Re: [RFC PATCH 1/3] asm-generic: io: Add exec versions of ioremap

[Russell King - ARM Linux]

On Wed, May 18, 2016 at 10:25:03PM +0200, Arnd Bergmann wrote:
> The ARM version of ioremap_exec() that gets added in this patch is cached
> (like memremap()), but then the asm-generic version is not? This is
> even more confusing, it should at least do roughly the same thing across
> architectures.
> 
> There should also be some documentation about what the expected behavior is, e.g.:
> 
> - is memremap_exec() by default cached or not? (I assume it would
>   be like memremap())
> - If we have an interface that does explicit uncached executable mapping,
>   what about architectures on which this is not possible? Should they
>   fall back to cached or non-executable, or cause a link error?  

Another important point is whether atomic instructions / kernel locks
can be located within the mapped memory.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.