Subject: Re: [PATCH v3] powerpc/kvm: support to handle sw breakpoint

From: Alexander Graf <[email-masked]>
Date: Mon, 11 Aug 2014 11:15:38 +0200

On 11.08.14 10:51, Benjamin Herrenschmidt wrote:
> On Mon, 2014-08-11 at 09:26 +0200, Alexander Graf wrote:
>>> diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
>>> index da86d9b..d95014e 100644
>>> --- a/arch/powerpc/kvm/emulate.c
>>> +++ b/arch/powerpc/kvm/emulate.c
>> This should be book3s_emulate.c.
> Any reason we can't make that 00dddd00 opcode as breakpoint common to
> all powerpc variants ?

I can't think of a good reason. We use a hypercall on booke (which traps 
into an illegal instruction for pr) today, but I don't think it has to 
be that way.

Given that the user space API allows us to change it dynamically, there 
should be nothing blocking us from going with 00dddd00 always.

Alex