Re: [PATCH V2 08/11] arch/kmap: Ensure kmap_prot visibility

From: Ira Weiny
Date: Wed May 06 2020 - 16:33:50 EST


On Tue, May 05, 2020 at 11:13:26PM -0700, Christoph Hellwig wrote:
> On Sun, May 03, 2020 at 06:09:09PM -0700, ira.weiny@xxxxxxxxx wrote:
> > From: Ira Weiny <ira.weiny@xxxxxxxxx>
> >
> > We want to support kmap_atomic_prot() on all architectures and it makes
> > sense to define kmap_atomic() to use the default kmap_prot.
> >
> > So we ensure all arch's have a globally available kmap_prot either as a
> > define or exported symbol.
>
> FYI, I still think a
>
> #ifndef kmap_prot
> #define kmap_prot PAGE_KERNEL
> #endif
>
> in linux/highmem.h would be nicer. Then only xtensa and sparc need
> to override it and clearly stand out.

That would be nice... But... in this particular patch kmap_prot needs to be
in arch/microblaze/include/asm/highmem.h to preserve bisect-ability.

So there would be an inversion with this define and the core #ifndef...

I like the change but I'm going to add this change as a follow on patch because
at the end of the series microblaze no longer needs this.

If this is reasonable could I get a review on this patch to add to the next
series?

Ira