ARM: relocation out of range (when loading a module)

[Nicolas Pitre]

On Fri, 11 Feb 2011, Dave Martin wrote:

> On Fri, Feb 11, 2011 at 9:38 AM, Russell King - ARM Linux
> <linux at arm.linux.org.uk> wrote:
> > On Fri, Feb 11, 2011 at 09:31:04AM +0000, Dave Martin wrote:
> >> You could probably cook up a good upper bound based on the size of the
> >> kernel and the number of symbols in the module: i.e., assume that
> >> every undefined symbol in the module needs to be fixed up to point at
> >> the most distant symbol in the kernel.
> >>
> >> For people with normal-sized kernels, this bound will probably work
> >> out as zero most of the time (i.e., the current situation).  For
> >> people with big kernels, or when many modules are already loaded, it
> >> may work out at 100% -- but that's the price to pay for guaranteed
> >> preallocation of the space required for the veneers.  And anyway, you
> >> may really need a substantial chunk of those veneers in such cases.
> >
> > I think it's going to be easier just to re-order the kernel image link
> > order to solve that problem.  That just leaves uclinux...
> >
> 
> But if the kernel is big, or there are many modules, changing the
> order can't solve the problem surely?  Or is the problem purely caused
> by having the initramfs in the way, and we think the amount of actual
> code will never be big enough to cause a problem?

Right now the biggest problem comes from the size of the initramfs.  The 
solution for that is simply to move it elsewhere towards the end of the 
kernel image instead of at the beginning.  And I think we're good for a 
couple years before the actual kernel code size becomes an issue.


Nicolas