[PATCH] ARM: two possible fixes for the KALLSYMS build problem

[Russell King - ARM Linux]

On Tue, Jun 12, 2012 at 09:02:29AM -0700, David Brown wrote:
> On Tue, Jun 12, 2012 at 03:32:49PM +0100, Russell King - ARM Linux wrote:
> > On Mon, Jun 11, 2012 at 01:37:48PM -0700, David Brown wrote:
> > > On Fri, Jun 01, 2012 at 09:21:59AM -0700, David Brown wrote:
> > > 
> > > > David Brown (1):
> > > >   ARM: Prevent KALLSYM size mismatch on ARM.
> > > > 
> > > >  arch/arm/kernel/vmlinux.lds.S |    3 +++
> > > >  1 file changed, 3 insertions(+)
> > > 
> > > Just wondering if anyone has had a chance to look at either of these,
> > > or try them.  I haven't seen any KALLSYMS mismatch build errors with
> > > either of these patches applied.
> > 
> > I think variant 2 is the better approach out of either as it doesn't add
> > to the size of the resulting kernel image.
> 
> The first variant doesn't ever increase the size of the kernel,
> either.  Variant two actually makes it a little smaller, since a few
> symbols are eliminated.

Ok.

> The second variant is cleaner, though as long as it is safe in every
> configuration.

Well, we don't have any per-CPU data unless we're building for SMP.
See:

#ifndef PER_CPU_BASE_SECTION
#ifdef CONFIG_SMP
#define PER_CPU_BASE_SECTION ".data..percpu"
#else
#define PER_CPU_BASE_SECTION ".data"
#endif
#endif

in include/asm-generic/percpu.h.