Re: [PATCH -next] memregion: Add arch_flush_memregion() interface

From: Borislav Petkov
Date: Wed Sep 07 2022 - 12:07:08 EST


On Mon, Aug 29, 2022 at 02:29:18PM -0700, Davidlohr Bueso wrote:
> diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
> index 1abd5438f126..18463cb704fb 100644
> --- a/arch/x86/mm/pat/set_memory.c
> +++ b/arch/x86/mm/pat/set_memory.c
> @@ -330,6 +330,20 @@ void arch_invalidate_pmem(void *addr, size_t size)
> EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
> #endif
>
> +#ifdef CONFIG_ARCH_HAS_MEMREGION_INVALIDATE
> +bool arch_has_flush_memregion(void)
> +{
> + return !cpu_feature_enabled(X86_FEATURE_HYPERVISOR);

This looks really weird. Why does this need to care about HV at all?

Does that nfit stuff even run in guests?

> +EXPORT_SYMBOL(arch_has_flush_memregion);

...

> +EXPORT_SYMBOL(arch_flush_memregion);

Why aren't those exports _GPL?

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette