Re: [PATCH 3/7] KVM: PPC: debug stub interface parameter defined

[Alexander Graf <agraf@suse.de>]

On 28.02.2013, at 05:13, Bharat Bhushan wrote:

> This patch defines the interface parameter for KVM_SET_GUEST_DEBUG
> ioctl support. Follow up patches will use this for setting up
> hardware breakpoints, watchpoints and software breakpoints.
> 
> Also kvm_arch_vcpu_ioctl_set_guest_debug() is brought one level below.
> This is because I am not sure what is required for book3s. So this ioctl
> behaviour will not change for book3s.
> 
> Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
> ---
> arch/powerpc/include/uapi/asm/kvm.h |   23 +++++++++++++++++++++++
> arch/powerpc/kvm/book3s.c           |    6 ++++++
> arch/powerpc/kvm/booke.c            |    6 ++++++
> arch/powerpc/kvm/powerpc.c          |    6 ------
> 4 files changed, 35 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
> index c2ff99c..15f9a00 100644
> --- a/arch/powerpc/include/uapi/asm/kvm.h
> +++ b/arch/powerpc/include/uapi/asm/kvm.h
> @@ -272,8 +272,31 @@ struct kvm_debug_exit_arch {
> 
> /* for KVM_SET_GUEST_DEBUG */
> struct kvm_guest_debug_arch {
> +	struct {
> +		/* H/W breakpoint/watchpoint address */
> +		__u64 addr;
> +		/*
> +		 * Type denotes h/w breakpoint, read watchpoint, write
> +		 * watchpoint or watchpoint (both read and write).
> +		 */
> +#define KVMPPC_DEBUG_NOTYPE		0x0
> +#define KVMPPC_DEBUG_BREAKPOINT		(1UL << 1)
> +#define KVMPPC_DEBUG_WATCH_WRITE	(1UL << 2)
> +#define KVMPPC_DEBUG_WATCH_READ		(1UL << 3)
> +		__u32 type;
> +		__u32 reserved;
> +	} bp[16];
> };
> 
> +/* Debug related defines */
> +/*
> + * kvm_guest_debug->control is a 32 bit field. The lower 16 bits are generic
> + * and upper 16 bits are architecture specific. Architecture specific defines
> + * that ioctl is for setting hardware breakpoint or software breakpoint.
> + */
> +#define KVM_GUESTDBG_USE_SW_BP		0x00010000
> +#define KVM_GUESTDBG_USE_HW_BP		0x00020000

You only need

#define KVM_GUESTDBG_HW_BP 0x00010000

In absence of the flag, it's a SW breakpoint.


Alex

> +
> /* definition of registers in kvm_run */
> struct kvm_sync_regs {
> };
> diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
> index 975a401..cb85d73 100644
> --- a/arch/powerpc/kvm/book3s.c
> +++ b/arch/powerpc/kvm/book3s.c
> @@ -613,6 +613,12 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
> 	return 0;
> }
> 
> +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
> +					struct kvm_guest_debug *dbg)
> +{
> +	return -EINVAL;
> +}
> +
> void kvmppc_decrementer_func(unsigned long data)
> {
> 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
> diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
> index a41cd6d..1de93a8 100644
> --- a/arch/powerpc/kvm/booke.c
> +++ b/arch/powerpc/kvm/booke.c
> @@ -1527,6 +1527,12 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg)
> 	return r;
> }
> 
> +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
> +					 struct kvm_guest_debug *dbg)
> +{
> +	return -EINVAL;
> +}
> +
> int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
> {
> 	return -ENOTSUPP;
> diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
> index 934413c..4c94ca9 100644
> --- a/arch/powerpc/kvm/powerpc.c
> +++ b/arch/powerpc/kvm/powerpc.c
> @@ -532,12 +532,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
> #endif
> }
> 
> -int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
> -                                        struct kvm_guest_debug *dbg)
> -{
> -	return -EINVAL;
> -}
> -
> static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
>                                      struct kvm_run *run)
> {
> -- 
> 1.7.0.4
> 
>