Add the equivalent of the `___ADDRESSABLE()` annotation in the
`module_{init,exit}` macros to the Rust `module!` macro.
Without this, `objtool` would complain if enabled for Rust, e.g.:
samples/rust/rust_print.o: warning: objtool: cleanup_module(): not an indirect call target
samples/rust/rust_print.o: warning: objtool: init_module(): not an indirect call target
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
rust/macros/module.rs | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 411dc103d82e..571ffa2e189c 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -256,6 +256,12 @@ mod __module_init {{
unsafe {{ __init() }}
}}
+ #[cfg(MODULE)]
+ #[doc(hidden)]
+ #[used]
+ #[link_section = \".init.data\"]
+ static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module;
+
#[cfg(MODULE)]
#[doc(hidden)]
#[no_mangle]
@@ -269,6 +275,12 @@ mod __module_init {{
unsafe {{ __exit() }}
}}
+ #[cfg(MODULE)]
+ #[doc(hidden)]
+ #[used]
+ #[link_section = \".exit.data\"]
+ static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module;
+
// Built-in modules are initialized through an initcall pointer
// and the identifiers need to be unique.
#[cfg(not(MODULE))]
--
2.45.2On Wed, 24 Jul 2024 18:14:54 +0200
Miguel Ojeda <ojeda@kernel.org> wrote:
> Add the equivalent of the `___ADDRESSABLE()` annotation in the
> `module_{init,exit}` macros to the Rust `module!` macro.
>
> Without this, `objtool` would complain if enabled for Rust, e.g.:
>
> samples/rust/rust_print.o: warning: objtool: cleanup_module(): not an indirect call target
> samples/rust/rust_print.o: warning: objtool: init_module(): not an indirect call target
>
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> ---
> rust/macros/module.rs | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/rust/macros/module.rs b/rust/macros/module.rs
> index 411dc103d82e..571ffa2e189c 100644
> --- a/rust/macros/module.rs
> +++ b/rust/macros/module.rs
> @@ -256,6 +256,12 @@ mod __module_init {{
> unsafe {{ __init() }}
> }}
>
> + #[cfg(MODULE)]
> + #[doc(hidden)]
> + #[used]
> + #[link_section = \".init.data\"]
Should this be in section `.discard.addressable` instead?
> + static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module;
> +
> #[cfg(MODULE)]
> #[doc(hidden)]
> #[no_mangle]
> @@ -269,6 +275,12 @@ mod __module_init {{
> unsafe {{ __exit() }}
> }}
>
> + #[cfg(MODULE)]
> + #[doc(hidden)]
> + #[used]
> + #[link_section = \".exit.data\"]
> + static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module;
> +
> // Built-in modules are initialized through an initcall pointer
> // and the identifiers need to be unique.
> #[cfg(not(MODULE))]
On Wed, 24 Jul 2024 20:46:49 +0100 Gary Guo <gary@garyguo.net> wrote:
>
> Should this be in section `.discard.addressable` instead?
No, we need to mimic the call to `___ADDRESSABLE()` (i.e. the one with
3 underscores, not 2), which passes `__{init,exit}data`.
By the way, thanks for the reviews Gary!
Cheers,
Miguel
On Thu, 25 Jul 2024 19:47:13 +0200
Miguel Ojeda <ojeda@kernel.org> wrote:
> On Wed, 24 Jul 2024 20:46:49 +0100 Gary Guo <gary@garyguo.net> wrote:
> >
> > Should this be in section `.discard.addressable` instead?
>
> No, we need to mimic the call to `___ADDRESSABLE()` (i.e. the one with
> 3 underscores, not 2), which passes `__{init,exit}data`.
>
> By the way, thanks for the reviews Gary!
>
> Cheers,
> Miguel
You're right. It's a bit difficult to navigate macros :)
In this case I think this indeed matches the C implementation.
Reviewed-by: Gary Guo <gary@garyguo.net>
Thanks,
Gary
On Wed, 24 Jul 2024 20:46:49 +0100 Gary Guo <gary@garyguo.net> wrote:
>
> On Wed, 24 Jul 2024 18:14:54 +0200
> Miguel Ojeda <ojeda@kernel.org> wrote:
>
> > Add the equivalent of the `___ADDRESSABLE()` annotation in the
> > `module_{init,exit}` macros to the Rust `module!` macro.
> >
> > Without this, `objtool` would complain if enabled for Rust, e.g.:
> >
> > samples/rust/rust_print.o: warning: objtool: cleanup_module(): not an indirect call target
> > samples/rust/rust_print.o: warning: objtool: init_module(): not an indirect call target
> >
> > Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> > ---
> > rust/macros/module.rs | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> >
> > diff --git a/rust/macros/module.rs b/rust/macros/module.rs
> > index 411dc103d82e..571ffa2e189c 100644
> > --- a/rust/macros/module.rs
> > +++ b/rust/macros/module.rs
> > @@ -256,6 +256,12 @@ mod __module_init {{
> > unsafe {{ __init() }}
> > }}
> >
> > + #[cfg(MODULE)]
> > + #[doc(hidden)]
> > + #[used]
> > + #[link_section = \".init.data\"]
>
> Should this be in section `.discard.addressable` instead?
>
> > + static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module;
> > +
> > #[cfg(MODULE)]
> > #[doc(hidden)]
> > #[no_mangle]
> > @@ -269,6 +275,12 @@ mod __module_init {{
> > unsafe {{ __exit() }}
> > }}
> >
> > + #[cfg(MODULE)]
> > + #[doc(hidden)]
> > + #[used]
> > + #[link_section = \".exit.data\"]
> > + static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module;
> > +
> > // Built-in modules are initialized through an initcall pointer
> > // and the identifiers need to be unique.
> > #[cfg(not(MODULE))]
Boot-tested under QEMU for Rust:
Tested-by: Miguel Ojeda <ojeda@kernel.org>
Thanks!
Cheers,
Miguel
On Thu, Jul 25, 2024 at 7:45 PM Miguel Ojeda <ojeda@kernel.org> wrote: > > Boot-tested under QEMU for Rust: Sorry, please ignore this message. I run a script of mine badly... :) Cheers, Miguel
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