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[Dave P Martin]

On Tue, Apr 21, 2015 at 11:18:08AM +0100, Ard Biesheuvel wrote:
> On 21 April 2015 at 12:13, Russell King - ARM Linux
> <linux at arm.linux.org.uk> wrote:
> > On Tue, Apr 21, 2015 at 12:08:51PM +0200, Ard Biesheuvel wrote:
> >> This updates the PROCINFO offset-to-setup-function fields of the
> >> Thumb2 capable CPU definitions to include the Thumb bit when building
> >> a Thumb2 kernel. This ensures that these function are always called
> >> in the correct mode.
> >
> > I don't think this is necessary, in fact, I think this is positively
> > regression causing.
> >
> > The symbol 'initfunc' is known to the assembler to be a thumb symbol.
> > As we have seen already from the kernel dumps from the V7M kernel, when
> > it calculates initfunc - name in a T2 kernel, the resulting value is an
> > _odd_ number.
> >
> 
> OK, so BSYM() uses '+ 1' rather than ' | 1'? I wasn't expecting that, sorry.

'| 1' is more logical, but can't be resolved at link time because
there's no relocation for this operation.  Hence '+ 1'.  This matters
for local cross-section references that can't be resolved at assembly
time.

> But looking at proc-v7.S again, the problem may just be the missing
> ENDPROC() declarations for a couple of the setup() functions, which
> explains why they are lacking the Thumb annotations.

Yes, if any are missing ENDPROC() then it should be added there.

Cheers
---Dave