| Message ID | 20171020023413.122280-26-brijesh.singh@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Oct 19, 2017 at 09:34:00PM -0500, Brijesh Singh wrote: > The command initializes the SEV platform context and allocates a new ASID > for this guest from the SEV ASID pool. The firmware must be initialized > before we issue any guest launch commands to create a new memory encryption > context. > > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: "Radim Krčmář" <rkrcmar@redhat.com> > Cc: Joerg Roedel <joro@8bytes.org> > Cc: Borislav Petkov <bp@suse.de> > Cc: Tom Lendacky <thomas.lendacky@amd.com> > Cc: x86@kernel.org > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > --- > arch/x86/include/asm/kvm_host.h | 7 +++ > arch/x86/kvm/svm.c | 132 +++++++++++++++++++++++++++++++++++++++- > 2 files changed, 138 insertions(+), 1 deletion(-) ... > @@ -1167,10 +1187,18 @@ static __init int svm_hardware_setup(void) > return r; > } > > +static __exit void sev_hardware_unsetup(void) > +{ > + kfree(sev_asid_bitmap); > +} > + > static __exit void svm_hardware_unsetup(void) > { > int cpu; > > + if (svm_sev_enabled()) > + sev_hardware_unsetup(); Move that svm_sev_enabled() check into the function. > + > for_each_possible_cpu(cpu) > svm_cpu_uninit(cpu); > > @@ -1361,6 +1389,9 @@ static void init_vmcb(struct vcpu_svm *svm) > svm->vmcb->control.int_ctl |= V_GIF_ENABLE_MASK; > } > > + if (sev_guest(svm->vcpu.kvm)) > + svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; > + > mark_all_dirty(svm->vmcb); > > enable_gif(svm); > @@ -1443,6 +1474,28 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) > return 0; > } > > +static void sev_asid_free(struct kvm *kvm) > +{ > + struct kvm_sev_info *sev = &kvm->arch.sev_info; > + int pos, asid; > + > + if (!svm_sev_enabled()) > + return; You're already checking !sev_guest() below - no need to do the svm_sev_enabled() check again. > + > + asid = sev->asid; > + pos = asid - 1; > + clear_bit(pos, sev_asid_bitmap); > +} > + > +static void sev_vm_destroy(struct kvm *kvm) > +{ > + if (!sev_guest(kvm)) > + return; > + > + sev_platform_shutdown(NULL); > + sev_asid_free(kvm); > +} > + > static void avic_vm_destroy(struct kvm *kvm) > { > unsigned long flags; > @@ -1461,6 +1514,12 @@ static void avic_vm_destroy(struct kvm *kvm) > spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); > } > > +static void svm_vm_destroy(struct kvm *kvm) > +{ > + avic_vm_destroy(kvm); > + sev_vm_destroy(kvm); > +} > + > static int avic_vm_init(struct kvm *kvm) > { > unsigned long flags; > @@ -5427,6 +5486,75 @@ static void svm_setup_mce(struct kvm_vcpu *vcpu) > vcpu->arch.mcg_cap &= 0x1ff; > } > > +static int sev_asid_new(void) > +{ > + int pos; > + > + if (!svm_sev_enabled()) > + return -EINVAL; You already checked that in svm_mem_enc_op() - no need to do it again. > + pos = find_first_zero_bit(sev_asid_bitmap, max_sev_asid); > + if (pos >= max_sev_asid) > + return -EBUSY; > + > + set_bit(pos, sev_asid_bitmap); > + return pos + 1; > +} > + > +static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) > +{ > + struct kvm_sev_info *sev = &kvm->arch.sev_info; > + int asid, ret; > + > + ret = sev_platform_init(NULL, &argp->error); > + if (ret) > + return ret; > + > + ret = -EBUSY; > + asid = sev_asid_new(); This operation is cheaper so do it first and then sev_platform_init() so that in case sev_asid_new() fails, you don't "toggle" the PSP unnecessarily. > + if (asid < 0) > + goto e_shutdown; > + > + sev->active = true; > + sev->asid = asid; > + > + return 0; > + > +e_shutdown: > + sev_platform_shutdown(&argp->error); > + return ret; > +} > +
