On Thu, 27 Apr 2023 14:25:41 -0700 Sagi Shahar <sagis@xxxxxxxxxx> wrote: > On Tue, Apr 18, 2023 at 11:34 PM Zhi Wang <zhi.wang.linux@xxxxxxxxx> wrote: > > > > On Tue, 18 Apr 2023 10:47:44 -0700 > > Sagi Shahar <sagis@xxxxxxxxxx> wrote: > > > > > On Mon, Apr 17, 2023 at 11:28 PM Zhi Wang <zhi.wang.linux@xxxxxxxxx> wrote: > > > > > > > > On Fri, 7 Apr 2023 20:19:19 +0000 > > > > Sagi Shahar <sagis@xxxxxxxxxx> wrote: > > > > > > > > Is there any reaon that TDX doesn't need .vm_copy_enc_context_from? Or it is > > > > going to be deprecated? The patch comments needs to be refined according to > > > > Sean's KVM x86 maintainer book. > > > > > > To clarify, there are 2 types of migrations. live migration (between > > > different hosts) and intra-host (between kvm instances in the same > > > host) migration. This patchset deals with intra-host migration and > > > doesn't add support for live migration. > > > > > > vm_copy_enc_context_from is currently used for setting up the > > > migration helper for SEV live migration and therefore it is currently > > > not needed in this patcheset. > > > > Out of curiosity, Is this the migration helper you mentioned here also > > a SEV VM? > > I'm not that familiar with SEV migration but from what I understand > the answer is "not exactly". > It's a guest process that runs as part of the SEV VM firmware. > > There's some public information about it here: > https://lpc.events/event/11/contributions/958/attachments/769/1448/Live%20migration%20of%20confidential%20guests_LPC2021.pdf Thanks so much for the information. I spent some time on reading and digging around it didn't talk about how the callback will be used. It would be nice to see the whole picture then I guess I will have more comments. > > > > > > > > > > > > This should mostly match the logic in sev_vm_move_enc_context_from. > > > > > > > > > > Signed-off-by: Sagi Shahar <sagis@xxxxxxxxxx> > > > > > --- > > > > > arch/x86/kvm/vmx/main.c | 10 +++++++ > > > > > arch/x86/kvm/vmx/tdx.c | 56 ++++++++++++++++++++++++++++++++++++++ > > > > > arch/x86/kvm/vmx/tdx.h | 2 ++ > > > > > arch/x86/kvm/vmx/x86_ops.h | 5 ++++ > > > > > 4 files changed, 73 insertions(+) > > > > > > > > > > diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c > > > > > index 5b64fe5404958..9d5d0ac465bf6 100644 > > > > > --- a/arch/x86/kvm/vmx/main.c > > > > > +++ b/arch/x86/kvm/vmx/main.c > > > > > @@ -979,6 +979,14 @@ static int vt_vcpu_mem_enc_ioctl(struct kvm_vcpu *vcpu, void __user *argp) > > > > > return tdx_vcpu_ioctl(vcpu, argp); > > > > > } > > > > > > > > > > +static int vt_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) > > > > > +{ > > > > > + if (!is_td(kvm)) > > > > > + return -ENOTTY; > > > > > + > > > > > + return tdx_vm_move_enc_context_from(kvm, source_fd); > > > > > +} > > > > > + > > > > > #define VMX_REQUIRED_APICV_INHIBITS \ > > > > > ( \ > > > > > BIT(APICV_INHIBIT_REASON_DISABLE)| \ > > > > > @@ -1141,6 +1149,8 @@ struct kvm_x86_ops vt_x86_ops __initdata = { > > > > > .dev_mem_enc_ioctl = tdx_dev_ioctl, > > > > > .mem_enc_ioctl = vt_mem_enc_ioctl, > > > > > .vcpu_mem_enc_ioctl = vt_vcpu_mem_enc_ioctl, > > > > > + > > > > > + .vm_move_enc_context_from = vt_move_enc_context_from, > > > > > }; > > > > > > > > > > struct kvm_x86_init_ops vt_init_ops __initdata = { > > > > > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c > > > > > index 8af7e4e81c860..0999a6d827c99 100644 > > > > > --- a/arch/x86/kvm/vmx/tdx.c > > > > > +++ b/arch/x86/kvm/vmx/tdx.c > > > > > @@ -2826,3 +2826,59 @@ int __init