Re: [PATCH v3 bpf RESEND 3/4] module: introduce module_alloc_huge

From: Song Liu
Date: Thu Apr 14 2022 - 17:03:40 EST


Hi Luis,

On Thu, Apr 14, 2022 at 1:34 PM Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote:
>
> On Thu, Apr 14, 2022 at 12:59:13PM -0700, Song Liu wrote:
> > Introduce module_alloc_huge, which allocates huge page backed memory in
> > module memory space. The primary user of this memory is bpf_prog_pack
> > (multiple BPF programs sharing a huge page).
> >
> > Signed-off-by: Song Liu <song@xxxxxxxxxx>
>
> See modules-next [0], as modules.c has been chopped up as of late.
> So if you want this to go throug modules this will need to rebased
> on that tree. fortunately the amount of code in question does not
> seem like much.
>
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/log/?h=modules-next

We are hoping to ship this with to 5.18, as the set addresses some issue with
huge page backed vmalloc. I guess we cannot ship it via modules-next branch.

How about we ship module_alloc_huge() to 5.18 in module.c for now, and once
we update modules-next branch, I will send another patch to clean it up?

Thanks,
Song