| Message ID | 20190424160942.13567-3-brijesh.singh@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add AMD SEV guest live migration support | expand |
On 4/24/19 11:10 AM, Singh, Brijesh wrote: > The command is used for encrypting the guest memory region using the encryption > context created with KVM_SEV_SEND_START. > > 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> > --- > .../virtual/kvm/amd-memory-encryption.rst | 23 ++++ > arch/x86/kvm/svm.c | 128 +++++++++++++++++- > include/uapi/linux/kvm.h | 9 ++ > 3 files changed, 157 insertions(+), 3 deletions(-) > > diff --git a/Documentation/virtual/kvm/amd-memory-encryption.rst b/Documentation/virtual/kvm/amd-memory-encryption.rst > index 340ac4f87321..a0208e171489 100644 > --- a/Documentation/virtual/kvm/amd-memory-encryption.rst > +++ b/Documentation/virtual/kvm/amd-memory-encryption.rst > @@ -262,6 +262,29 @@ Returns: 0 on success, -negative on error > __u32 amd_cert_len; > }; > > +11. KVM_SEV_SEND_UPDATE_DATA > +---------------------------- > + > +The KVM_SEV_SEND_UPDATE_DATA command can be used by the hypervisor to encrypt the > +outgoing guest memory region with encryption context creating using KVM_SEV_SEND_START. with the encryption context created using... > + > +Parameters (in): struct kvm_sev_send_update_data > + > +Returns: 0 on success, -negative on error > + > +:: > + > + struct kvm_sev_launch_send_update_data { > + __u64 hdr_uaddr; /* userspace address containing the packet header */ > + __u32 hdr_len; > + > + __u64 guest_uaddr; /* the source memory region to be encrypted */ > + __u32 guest_len; > + > + __u64 trans_uaddr; /* the destition memory region */ > + __u32 trans_len; > + }; > + > References > ========== > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index 4c2a225ba546..a1cfd36d6195 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -418,6 +418,7 @@ enum { > > static unsigned int max_sev_asid; > static unsigned int min_sev_asid; > +static unsigned long me_mask; sev_me_mask ? > static unsigned long *sev_asid_bitmap; > #define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT) > > @@ -1216,15 +1217,21 @@ static int avic_ga_log_notifier(u32 ga_tag) > static __init int sev_hardware_setup(void) > { > struct sev_user_data_status *status; > + int eax, ebx; > int rc; > > - /* Maximum number of encrypted guests supported simultaneously */ > - max_sev_asid = cpuid_ecx(0x8000001F); > + /* > + * Query the memory encryption information. > + * EBX: Bit 0:5 Pagetable bit position used to indicate encryption (aka Cbit). > + * ECX: Maximum number of encrypted guests supported simultaneously. > + * EDX: Minimum ASID value that should be used for SEV guest. > + */ > + cpuid(0x8000001f, &eax, &ebx, &max_sev_asid, &min_sev_asid); > > if (!max_sev_asid) > return 1; > > - /* Minimum ASID value that should be used for SEV guest */ > + me_mask = 1UL << (ebx & 0x3f); > min_sev_asid = cpuid_edx(0x8000001F); You can remove this since you obtained it with the cpuid() call above. > > /* Initialize SEV ASID bitmap */ > @@ -7053,6 +7060,118 @@ static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) > return ret; > } > > +static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > + struct sev_data_send_update_data *data; > + struct kvm_sev_send_update_data params; > + void *hdr = NULL, *trans_data = NULL; > + struct page **guest_page = NULL; > + unsigned long n; > + int ret, offset; > + > + if (!sev_guest(kvm)) > + return -ENOTTY; > + > + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, > + sizeof(struct kvm_sev_send_update_data))) > + return -EFAULT; > + > + data = kzalloc(sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + /* userspace wants to query either header or trans length */ > + if (!params.trans_len || !params.hdr_len) > + goto cmd; > + > + ret = -EINVAL; > + if (!params.trans_uaddr || !params.guest_uaddr || > + !params.guest_len || !params.hdr_uaddr) > + goto e_free; > + > + /* Check if we are crossing the page boundry */ > + ret = -EINVAL; > + offset = params.guest_uaddr & (PAGE_SIZE - 1); > + if ((params.guest_len + offset > PAGE_SIZE)) > + goto e_free; > + > + ret = -ENOMEM; > + hdr = kmalloc(params.hdr_len, GFP_KERNEL); > + if (!hdr) > + goto e_free; > + > + data->hdr_address = __psp_pa(hdr); > + data->hdr_len = params.hdr_len; > + > + ret = -ENOMEM; > + trans_data = kmalloc(params.trans_len, GFP_KERNEL); > + if (!trans_data) > + goto e_free; > + > + data->trans_address = __psp_pa(trans_data); > + data->trans_len = params.trans_len; > + > + /* Pin guest memory */ > + ret = -EFAULT; > + guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, > + PAGE_SIZE, &n, 0); > + if (!guest_page) > + goto e_free; > + > + data->guest_address = __sme_page_pa(guest_page[0]) + offset; If the C-bit needs to be set regardless below, then you don't need the __sme version of this. > + data->guest_len = params.guest_len; > + > + /* > + * The SEND_UPDATE_DATA command requires C-bit to be always set. > + * The __sme_page_pa() takes care of setting the C-bit only when SME > + * is enabled on the host. But we need to set the C-bit regarless of regardless Thanks, Tom > + * the SME state. > + */ > + data->guest_address |= me_mask; > + > + /* flush the caches to ensure that DRAM has recent contents */ > + sev_clflush_pages(guest_page, 1); > + > +cmd: > + data->handle = sev->handle; > + ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp->error); > + > + /* userspace asked for header or trans length and FW responded with data */ > + if (!params.trans_len || !params.hdr_len) { > + params.hdr_len = data->hdr_len; > + params.trans_len = data->trans_len; > + goto done; > + } > + > + if (ret) > + goto e_unpin; > + > + /* copy transport buffer to user space */ > + if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, > + trans_data, params.trans_len)) { > + ret = -EFAULT; > + goto e_unpin; > + } > + > + /* copy packet header to userspace */ > + if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, params.hdr_len)) > + ret = -EFAULT; > + > +e_unpin: > + sev_unpin_memory(kvm, guest_page, n); > +done: > + if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, > + sizeof(struct kvm_sev_send_update_data))) > + ret = -EFAULT; > +e_free: > + kfree(data); > + kfree(trans_data); > + kfree(hdr); > + > + return ret; > +} > + > static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > { > struct kvm_sev_cmd sev_cmd; > @@ -7097,6 +7216,9 @@ static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > case KVM_SEV_SEND_START: > r = sev_send_start(kvm, &sev_cmd); > break; > + case KVM_SEV_SEND_UPDATE_DATA: > + r = sev_send_update_data(kvm, &sev_cmd); > + break; > default: > r = -EINVAL; > goto out; > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index f425418bec13..0bee91bba329 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -1532,6 +1532,15 @@ struct kvm_sev_send_start { > __u32 session_len; > }; > > +struct kvm_sev_send_update_data { > + __u64 hdr_uaddr; > + __u32 hdr_len; > + __u64 guest_uaddr; > + __u32 guest_len; > + __u64 trans_uaddr; > + __u32 trans_len; > +}; > + > #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) > #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) > #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2) >
On 4/26/19 3:31 PM, Lendacky, Thomas wrote: ... >> >> static unsigned int max_sev_asid; >> static unsigned int min_sev_asid; >> +static unsigned long me_mask; > > sev_me_mask ? > Agreed. >> static unsigned long *sev_asid_bitmap; >> #define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT) >> >> @@ -1216,15 +1217,21 @@ static int avic_ga_log_notifier(u32 ga_tag) >> static __init int sev_hardware_setup(void) >> { >> struct sev_user_data_status *status; >> + int eax, ebx; >> int rc; >> >> - /* Maximum number of encrypted guests supported simultaneously */ >> - max_sev_asid = cpuid_ecx(0x8000001F); >> + /* >> + * Query the memory encryption information. >> + * EBX: Bit 0:5 Pagetable bit position used to indicate encryption (aka Cbit). >> + * ECX: Maximum number of encrypted guests supported simultaneously. >> + * EDX: Minimum ASID value that should be used for SEV guest. >> + */ >> + cpuid(0x8000001f, &eax, &ebx, &max_sev_asid, &min_sev_asid); >> >> if (!max_sev_asid) >> return 1; >> >> - /* Minimum ASID value that should be used for