| Message ID | 1524657284-16706-9-git-send-email-wei.guo.simon@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 25, 2018 at 07:54:41PM +0800, wei.guo.simon@gmail.com wrote: > From: Simon Guo <wei.guo.simon@gmail.com> > > Currently HV will save math regs(FP/VEC/VSX) when trap into host. But > PR KVM will only save math regs when qemu task switch out of CPU. > > To emulate FP/VEC/VSX load, PR KVM need to flush math regs firstly and > then be able to update saved VCPU FPR/VEC/VSX area reasonably. > > This patch adds the giveup_ext() to KVM ops (an empty one for HV KVM) > and kvmppc_complete_mmio_load() can invoke that hook to flush math > regs accordingly. > > Math regs flush is also necessary for STORE, which will be covered > in later patch within this patch series. > > Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> I don't see where you have provided a function for Book E. I would suggest you only set the function pointer to non-NULL when the function is actually needed, i.e. for PR KVM. It seems to me that this means that emulation of FP/VMX/VSX loads is currently broken for PR KVM for the case where kvm_io_bus_read() is able to supply the data, and the emulation of FP/VMX/VSX stores is broken for PR KVM for all cases. Do you agree? > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > index 5b875ba..7eb5507 100644 > --- a/arch/powerpc/kvm/book3s_hv.c > +++ b/arch/powerpc/kvm/book3s_hv.c > @@ -2084,6 +2084,10 @@ static int kvmhv_set_smt_mode(struct kvm *kvm, unsigned long smt_mode, > return err; > } > > +static void kvmhv_giveup_ext(struct kvm_vcpu *vcpu, ulong msr) > +{ > +} > + > static void unpin_vpa(struct kvm *kvm, struct kvmppc_vpa *vpa) > { > if (vpa->pinned_addr) > @@ -4398,6 +4402,7 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) > .configure_mmu = kvmhv_configure_mmu, > .get_rmmu_info = kvmhv_get_rmmu_info, > .set_smt_mode = kvmhv_set_smt_mode, > + .giveup_ext = kvmhv_giveup_ext, > }; > > static int kvm_init_subcore_bitmap(void) I think HV KVM could leave this pointer as NULL, and then... > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > index 17f0315..e724601 100644 > --- a/arch/powerpc/kvm/powerpc.c > +++ b/arch/powerpc/kvm/powerpc.c > @@ -1061,6 +1061,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, > kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr); > break; > case KVM_MMIO_REG_FPR: > + if (!is_kvmppc_hv_enabled(vcpu->kvm)) > + vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_FP); > + This could become if (vcpu->kvm->arch.kvm_ops->giveup_ext) vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_FP); and you wouldn't need to fix Book E explicitly. Paul.
On Thu, May 03, 2018 at 04:08:17PM +1000, Paul Mackerras wrote: > On Wed, Apr 25, 2018 at 07:54:41PM +0800, wei.guo.simon@gmail.com wrote: > > From: Simon Guo <wei.guo.simon@gmail.com> > > > > Currently HV will save math regs(FP/VEC/VSX) when trap into host. But > > PR KVM will only save math regs when qemu task switch out of CPU. > > > > To emulate FP/VEC/VSX load, PR KVM need to flush math regs firstly and > > then be able to update saved VCPU FPR/VEC/VSX area reasonably. > > > > This patch adds the giveup_ext() to KVM ops (an empty one for HV KVM) > > and kvmppc_complete_mmio_load() can invoke that hook to flush math > > regs accordingly. > > > > Math regs flush is also necessary for STORE, which will be covered > > in later patch within this patch series. > > > > Signed-off-by: Simon Guo <wei.guo.simon@gmail.com> > > I don't see where you have provided a function for Book E. > > I would suggest you only set the function pointer to non-NULL when the > function is actually needed, i.e. for PR KVM. Got it. > > It seems to me that this means that emulation of FP/VMX/VSX loads is > currently broken for PR KVM for the case where kvm_io_bus_read() is > able to supply the data, and the emulation of FP/VMX/VSX stores is > broken for PR KVM for all cases. Do you agree? > Yes. I think so. > > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > > index 5b875ba..7eb5507 100644 > > --- a/arch/powerpc/kvm/book3s_hv.c > > +++ b/arch/powerpc/kvm/book3s_hv.c > > @@ -2084,6 +2084,10 @@ static int kvmhv_set_smt_mode(struct kvm *kvm, unsigned long smt_mode, > > return err; > > } > > > > +static void kvmhv_giveup_ext(struct kvm_vcpu *vcpu, ulong msr) > > +{ > > +} > > + > > static void unpin_vpa(struct kvm *kvm, struct kvmppc_vpa *vpa) > > { > > if (vpa->pinned_addr) > > @@ -4398,6 +4402,7 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) > > .configure_mmu = kvmhv_configure_mmu, > > .get_rmmu_info = kvmhv_get_rmmu_info, > > .set_smt_mode = kvmhv_set_smt_mode, > > + .giveup_ext = kvmhv_giveup_ext, > > }; > > > > static int kvm_init_subcore_bitmap(void) > > I think HV KVM could leave this pointer as NULL, and then... ok. > > > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > > index 17f0315..e724601 100644 > > --- a/arch/powerpc/kvm/powerpc.c > > +++ b/arch/powerpc/kvm/powerpc.c > > @@ -1061,6 +1061,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, > > kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr); > > break; > > case KVM_MMIO_REG_FPR: > > + if (!is_kvmppc_hv_enabled(vcpu->kvm)) > > + vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_FP); > > + > > This could become > if (vcpu->kvm->arch.kvm_ops->giveup_ext) > vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_FP); > > and you wouldn't need to fix Book E explicitly. Yes > > Paul. Thanks, - Simon
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index abe7032..b265538 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -324,6 +324,7 @@ struct kvmppc_ops { int (*get_rmmu_info)(struct kvm *kvm, struct kvm_ppc_rmmu_info *info); int (*set_smt_mode)(struct kvm *kvm, unsigned long mode, unsigned long flags); + void (*giveup_ext)(struct kvm_vcpu *vcpu, ulong msr); }; extern struct kvmppc_ops *kvmppc_hv_ops; diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 5b875ba..7eb5507 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2084,6 +2084,10 @@ static int kvmhv_set_smt_mode(struct kvm *kvm, unsigned long smt_mode, return err; } +static void kvmhv_giveup_ext(struct kvm_vcpu *vcpu, ulong msr) +{ +} + static void unpin_vpa(struct kvm *kvm, struct kvmppc_vpa *vpa) { if (vpa->pinned_addr) @@ -4398,6 +4402,7 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) .configure_mmu = kvmhv_configure_mmu, .get_rmmu_info = kvmhv_get_rmmu_info, .set_smt_mode = kvmhv_set_smt_mode, + .giveup_ext = kvmhv_giveup_ext, }; static int kvm_init_subcore_bitmap(void) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 67061d3..be26636 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1782,6 +1782,7 @@ static long kvm_arch_vm_ioctl_pr(struct file *filp, #ifdef CONFIG_PPC_BOOK3S_64 .hcall_implemented = kvmppc_hcall_impl_pr, #endif + .giveup_ext = kvmppc_giveup_ext, }; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 17f0315..e724601 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -1061,6 +1061,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr); break; case KVM_MMIO_REG_FPR: + if (!is_kvmppc_hv_enabled(vcpu->kvm)) + vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_FP); + VCPU_FPR(vcpu, vcpu->arch.io_gpr & KVM_MMIO_REG_MASK) = gpr; break; #ifdef CONFIG_PPC_BOOK3S @@ -1074,6 +1077,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, #endif #ifdef CONFIG_VSX case KVM_MMIO_REG_VSX: + if (!is_kvmppc_hv_enabled(vcpu->kvm)) + vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_VSX); + if (vcpu->arch.mmio_vsx_copy_type == KVMPPC_VSX_COPY_DWORD) kvmppc_set_vsr_dword(vcpu, gpr); else if (vcpu->arch.mmio_vsx_copy_type == KVMPPC_VSX_COPY_WORD) @@ -1088,6 +1094,9 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, #endif #ifdef CONFIG_ALTIVEC case KVM_MMIO_REG_VMX: + if (!is_kvmppc_hv_enabled(vcpu->kvm)) + vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu, MSR_VEC); + kvmppc_set_vmx_dword(vcpu, gpr); break; #endif