Re: [PATCH v4 21/28] rust: alloc: remove `GlobalAlloc` and `krealloc_aligned`

[Danilo Krummrich <dakr@kernel.org>]

On Wed, Aug 07, 2024 at 09:23:04PM +0000, Benno Lossin wrote:
> On 05.08.24 17:19, Danilo Krummrich wrote:
> > Now that we have all the `Allocator`s and the kernel `Box` and `Vec`
> > implementations in place, remove `GlobalAlloc` and `krealloc_aligned`.
> 
> When I try to compile this patch, then I get this error:
> 
>       UPD     include/generated/utsversion.h
>       CC      init/version-timestamp.o
>       KSYMS   .tmp_vmlinux0.kallsyms.S
>       AS      .tmp_vmlinux0.kallsyms.o
>       LD      .tmp_vmlinux1
>     ld.lld: error: undefined symbol: __rust_realloc
>     >>> referenced by usercopy_64.c
>     >>>               vmlinux.o:(alloc::raw_vec::finish_grow::<alloc::alloc::Global>)
>     
>     ld.lld: error: undefined symbol: __rust_alloc
>     >>> referenced by usercopy_64.c
>     >>>               vmlinux.o:(alloc::raw_vec::finish_grow::<alloc::alloc::Global>)
>     make[2]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
> 
> So maybe the `#[global_allocator]` needs to stay until we remove the
> `alloc` dependency?

Yes, I think so. I compile checked the single patches with `M=rust` and
`M=drivers`, which only compiles, but doesn't link things, so it didn't catch
it.

> 
> ---
> Cheers,
> Benno
> 
> > Signed-off-by: Danilo Krummrich <dakr@kernel.org>
> > ---
> >  rust/kernel/alloc/allocator.rs | 63 ++--------------------------------
> >  1 file changed, 2 insertions(+), 61 deletions(-)
>