Re: [PATCH] ARM: module: fix MODULE_PLTS not work for KASAN

[Linus Walleij]

On Thu, Dec 23, 2021 at 12:01 PM Ard Biesheuvel <ardb@xxxxxxxxxx> wrote:
> On Thu, 23 Dec 2021 at 11:16, Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx> wrote:
> >
> > When we run out of module space address with ko insertion,
> > and with MODULE_PLTS, module would turn to try to find memory
> > from VMALLOC address space.
> >
> > Unfortunately, with KASAN enabled, VMALLOC doesn't work without
> > VMALLOC_KASAN which is unimplemented in ARM.
(...)
> This is not the right place to fix this. If module PLTs are
> incompatible with KAsan, they should not be selectable in Kconfig at
> the same time.
>
> But ideally, we should implement KASAN_VMALLOC for ARM as well - we
> also need this for the vmap'ed stacks.

I also need it for my kernel-in-vmalloc patch, I guess it's the
reason why I can't seem to get it to work. So a lot depends on
this.

Yours,
Linus Walleij