SEV guest */ >> + me_mask = 1UL << (ebx & 0x3f); >> min_sev_asid = cpuid_edx(0x8000001F); > > You can remove this since you obtained it with the cpuid() call above. > I thought I removed it but.. I will take care in next rev. >> >> /* Initialize SEV ASID bitmap */ >> @@ -7053,6 +7060,118 @@ static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) >> return ret; >> } >> >> +static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) >> +{ >> + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; >> + struct sev_data_send_update_data *data; >> + struct kvm_sev_send_update_data params; >> + void *hdr = NULL, *trans_data = NULL; >> + struct page **guest_page = NULL; >> + unsigned long n; >> + int ret, offset; >> + >> + if (!sev_guest(kvm)) >> + return -ENOTTY; >> + >> + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, >> + sizeof(struct kvm_sev_send_update_data))) >> + return -EFAULT; >> + >> + data = kzalloc(sizeof(*data), GFP_KERNEL); >> + if (!data) >> + return -ENOMEM; >> + >> + /* userspace wants to query either header or trans length */ >> + if (!params.trans_len || !params.hdr_len) >> + goto cmd; >> + >> + ret = -EINVAL; >> + if (!params.trans_uaddr || !params.guest_uaddr || >> + !params.guest_len || !params.hdr_uaddr) >> + goto e_free; >> + >> + /* Check if we are crossing the page boundry */ >> + ret = -EINVAL; >> + offset = params.guest_uaddr & (PAGE_SIZE - 1); >> + if ((params.guest_len + offset > PAGE_SIZE)) >> + goto e_free; >> + >> + ret = -ENOMEM; >> + hdr = kmalloc(params.hdr_len, GFP_KERNEL); >> + if (!hdr) >> + goto e_free; >> + >> + data->hdr_address = __psp_pa(hdr); >> + data->hdr_len = params.hdr_len; >> + >> + ret = -ENOMEM; >> + trans_data = kmalloc(params.trans_len, GFP_KERNEL); >> + if (!trans_data) >> + goto e_free; >> + >> + data->trans_address = __psp_pa(trans_data); >> + data->trans_len = params.trans_len; >> + >> + /* Pin guest memory */ >> + ret = -EFAULT; >> + guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, >> + PAGE_SIZE, &n, 0); >> + if (!guest_page) >> + goto e_free; >> + >> + data->guest_address = __sme_page_pa(guest_page[0]) + offset; > > If the C-bit needs to be set regardless below, then you don't need the > __sme version of this. > Noted.
diff --git a/Documentation/virtual/kvm/amd-memory-encryption.rst b/Documentation/virtual/kvm/amd-memory-encryption.rst index 340ac4f87321..a0208e171489 100644 --- a/Documentation/virtual/kvm/amd-memory-encryption.rst +++ b/Documentation/virtual/kvm/amd-memory-encryption.rst @@ -262,6 +262,29 @@ Returns: 0 on success, -negative on error __u32 amd_cert_len; }; +11. KVM_SEV_SEND_UPDATE_DATA +---------------------------- + +The KVM_SEV_SEND_UPDATE_DATA command can be used by the hypervisor to encrypt the +outgoing guest memory region with encryption context creating using KVM_SEV_SEND_START. + +Parameters (in): struct kvm_sev_send_update_data + +Returns: 0 on success, -negative on error + +:: + + struct kvm_sev_launch_send_update_data { + __u64 hdr_uaddr; /* userspace address containing the packet header */ + __u32 hdr_len; + + __u64 guest_uaddr; /* the source memory region to be encrypted */ + __u32 guest_len; + + __u64 trans_uaddr; /* the destition memory region */ + __u32 trans_len; + }; + References ========== diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 4c2a225ba546..a1cfd36d6195 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -418,6 +418,7 @@ enum { static unsigned int max_sev_asid; static unsigned int min_sev_asid; +static unsigned long me_mask; static unsigned long *sev_asid_bitmap; #define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT) @@ -1216,15 +1217,21 @@ static int avic_ga_log_notifier(u32 ga_tag) static __init int sev_hardware_setup(void) { struct sev_user_data_status *status; + int eax, ebx; int rc; - /* Maximum number of encrypted guests supported simultaneously */ - max_sev_asid = cpuid_ecx(0x8000001F); + /* + * Query the memory encryption information. + * EBX: Bit 0:5 Pagetable bit position used to indicate encryption (aka Cbit). + * ECX: Maximum number of encrypted guests supported simultaneously. + * EDX: Minimum ASID value that should be used