Re: 2.4.9-ac12 ppc ftr_fixup

On Sun, 26 Aug 2001 20:04:04 -0700,
Tom Rini [off-list ref] wrote:

On Mon, Aug 27, 2001 at 12:47:57PM +1000, Keith Owens wrote:

quoted

do_cpu_ftr_fixups() replaces unsupported code with NOP, based on the
table from __start___ftr_fixup to __stop___ftr_fixup which contains all
the data marked as section(__ftr_fixup).  Fine, but it only handles
section __ftr_fixup data in the kernel, it does not write NOP over
__ftr_fixup data in modules.  So any code marked as section __ftr_fixup
in a module executes unchanged.  Unless I am missing something, that is
a problem.

After a bit more digging, I'm pretty sure it's not much of a problem.
get_cycles seems to be either a) SMP or b) DRM or c) arcnet related.
a and b aren't an issue for 601 (no SMP and possible but unlikely that
DRM will work on a machine w/ a 601).  If there's an arcnet PCI card, I suppose
it could be an issue then...  Anyhow...

It is more than just get_cycles().  Look at the places that ftr is used,
  fgrep -r BEGIN_FTR_SECTION include/asm-ppc* arch/ppc*
If any of that code ends up in a module then the problem exists.


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