On 10/27/17 3:24 PM, Borislav Petkov wrote: ... >> + >> static __exit void svm_hardware_unsetup(void) >> { >> int cpu; >> >> + if (svm_sev_enabled()) >> + sev_hardware_unsetup(); > Move that svm_sev_enabled() check into the function. Sure, I will remove the check. > >> + >> for_each_possible_cpu(cpu) >> svm_cpu_uninit(cpu); >> >> @@ -1361,6 +1389,9 @@ static void init_vmcb(struct vcpu_svm *svm) >> svm->vmcb->control.int_ctl |= V_GIF_ENABLE_MASK; >> } >> >> + if (sev_guest(svm->vcpu.kvm)) >> + svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; >> + >> mark_all_dirty(svm->vmcb); >> >> enable_gif(svm); >> @@ -1443,6 +1474,28 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) >> return 0; >> } >> >> +static void sev_asid_free(struct kvm *kvm) >> +{ >> + struct kvm_sev_info *sev = &kvm->arch.sev_info; >> + int pos, asid; >> + >> + if (!svm_sev_enabled()) >> + return; > You're already checking !sev_guest() below - no need to do the > svm_sev_enabled() check again. Agreed, I will remove it. >> +{ >> + int pos; >> + >> + if (!svm_sev_enabled()) >> + return -EINVAL; > You already checked that in svm_mem_enc_op() - no need to do it again. Agreed, I will remove it > >> + pos = find_first_zero_bit(sev_asid_bitmap, max_sev_asid); >> + if (pos >= max_sev_asid) >> + return -EBUSY; >> + >> + set_bit(pos, sev_asid_bitmap); >> + return pos + 1; >> +} >> + >> +static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) >> +{ >> + struct kvm_sev_info *sev = &kvm->arch.sev_info; >> + int asid, ret; >> + >> + ret = sev_platform_init(NULL, &argp->error); >> + if (ret) >> + return ret; >> + >> + ret = -EBUSY; >> + asid = sev_asid_new(); > This operation is cheaper so do it first and then sev_platform_init() > so that in case sev_asid_new() fails, you don't "toggle" the PSP > unnecessarily. Sure, I will change the order.
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3af074452b2b..b8837cff22ec 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -747,6 +747,11 @@ enum kvm_irqchip_mode { KVM_IRQCHIP_SPLIT, /* created with KVM_CAP_SPLIT_IRQCHIP */ }; +struct kvm_sev_info { + bool active; /* SEV enabled guest */ + unsigned int asid; /* ASID used for this guest */ +}; + struct kvm_arch { unsigned int n_used_mmu_pages; unsigned int n_requested_mmu_pages; @@ -834,6 +839,8 @@ struct kvm_arch { bool x2apic_format; bool x2apic_broadcast_quirk_disabled; + + struct kvm_sev_info sev_info; }; struct kvm_vm_stat { diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index d4b62536e305..d496063ccd78 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -37,6 +37,8 @@ #include <linux/amd-iommu.h> #include <linux/hashtable.h> #include <linux/frame.h> +#include <linux/psp-sev.h> +#include <linux/file.h> #include <asm/apic.h> #include <asm/perf_event.h> @@ -324,6 +326,19 @@ enum { #define VMCB_AVIC_APIC_BAR_MASK 0xFFFFFFFFFF000ULL static unsigned int max_sev_asid; +static unsigned long *sev_asid_bitmap; + +static inline bool svm_sev_enabled(void) +{ + return max_sev_asid; +} + +static inline bool sev_guest(struct kvm *kvm) +{ + struct kvm_sev_info *sev = &kvm->arch.sev_info; + + return sev->active; +} static inline void mark_all_dirty(struct vmcb *vmcb) { @@ -1063,6 +1078,11 @@ static int avic_ga_log_notifier(u32 ga_tag) static __init void sev_hardware_setup(void) { max_sev_asid = cpuid_ecx(0x8000001F); + + /* Initialize SEV ASID bitmap */ + if (max_sev_asid) + sev_asid_bitmap = kcalloc(BITS_TO_LONGS(max_sev_asid), + sizeof(unsigned long), GFP_KERNEL); } static __init int svm_hardware_setup(void) @@ -1167,10 +1187,18 @@ static __init int svm_hardware_setup(void) return r; } +static __exit void sev_hardware_unsetup(void) +{ + kfree(sev_asid_bitmap); +} + static __exit void