Re: [PATCH v2 07/10] KVM: PPC: reimplement LOAD_FP/STORE_FP instruction mmio emulation with analyse_intr() input

2018-05-16 Thread Simon Guo 
On Thu, May 17, 2018 at 09:52:07AM +1000, Paul Mackerras wrote:
> On Mon, May 07, 2018 at 02:20:13PM +0800, wei.guo.si...@gmail.com wrote:
> > From: Simon Guo 
> > 
> > This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
> > analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
> > analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
> > accordingly.
> > 
> > For FP store MMIO emulation, the FP regs need to be flushed firstly so
> > that the right FP reg vals can be read from vcpu->arch.fpr, which will
> > be stored into MMIO data.
> > 
> > Suggested-by: Paul Mackerras 
> > Signed-off-by: Simon Guo 
> 
> One comment below, otherwise looks good...
> 
> >  arch/powerpc/kvm/emulate_loadstore.c | 197 
> > +++
> >  1 file changed, 40 insertions(+), 157 deletions(-)
> > 
> > diff --git a/arch/powerpc/kvm/emulate_loadstore.c 
> > b/arch/powerpc/kvm/emulate_loadstore.c
> > index 2a91845..5a6571c 100644
> > --- a/arch/powerpc/kvm/emulate_loadstore.c
> > +++ b/arch/powerpc/kvm/emulate_loadstore.c
> > @@ -138,6 +138,22 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
> >  
> > break;
> > }
> > +#ifdef CONFIG_PPC_FPU
> > +   case LOAD_FP:
> > +   if (kvmppc_check_fp_disabled(vcpu))
> > +   return EMULATE_DONE;
> > +
> > +   if (op.type & FPCONV)
> > +   vcpu->arch.mmio_sp64_extend = 1;
> > +
> > +   emulated = kvmppc_handle_load(run, vcpu,
> > +   KVM_MMIO_REG_FPR|op.reg, size, 1);
> 
> You need to check the SIGNEXT flag and call kvmppc_handle_loads if it
> is set, because of the lfiwax case:
> 
> > -   case OP_31_XOP_LFIWAX:
> > -   if (kvmppc_check_fp_disabled(vcpu))
> > -   return EMULATE_DONE;
> > -   emulated = kvmppc_handle_loads(run, vcpu,
> > -   KVM_MMIO_REG_FPR|rt, 4, 1);
> > -   break;

Yes. I need to handle that. Thanks for point it out.

BR,
 - Simon

Re: [PATCH v2 07/10] KVM: PPC: reimplement LOAD_FP/STORE_FP instruction mmio emulation with analyse_intr() input

2018-05-16 Thread Paul Mackerras 
On Mon, May 07, 2018 at 02:20:13PM +0800, wei.guo.si...@gmail.com wrote:
> From: Simon Guo 
> 
> This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
> analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
> analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
> accordingly.
> 
> For FP store MMIO emulation, the FP regs need to be flushed firstly so
> that the right FP reg vals can be read from vcpu->arch.fpr, which will
> be stored into MMIO data.
> 
> Suggested-by: Paul Mackerras 
> Signed-off-by: Simon Guo 

One comment below, otherwise looks good...

>  arch/powerpc/kvm/emulate_loadstore.c | 197 
> +++
>  1 file changed, 40 insertions(+), 157 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/emulate_loadstore.c 
> b/arch/powerpc/kvm/emulate_loadstore.c
> index 2a91845..5a6571c 100644
> --- a/arch/powerpc/kvm/emulate_loadstore.c
> +++ b/arch/powerpc/kvm/emulate_loadstore.c
> @@ -138,6 +138,22 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
>  
>   break;
>   }
> +#ifdef CONFIG_PPC_FPU
> + case LOAD_FP:
> + if (kvmppc_check_fp_disabled(vcpu))
> + return EMULATE_DONE;
> +
> + if (op.type & FPCONV)
> + vcpu->arch.mmio_sp64_extend = 1;
> +
> + emulated = kvmppc_handle_load(run, vcpu,
> + KVM_MMIO_REG_FPR|op.reg, size, 1);

You need to check the SIGNEXT flag and call kvmppc_handle_loads if it
is set, because of the lfiwax case:

> - case OP_31_XOP_LFIWAX:
> - if (kvmppc_check_fp_disabled(vcpu))
> - return EMULATE_DONE;
> - emulated = kvmppc_handle_loads(run, vcpu,
> - KVM_MMIO_REG_FPR|rt, 4, 1);
> - break;

Paul.

[PATCH v2 07/10] KVM: PPC: reimplement LOAD_FP/STORE_FP instruction mmio emulation with analyse_intr() input

2018-05-07 Thread wei . guo . simon 
From: Simon Guo 

This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
accordingly.

For FP store MMIO emulation, the FP regs need to be flushed firstly so
that the right FP reg vals can be read from vcpu->arch.fpr, which will
be stored into MMIO data.

Suggested-by: Paul Mackerras 
Signed-off-by: Simon Guo 
---
 arch/powerpc/kvm/emulate_loadstore.c | 197 +++
 1 file changed, 40 insertions(+), 157 deletions(-)

diff --git a/arch/powerpc/kvm/emulate_loadstore.c 
b/arch/powerpc/kvm/emulate_loadstore.c
index 2a91845..5a6571c 100644
--- a/arch/powerpc/kvm/emulate_loadstore.c
+++ b/arch/powerpc/kvm/emulate_loadstore.c
@@ -138,6 +138,22 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 
break;
}
+#ifdef CONFIG_PPC_FPU
+   case LOAD_FP:
+   if (kvmppc_check_fp_disabled(vcpu))
+   return EMULATE_DONE;
+
+   if (op.type & FPCONV)
+   vcpu->arch.mmio_sp64_extend = 1;
+
+   emulated = kvmppc_handle_load(run, vcpu,
+   KVM_MMIO_REG_FPR|op.reg, size, 1);
+
+   if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
+   kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
+
+   break;
+#endif
case STORE:
/* if need byte reverse, op.val has been reversed by
 * analyse_instr().
@@ -149,6 +165,30 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
 
break;
+#ifdef CONFIG_PPC_FPU
+   case STORE_FP:
+   if (kvmppc_check_fp_disabled(vcpu))
+   return EMULATE_DONE;
+
+   /* The FP registers need to be flushed so that
+* kvmppc_handle_store() can read actual FP vals
+* from vcpu->arch.
+*/
+   if (vcpu->kvm->arch.kvm_ops->giveup_ext)
+   vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
+   MSR_FP);
+
+   if (op.type & FPCONV)
+   vcpu->arch.mmio_sp64_extend = 1;
+
+   emulated = kvmppc_handle_store(run, vcpu,
+   VCPU_FPR(vcpu, op.reg), size, 1);
+
+   if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
+   kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
+
+   break;
+#endif
case CACHEOP:
/* Do nothing. The guest is performing dcbi because
 * hardware DMA is not snooped by the dcache, but
@@ -170,93 +210,6 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
switch (get_op(inst)) {
case 31:
switch (get_xop(inst)) {
-#ifdef CONFIG_PPC_FPU
-   case OP_31_XOP_LFSX:
-   if (kvmppc_check_fp_disabled(vcpu))
-   return EMULATE_DONE;
-   vcpu->arch.mmio_sp64_extend = 1;
-   emulated = kvmppc_handle_load(run, vcpu,
-   KVM_MMIO_REG_FPR|rt, 4, 1);
-   break;
-
-   case OP_31_XOP_LFSUX:
-   if (kvmppc_check_fp_disabled(vcpu))
-   return EMULATE_DONE;
-   vcpu->arch.mmio_sp64_extend = 1;
-   emulated = kvmppc_handle_load(run, vcpu,
-   KVM_MMIO_REG_FPR|rt, 4, 1);
-   kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-   break;
-
-   case OP_31_XOP_LFDX:
-   if (kvmppc_check_fp_disabled(vcpu))
-   return EMULATE_DONE;
-   emulated = kvmppc_handle_load(run, vcpu,
-   KVM_MMIO_REG_FPR|rt, 8, 1);
-   break;
-
-   case OP_31_XOP_LFDUX:
-   if (kvmppc_check_fp_disabled(vcpu))
-   return EMULATE_DONE;
-   emulated = kvmppc_handle_load(run, vcpu,
-   KVM_MMIO_REG_FPR|rt, 8, 1);
-   kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-   break;
-
-   case OP_31_XOP_LFIWAX:
-   if (kvmppc_check_fp_disabled(vcpu))
-