Re: Package for development of out-of-tree kernel modules written in Rust

From	Ben Hutchings <ben@decadent.org.uk>
Newsgroups	linux.debian.kernel
Subject	Re: Package for development of out-of-tree kernel modules written in Rust
Date	2025-04-16 17:40 +0200
Message-ID	<KCd1L-dYbt-5@gated-at.bofh.it> (permalink)
References	(10 earlier) <Kxwy5-aOvY-1@gated-at.bofh.it> <KxxXb-aPhh-3@gated-at.bofh.it> <KxAil-aRi4-3@gated-at.bofh.it> <KxAs2-aRlS-5@gated-at.bofh.it> <KyFSF-bDwQ-7@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

[Multipart message — attachments visible in raw view] - view raw

On Sun, 2025-04-06 at 23:21 +0200, Miguel Ojeda wrote:
> On Thu, Apr 3, 2025 at 11:32 PM NoisyCoil <noisycoil@disroot.org> wrote:
> > 
> > I think the key issue here is Debian wants to support cross-compiling
> > out-of-tree kernel modules,
> 
> I see, that sentence explains it, thanks!
> 
> So you want to build a kernel for architecture X in a host of
> architecture Y, and then build an out-of-tree module for architecture
> X in a host of architecture Z (possibly X)?
> 
> As far as I have been told, the kernel generally requires that the
> exact same toolchain is used to build out-of-tree modules as the main
> kernel -- so the same host/target pair should be used for both the
> kernel build as the out-of-tree builds. Of course, things may happen
> to work otherwise.

I don't see why there would be a problem with mixing objects built using
native and cross- C compilers with the same target and version.  (Unless
you enable gcc plugins, which we don't.)

> Is the reason that there is a build farm on architecture Y that builds
> all the kernels for all X, and then you want users to be able to use
> their architecture X to build out-of-tree modules for their kernel on
> X? i.e. the X == Z case.

Official Debian binary packages are built natively, but there is also a
standard way to cross-build them and the kernel source package supports
this.  The resulting binary packages should be functionally identical.

We also try to give users the option to cross-build or natively build
out-of-tree modules, independently of that.  We apply a patch to always
define CROSS_COMPILE according to the target architecture.  (This works
even for the native case because e.g. x86_64-linux-gnu-gcc exists as a
native compiler on amd64.)

Ben.

-- 
Ben Hutchings
The obvious mathematical breakthrough [to break modern encryption]
would be development of an easy way to factor large prime numbers.
                                                           - Bill Gates

Thread

Package for development of out-of-tree kernel modules written in Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 01:30 +0100
  Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-02-26 12:50 +0100
    Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 13:20 +0100
      Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-26 14:00 +0100
        Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 15:20 +0100
          Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-26 19:30 +0100
            Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 22:00 +0100
              Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-27 18:40 +0100
        Re: Package for development of out-of-tree kernel modules written  in Rust Ben Hutchings <ben@decadent.org.uk> - 2025-02-26 19:20 +0100
          Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 19:30 +0100
            Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-26 20:10 +0100
              Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 20:20 +0100
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-27 18:40 +0100
              Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-02 23:00 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-02 23:30 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-02 23:40 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-03 00:50 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-03 16:50 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-03 19:30 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-03 21:00 +0200
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-04-03 23:30 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-03 23:40 +0200
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-04-06 23:40 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-12 18:50 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-13 13:40 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-13 17:40 +0200
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-04-13 18:40 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-04-13 20:30 +0200
                Re: Package for development of out-of-tree kernel modules written  in Rust Ben Hutchings <ben@decadent.org.uk> - 2025-04-16 17:40 +0200
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-05-03 17:10 +0200
                Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-04-04 11:20 +0200
                Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-04-06 23:40 +0200
          Re: Package for development of out-of-tree kernel modules written in Rust Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> - 2025-02-26 19:40 +0100
      Re: Package for development of out-of-tree kernel modules written in  Rust NoisyCoil <noisycoil@disroot.org> - 2025-02-26 14:40 +0100
      Re: Package for development of out-of-tree kernel modules written in  Rust Bastian Blank <waldi@debian.org> - 2025-02-26 14:40 +0100

csiph-web