
  2025-10-14 16:09   ` Yury Norov
@ 2025-10-14 16:21     ` Alice Ryhl
  2025-10-14 16:23       ` Yury Norov
  0 siblings, 1 reply; 6+ messages in thread
From: Alice Ryhl @ 2025-10-14 16:21 UTC (permalink / raw)
  To: Yury Norov
  Cc: Miguel Ojeda, Alex Gaynor, Burak Emir, Boqun Feng, Gary Guo,
	Björn Roy Baron, Benno Lossin, Andreas Hindborg,
	Trevor Gross, Danilo Krummrich, rust-for-linux, linux-kernel,
	patches

On Tue, Oct 14, 2025 at 12:09:09PM -0400, Yury Norov wrote:
> On Mon, Oct 13, 2025 at 09:20:15AM +0000, Alice Ryhl wrote:
> > On Mon, Oct 13, 2025 at 02:14:22AM +0200, Miguel Ojeda wrote:
> > > Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
> > > take the address of a union field [1][2]:
> > > 
> > >       CLIPPY L rust/kernel.o
> > >     error: unnecessary `unsafe` block
> > >        --> rust/kernel/bitmap.rs:169:13
> > >         |
> > >     169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
> > >         |             ^^^^^^ unnecessary `unsafe` block
> > >         |
> > >         = note: `-D unused-unsafe` implied by `-D warnings`
> > >         = help: to override `-D warnings` add `#[allow(unused_unsafe)]`
> > > 
> > >     error: unnecessary `unsafe` block
> > >        --> rust/kernel/bitmap.rs:185:13
> > >         |
> > >     185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
> > >         |             ^^^^^^ unnecessary `unsafe` block
> > > 
> > > Thus allow both instances to clean the warning in newer compilers.
> > > 
> > > Link: https://github.com/rust-lang/rust/issues/141264 [1]
> > > Link: https://github.com/rust-lang/rust/pull/141469 [2]
> > > Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> > 
> > Reviewed-by: Alice Ryhl <aliceryhl@google.com>
> 
> Added in bitmap-for-next.

Is there any possibility of landing this for an -rc of 6.18 instead of
for 6.19-rc1? That way, the warning won't be present when compiling 6.18
with rustc 1.92.0 and newer.

Alice

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
  2025-10-14 16:21     ` Alice Ryhl
@ 2025-10-14 16:23       ` Yury Norov
  2025-10-14 16:42         ` Miguel Ojeda
  0 siblings, 1 reply; 6+ messages in thread
From: Yury Norov @ 2025-10-14 16:23 UTC (permalink / raw)
  To: Alice Ryhl
  Cc: Miguel Ojeda, Alex Gaynor, Burak Emir, Boqun Feng, Gary Guo,
	Björn Roy Baron, Benno Lossin, Andreas Hindborg,
	Trevor Gross, Danilo Krummrich, rust-for-linux, linux-kernel,
	patches

On Tue, Oct 14, 2025 at 04:21:51PM +0000, Alice Ryhl wrote:
> On Tue, Oct 14, 2025 at 12:09:09PM -0400, Yury Norov wrote:
> > On Mon, Oct 13, 2025 at 09:20:15AM +0000, Alice Ryhl wrote:
> > > On Mon, Oct 13, 2025 at 02:14:22AM +0200, Miguel Ojeda wrote:
> > > > Starting with Rust 1.92.0 (expected 2025-12-11), Rust allows to safely
> > > > take the address of a union field [1][2]:
> > > > 
> > > >       CLIPPY L rust/kernel.o
> > > >     error: unnecessary `unsafe` block
> > > >        --> rust/kernel/bitmap.rs:169:13
> > > >         |
> > > >     169 |             unsafe { core::ptr::addr_of!(self.repr.bitmap) }
> > > >         |             ^^^^^^ unnecessary `unsafe` block
> > > >         |
> > > >         = note: `-D unused-unsafe` implied by `-D warnings`
> > > >         = help: to override `-D warnings` add `#[allow(unused_unsafe)]`
> > > > 
> > > >     error: unnecessary `unsafe` block
> > > >        --> rust/kernel/bitmap.rs:185:13
> > > >         |
> > > >     185 |             unsafe { core::ptr::addr_of_mut!(self.repr.bitmap) }
> > > >         |             ^^^^^^ unnecessary `unsafe` block
> > > > 
> > > > Thus allow both instances to clean the warning in newer compilers.
> > > > 
> > > > Link: https://github.com/rust-lang/rust/issues/141264 [1]
> > > > Link: https://github.com/rust-lang/rust/pull/141469 [2]
> > > > Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> > > 
> > > Reviewed-by: Alice Ryhl <aliceryhl@google.com>
> > 
> > Added in bitmap-for-next.
> 
> Is there any possibility of landing this for an -rc of 6.18 instead of
> for 6.19-rc1? That way, the warning won't be present when compiling 6.18
> with rustc 1.92.0 and newer.

OK, will do -rc1

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning
  2025-10-14 16:23       ` Yury Norov
@ 2025-10-14 16:42         ` Miguel Ojeda
  0 siblings, 0 replies; 6+ messages in thread
From: Miguel Ojeda @ 2025-10-14 16:42 UTC (permalink / raw)
  To: Yury Norov
  Cc: Alice Ryhl, Miguel Ojeda, Alex Gaynor, Burak Emir, Boqun Feng,
	Gary Guo, Björn Roy Baron, Benno Lossin, Andreas Hindborg,
	Trevor Gross, Danilo Krummrich, rust-for-linux, linux-kernel,
	patches

On Tue, Oct 14, 2025 at 6:23 PM Yury Norov <yury.norov@gmail.com> wrote:
>
> OK, will do -rc1

Thanks Yury!

Yeah, these should generally be sent as "fixes" to Linus; otherwise we
will have red CIs.

(I don't add the Fixes tag for this sort of change because the
original code is fine).

Cheers,
Miguel

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2025-10-14 16:42 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2025-10-13  0:14 [PATCH] rust: bitmap: clean Rust 1.92.0 `unused_unsafe` warning Miguel Ojeda
2025-10-13  9:20 ` Alice Ryhl
2025-10-14 16:09   ` Yury Norov
2025-10-14 16:21     ` Alice Ryhl
2025-10-14 16:23       ` Yury Norov
2025-10-14 16:42         ` Miguel Ojeda

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