Re: [PATCH 13/15] modpost: Add support for hashing long symbol names

[Sami Tolvanen]

On Wed, Jun 19, 2024 at 01:47:13AM +0900, Masahiro Yamada wrote:
> On Tue, Jun 18, 2024 at 2:58 AM Sami Tolvanen <samitolvanen@xxxxxxxxxx> wrote:
> >
> > +#define barrier_data(ptr) __asm__ __volatile__("": :"r"(ptr) :"memory")
> 
> 
> 
> 
> I know this is a copy-paste of the kernel space code,
> but is barrier_data() also necessary for host programs?

I tested this with Clang and it worked fine without the barrier, but
with gcc, the code no longer produces correct values. Presumably this is
a load bearing data barrier.

Sami