Re: [PATCH] objtool/rust: relax slice condition to cover more `noreturn` Rust functions

[Joel Fernandes <joelagnelf@nvidia.com>]

On Tue, May 20, 2025 at 08:55:55PM +0200, Miguel Ojeda wrote:
> Developers are indeed hitting other of the `noreturn` slice symbols in
> Nova [1], thus relax the last check in the list so that we catch all of
> them, i.e.
> 
>     *_4core5slice5index22slice_index_order_fail
>     *_4core5slice5index24slice_end_index_len_fail
>     *_4core5slice5index26slice_start_index_len_fail
>     *_4core5slice5index29slice_end_index_overflow_fail
>     *_4core5slice5index31slice_start_index_overflow_fail
> 
> These all exist since at least Rust 1.78.0, thus backport it too.
> 
> See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
> for more details.
> 
> Cc: stable@vger.kernel.org # Needed in 6.12.y and later.
> Cc: John Hubbard <jhubbard@nvidia.com>
> Cc: Timur Tabi <ttabi@nvidia.com>
> Cc: Kane York <kanepyork@gmail.com>
> Cc: Josh Poimboeuf <jpoimboe@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Reported-by: Joel Fernandes <joelagnelf@nvidia.com>

Fixes our nova-core warnings.

Tested-by: Joel Fernandes <joelagnelf@nvidia.com>

thanks,

 - Joel


> Link: https://lore.kernel.org/rust-for-linux/20250513180757.GA1295002@joelnvbox/ [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> ---
> I tested it with the Timur's `alex` branch, but a Tested-by is appreciated.
> Thanks!
> 
>  tools/objtool/check.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index b21b12ec88d9..f23bdda737aa 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -230,7 +230,8 @@ static bool is_rust_noreturn(const struct symbol *func)
>  	       str_ends_with(func->name, "_7___rustc17rust_begin_unwind")				||
>  	       strstr(func->name, "_4core9panicking13assert_failed")					||
>  	       strstr(func->name, "_4core9panicking11panic_const24panic_const_")			||
> -	       (strstr(func->name, "_4core5slice5index24slice_") &&
> +	       (strstr(func->name, "_4core5slice5index") &&
> +		strstr(func->name, "slice_") &&
>  		str_ends_with(func->name, "_fail"));
>  }
> 
> 
> base-commit: a5806cd506af5a7c19bcd596e4708b5c464bfd21
> --
> 2.49.0