Re: [Qemu-ppc] [Qemu-devel] [PATCH 1/6 v6] ppc: debug stub: Get trap instruction opcode from KVM

[Peter Maydell]

On 10 July 2014 11:57, Bharat Bhushan <address@hidden> wrote:
> Get trap instruction opcode from KVM and this opcode will
> be used for setting software breakpoint in following patch
>
> Signed-off-by: Bharat Bhushan <address@hidden>
> ---
> v5->v6
>  - no change
>
>  target-ppc/kvm.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
> index 2d87108..4df23dd 100644
> --- a/target-ppc/kvm.c
> +++ b/target-ppc/kvm.c
> @@ -72,6 +72,8 @@ static int cap_papr;
>  static int cap_htab_fd;
>  static int cap_fixup_hcalls;
>
> +static uint32_t debug_inst_opcode;
> +
>  /* XXX We have a race condition where we actually have a level triggered
>   *     interrupt, but the infrastructure can't expose that yet, so the guest
>   *     takes but ignores it, goes to sleep and never gets notified that 
> there's
> @@ -436,6 +438,8 @@ int kvm_arch_init_vcpu(CPUState *cs)
>          break;
>      }
>
> +    kvm_get_one_reg(cs, KVM_REG_PPC_DEBUG_INST, &debug_inst_opcode);
> +

Presumably the kernel guarantees that this is always the
same value for every CPU in the system?

thanks
-- PMM