Re: [PATCH] [v5] Add gdb break point support to PowerPC kvm

[Jerone Young <jyoung5@us.ibm.com>]

On Mon, 2008-06-09 at 15:51 -0500, Hollis Blanchard wrote:
> On Mon, 2008-06-09 at 13:19 -0500, Jerone Young wrote:
> > 4 files changed, 128 insertions(+), 2 deletions(-)
> > arch/powerpc/kvm/booke_guest.c      |   16 +++++
> > arch/powerpc/kvm/booke_interrupts.S |    3 
> > arch/powerpc/kvm/powerpc.c          |  106 ++++++++++++++++++++++++++++++++++-
> > include/asm-powerpc/kvm_host.h      |    5 +
> > 
> > 
> >  * Boiled down conditional for dbsr to one line, when handling debug interrupts.
> >    Renamed load_guest_debug_registers() to guest_load_debug_registers()
> > 
> > This patch adds the ability to use breakpoints from a gdb stub in userpace (currently qemu). It does this through the use of hardware debug registers.
> > 
> > Signed-off-by: Jerone Young <jyoung5@us.ibm.com>
> 
> You still have not renamed restore_host_debug_state() and
> guest_load_debug_registers(), which you agreed to previously.

My bad.  I was mainly just addressing the issues we went over this
morning. I'll fix the names. 

> 
> You still have not renamed guest_debug(), which you also agreed to
> previously. I don't see why you have a separate function for this
> anyways.
> 
> You also have not addressed the case I pointed out where an IAC matches
> after you've programmed it but before you've entered the guest.

Basically can disable them in the dbcr0 before we do any switching out
of registers.

If an IAC is matched before we enter the guest it will be caught host
that catches it.