tdx_init(void) > > > > > INIT_LIST_HEAD(&per_cpu(associated_tdvcpus, cpu)); > > > > > return 0; > > > > > } > > > > > + > > > > > +static __always_inline bool tdx_guest(struct kvm *kvm) > > > > > +{ > > > > > + struct kvm_tdx *tdx_kvm = to_kvm_tdx(kvm); > > > > > + > > > > > + return tdx_kvm->finalized; > > > > > +} > > > > > + > > > > > +static int tdx_migrate_from(struct kvm *dst, struct kvm *src) > > > > > +{ > > > > > + return -EINVAL; > > > > > +} > > > > > + > > > > > +int tdx_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) > > > > > +{ > > > > > + struct kvm_tdx *dst_tdx = to_kvm_tdx(kvm); > > > > > + struct file *src_kvm_file; > > > > > + struct kvm_tdx *src_tdx; > > > > > + struct kvm *src_kvm; > > > > > + int ret; > > > > > + > > > > > + src_kvm_file = fget(source_fd); > > > > > + if (!file_is_kvm(src_kvm_file)) { > > > > > + ret = -EBADF; > > > > > + goto out_fput; > > > > > + } > > > > > + src_kvm = src_kvm_file->private_data; > > > > > + src_tdx = to_kvm_tdx(src_kvm); > > > > > + > > > > > + ret = pre_move_enc_context_from(kvm, src_kvm, > > > > > + &dst_tdx->migration_in_progress, > > > > > + &src_tdx->migration_in_progress); > > > > > + if (ret) > > > > > + goto out_fput; > > > > > + > > > > > + if (tdx_guest(kvm) || !tdx_guest(src_kvm)) { > > > > > + ret = -EINVAL; > > > > > + goto out_post; > > > > > + } > > > > > + > > > > > + ret = tdx_migrate_from(kvm, src_kvm); > > > > > + if (ret) > > > > > + goto out_post; > > > > > + > > > > > + kvm_vm_dead(src_kvm); > > > > > + ret = 0; > > > > > + > > > > > +out_post: > > > > > + post_move_enc_context_from(kvm, src_kvm, > > > > > + &dst_tdx->migration_in_progress, > > > > > + &src_tdx->migration_in_progress); > > > > > +out_fput: > > > > > + if (src_kvm_file) > > > > > + fput(src_kvm_file); > > > > > + return ret; > > > > > +} > > > > > diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h > > > > > index 71818c5001862..21b7e710be1fd 100644 > > > > > --- a/arch/x86/kvm/vmx/tdx.h > > > > > +++ b/arch/x86/kvm/vmx/tdx.h > > > > > @@ -24,6 +24,8 @@ struct kvm_tdx { > > > > > atomic_t tdh_mem_track; > > > > > > > > > > u64 tsc_offset; > > > > > + > > > > > + atomic_t migration_in_progress; > > > > > }; > > > > > > > > > > union tdx_exit_reason { > > > > > diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h > > > > > index d049e0c72ed0c..275f5d75e9bf1 100644 > > > > > --- a/arch/x86/kvm/vmx/x86_ops.h > > > > > +++ b/arch/x86/kvm/vmx/x86_ops.h > > > > > @@ -187,6 +187,8 @@ int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp); > > > > > void tdx_flush_tlb(struct kvm_vcpu *vcpu); > > > > > int tdx_sept_tlb_remote_flush(struct kvm *kvm); > > > > > void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level); > > > > > + > > > > > +int tdx_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd); > > > > > #else > > > > > static inline int tdx_init(void) { return 0; }; > > > > > static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return -ENOSYS; } > > > > > @@ -241,6 +243,9 @@ static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { ret > > > > > static inline void tdx_flush_tlb(struct kvm_vcpu *vcpu) {} > > > > > static inline int tdx_sept_tlb_remote_flush(struct kvm *kvm) { return 0; } > > > > > static inline void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level) {} > > > > > + > > > > > +static inline int tdx_vm_move_enc_context_from(struct kvm *kvm, u > > > > > + nsigned int source_fd) { return -EOPNOTSUPP; } > > > > > #endif > > > > > > > > > > #if defined(CONFIG_INTEL_TDX_HOST) && defined(CONFIG_KVM_SMM) > > > > > >
