cpu_vm_mask checks in ARM flush functions

[Russell King - ARM Linux]

On Mon, Oct 26, 2009 at 10:22:26AM +0000, Catalin Marinas wrote:
> On Sat, 2009-10-24 at 12:10 +0100, Russell King - ARM Linux wrote:
> > On Fri, Oct 23, 2009 at 09:03:16PM -0700, muni anda wrote:
> > > I was going though the cache flush functions in arch/arm/mm/flush.c
> > > and found that cpu_isset() is used at a lot of places. I couldn't
> > > understand the reason why there is a need for cpu_vm_mask checks? My
> > > understanding was that those functions will be executed on the CPU for
> > > which the cpu_mask is already set (in switch_mm call). Is there a
> > > different calling sequence that I am missing?
> [...]
> > For VIPT non-aliasing caches, there may be a bug there; it requires
> > more time than I currently have to think about to say for certain
> > though.
> 
> Someone in ARM mentioned that setting breakpoints on ARM11MPCore doesn't
> always work. I gave them a patch with cpu_vm_mask check removed but they
> said it still doesn't work. I cannot guarantee that the fix doesn't work
> until I try it but I haven't had time for it yet.

Since I don't have an EABI gdb, I can't test it either.

Was the ARM11MPCore system being tested one which broadcasts the cache ops
in hardware?