Re: [PATCH 5.7 0/6] 5.7.14-rc1 review

From: Daniel Díaz
Date: Wed Aug 05 2020 - 15:26:39 EST


Hello!

On Wed, 5 Aug 2020 at 13:37, Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Wed, Aug 5, 2020 at 11:24 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> >
> > Same with older versions of gcc. I don't see the problem with the
> > mainline kernel.
>
> https://www.youtube.com/watch?v=-b5aW08ivHU
>
> > I think this is caused by more recursive includes.
> > arch/arm64/include/asm/archrandom.h includes include/linux/random.h
> > which includes arch/arm64/include/asm/archrandom.h to get the definition
> > of arch_get_random_seed_long_early (which it won't get because of
> > the recursion).
> >
> > What I don't really understand is how this works with new versions
> > of gcc.
>
> Is that the only place it triggers?

Yes

> Because the trivial fix would be something like the appended, which is
> the right thing to do anyway.
>
> Linus
>
> diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c
> index 07c4c8cc4a67..9ded4237e1c1 100644
> --- a/arch/arm64/kernel/kaslr.c
> +++ b/arch/arm64/kernel/kaslr.c
> @@ -11,8 +11,8 @@
> #include <linux/sched.h>
> #include <linux/types.h>
> #include <linux/pgtable.h>
> +#include <linux/random.h>
>
> -#include <asm/archrandom.h>
> #include <asm/cacheflush.h>
> #include <asm/fixmap.h>
> #include <asm/kernel-pgtable.h>

Tested-by: Daniel Díaz <daniel.diaz@xxxxxxxxxx>

This patch works fine. Built with gcc 7.3.0 and glibc 2.27.

Greetings!

Daniel Díaz
daniel.diaz@xxxxxxxxxx