Re: [Question] import third-party crates in kernel modules

[Hanqing Zhao <ouckarlzhao@gmail.com>]

Hi Miguel,

I am actually writing a new alloc crate for linux kernel.

I aim to implement it as a cross-platform crate, which can be
used both in kernel and userland.

In general,
I currently have
- a faster lazy_static crate: static_init (https://crates.io/crates/static_init)
- crates for writing cfg easier: cfg_if (https://crates.io/crates/cfg_if)
- rand for random number generation (https://crates.io/crates/rand)
- syn for my heuristic marcos

Because my crate supports userspace as well,
it has some userland dependencies like
libc, winapi, criterion, and bencher (for benchmarking),
even if they won't be compiled for supporting kernel
allocation.

Of course, I can somehow remove those dependencies by replicating
them in my crate though.

Furthermore, I currently have dynamically generated codes in build.rs,
according to cpu numbers, cpu features, etc.

I think it would be better if we can import 3rd-party crates while
developing and testing our own kernel modules,
i.e., we do not need to guarantee that the kernel module having
3rd-party dependencies can become an in-tree module,
but we can compile a .ko that has a 3rd-part dependency
during offline development and testing.

Best,
Hanqing Zhao
Georgia Tech

On Mon, Apr 26, 2021 at 2:32 PM Miguel Ojeda
<miguel.ojeda.sandonis@gmail.com> wrote:
>
> Hi Hanqing,
>
> On Mon, Apr 26, 2021 at 7:01 PM Hanqing Zhao <ouckarlzhao@gmail.com> wrote:
> >
> > Is it possible to import third-party crates in the kernel modules?
> > (e.g., crates on crates.io)
> >
> > Any suggestions to import crates while writing kernel modules?  TIA.
>
> Which crates do you need? We may end up importing some things into the
> kernel (such as `alloc` and `syn`), but we do not plan to depend on
> crates.io (offline or otherwise).
>
> Cheers,
> Miguel