[PATCH] ARM: force linker to use PIC veneers

[Dave.Martin@arm.com (Dave P Martin)]

On Thu, Mar 26, 2015 at 12:24:01PM +0000, Ard Biesheuvel wrote:
> On 26 March 2015 at 13:22, Russell King - ARM Linux
> <linux@arm.linux.org.uk> wrote:
> > On Thu, Mar 26, 2015 at 01:20:16PM +0100, Ard Biesheuvel wrote:

[...]

> >> Any specific concerns? The --pic-veneer switch dates back to 2009, so
> >> it's been around for a while
> >
> > BX.  Not every CPU supports BX.
> >
> 
> The bx is used for the Thumb -> ARM switch inside the veneer only, so
> if you build for ARM these won't appear in the output

Agreed that's what's _supposed_ to happen.

Note that --use-blx is an override and might introduce BXs into a kernel
that otherwise doesn't have them.  But in any case, this option doesn't
show a benefit for the scenario under discussion, hence my dropping the
request (conditional on THUMB2_KERNEL in any case).

Ard, can you should build a couple of !THUMB2_KERNEL/pre-v5
configurations with your change and check, just to be sure?

Cheers
---Dave