svm_hardware_unsetup(void) { int cpu; + if (svm_sev_enabled()) + sev_hardware_unsetup(); + for_each_possible_cpu(cpu) svm_cpu_uninit(cpu); @@ -1361,6 +1389,9 @@ static void init_vmcb(struct vcpu_svm *svm) svm->vmcb->control.int_ctl |= V_GIF_ENABLE_MASK; } + if (sev_guest(svm->vcpu.kvm)) + svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ENABLE; + mark_all_dirty(svm->vmcb); enable_gif(svm); @@ -1443,6 +1474,28 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) return 0; } +static void sev_asid_free(struct kvm *kvm) +{ + struct kvm_sev_info *sev = &kvm->arch.sev_info; + int pos, asid; + + if (!svm_sev_enabled()) + return; + + asid = sev->asid; + pos = asid - 1; + clear_bit(pos, sev_asid_bitmap); +} + +static void sev_vm_destroy(struct kvm *kvm) +{ + if (!sev_guest(kvm)) + return; + + sev_platform_shutdown(NULL); + sev_asid_free(kvm); +} + static void avic_vm_destroy(struct kvm *kvm) { unsigned long flags; @@ -1461,6 +1514,12 @@ static void avic_vm_destroy(struct kvm *kvm) spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); } +static void svm_vm_destroy(struct kvm *kvm) +{ + avic_vm_destroy(kvm); + sev_vm_destroy(kvm); +} + static int avic_vm_init(struct kvm *kvm) { unsigned long flags; @@ -5427,6 +5486,75 @@ static void svm_setup_mce(struct kvm_vcpu *vcpu) vcpu->arch.mcg_cap &= 0x1ff; } +static int sev_asid_new(void) +{ + int pos; + + if (!svm_sev_enabled()) + return -EINVAL; + + pos = find_first_zero_bit(sev_asid_bitmap, max_sev_asid); + if (pos >= max_sev_asid) + return -EBUSY; + + set_bit(pos, sev_asid_bitmap); + return pos + 1; +} + +static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_info *sev = &kvm->arch.sev_info; + int asid, ret; + + ret = sev_platform_init(NULL, &argp->error); + if (ret) + return ret; + + ret = -EBUSY; + asid = sev_asid_new(); + if (asid < 0) + goto e_shutdown; + + sev->active = true; + sev->asid = asid; + + return 0; + +e_shutdown: + sev_platform_shutdown(&argp->error); + return ret; +} + +static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) +{ + struct kvm_sev_cmd sev_cmd; + int r; + + if (!svm_sev_enabled()) + return -ENOTTY; + + if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) + return -EFAULT; + + mutex_lock(&kvm->lock); + + switch (sev_cmd.id) { + case KVM_SEV_INIT: + r = sev_guest_init(kvm, &sev_cmd); + break; + default: + r = -EINVAL; + goto out; + } + + if (copy_to_user(argp, &sev_cmd, sizeof(struct kvm_sev_cmd))) + r = -EFAULT; + +out: + mutex_unlock(&kvm->lock); + return r; +} + static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .cpu_has_kvm_support = has_svm, .disabled_by_bios = is_disabled, @@ -5443,7 +5571,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .vcpu_reset = svm_vcpu_reset, .vm_init = avic_vm_init, - .vm_destroy = avic_vm_destroy, + .vm_destroy = svm_vm_destroy, .prepare_guest_switch = svm_prepare_guest_switch, .vcpu_load = svm_vcpu_load, @@ -5537,6 +5665,8 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .deliver_posted_interrupt = svm_deliver_avic_intr, .update_pi_irte = svm_update_pi_irte, .setup_mce = svm_setup_mce, + + .mem_enc_op = svm_mem_enc_op, }; static int __init svm_init(void)
The command initializes the SEV platform context and allocates a new ASID for this guest from the SEV ASID pool. The firmware must be initialized before we issue any guest launch commands to create a new memory encryption context. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Borislav Petkov <bp@suse.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> --- arch/x86/include/asm/kvm_host.h | 7 +++ arch/x86/kvm/svm.c | 132 +++++++++++++++++++++++++++++++++++++++- 2 files changed, 138 insertions(+), 1 deletion(-)