On Mon, Aug 14, 2017 at 04:40:55PM +0100, Ard Biesheuvel wrote:

On 14 August 2017 at 16:32, Dave Martin [off-list ref] wrote:

quoted

On Mon, Aug 14, 2017 at 01:53:43PM +0100, Ard Biesheuvel wrote:

[...]

quoted

quoted

So use the above to implement the macros mov_l, adr_l, adrm_l (using ldm

I don't see adrm_l in this patch.

Oops (2)

Nico already mentioned that, and I failed to fix the commit log. I
added it at some point, but it wasn't really useful

Thought it might be something like that.

quoted

quoted

to load multiple literals at once), ldr_l and str_l, all of which will
use movw/movt pairs on v7 and later CPUs, and use PC-relative literals
otherwise.

Also...

By default, I'd assume that we should port _all_ uses of :upper16:/
:lower16: to use these.  Does this series consciously do that?  Are
there any exceptions?

There aren't that many. Anything that refers to absolute symbols will
break under CONFIG_RELOCATABLE and I haven't noticed any issues (I
tested extensively with Thumb2)

I don't mind open coded movw/movt for relative references in code that
is tightly coupled to a platform that guarantees v7+ so I didn't do a
full sweep. Also, I started with 50+ patches and tried to remove the
ones that are mostly orthogonal to the KASLR stuff.

OK, that sounds reasonable.

Cheers
---Dave