for SEV guest. + */ + cpuid(0x8000001f, &eax, &ebx, &max_sev_asid, &min_sev_asid); if (!max_sev_asid) return 1; - /* Minimum ASID value that should be used for SEV guest */ + me_mask = 1UL << (ebx & 0x3f); min_sev_asid = cpuid_edx(0x8000001F); /* Initialize SEV ASID bitmap */ @@ -7053,6 +7060,118 @@ static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) return ret; } +static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + struct sev_data_send_update_data *data; + struct kvm_sev_send_update_data params; + void *hdr = NULL, *trans_data = NULL; + struct page **guest_page = NULL; + unsigned long n; + int ret, offset; + + if (!sev_guest(kvm)) + return -ENOTTY; + + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, + sizeof(struct kvm_sev_send_update_data))) + return -EFAULT; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + /* userspace wants to query either header or trans length */ + if (!params.trans_len || !params.hdr_len) + goto cmd; + + ret = -EINVAL; + if (!params.trans_uaddr || !params.guest_uaddr || + !params.guest_len || !params.hdr_uaddr) + goto e_free; + + /* Check if we are crossing the page boundry */ + ret = -EINVAL; + offset = params.guest_uaddr & (PAGE_SIZE - 1); + if ((params.guest_len + offset > PAGE_SIZE)) + goto e_free; + + ret = -ENOMEM; + hdr = kmalloc(params.hdr_len, GFP_KERNEL); + if (!hdr) + goto e_free; + + data->hdr_address = __psp_pa(hdr); + data->hdr_len = params.hdr_len; + + ret = -ENOMEM; + trans_data = kmalloc(params.trans_len, GFP_KERNEL); + if (!trans_data) + goto e_free; + + data->trans_address = __psp_pa(trans_data); + data->trans_len = params.trans_len; + + /* Pin guest memory */ + ret = -EFAULT; + guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, + PAGE_SIZE, &n, 0); + if (!guest_page) + goto e_free; + + data->guest_address = __sme_page_pa(guest_page[0]) + offset; + data->guest_len = params.guest_len; + + /* + * The SEND_UPDATE_DATA command requires C-bit to be always set. + * The __sme_page_pa() takes care of setting the C-bit only when SME + * is enabled on the host. But we need to set the C-bit regarless of + * the SME state. + */ + data->guest_address |= me_mask; + + /* flush the caches to ensure that DRAM has recent contents */ + sev_clflush_pages(guest_page, 1); + +cmd: + data->handle = sev->handle; + ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp->error); + + /* userspace asked for header or trans length and FW responded with data */ + if (!params.trans_len || !params.hdr_len) { + params.hdr_len = data->hdr_len; + params.trans_len = data->trans_len; + goto done; + } + + if (ret) + goto e_unpin; + + /* copy transport buffer to user space */ + if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, + trans_data, params.trans_len)) { + ret = -EFAULT; + goto e_unpin; + } + + /* copy packet header to userspace */ + if (copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, params.hdr_len)) + ret = -EFAULT; + +e_unpin: + sev_unpin_memory(kvm, guest_page, n); +done: + if (copy_to_user((void __user *)(uintptr_t)argp->data, ¶ms, + sizeof(struct kvm_sev_send_update_data))) + ret = -EFAULT; +e_free: + kfree(data); + kfree(trans_data); + kfree(hdr); + + return ret; +} + static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) { struct kvm_sev_cmd sev_cmd; @@ -7097,6 +7216,9 @@ static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) case KVM_SEV_SEND_START: r = sev_send_start(kvm, &sev_cmd); break; + case KVM_SEV_SEND_UPDATE_DATA: + r = sev_send_update_data(kvm, &sev_cmd); + break; default: r = -EINVAL; goto out; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index f425418bec13..0bee91bba329 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1532,6 +1532,15 @@ struct kvm_sev_send_start { __u32 session_len; }; +struct kvm_sev_send_update_data { + __u64 hdr_uaddr; + __u32 hdr_len; + __u64 guest_uaddr; + __u32 guest_len; + __u64 trans_uaddr; + __u32 trans_len; +}; + #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2)
The command is used for encrypting the guest memory region using the encryption context created with KVM_SEV_SEND_START. 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> --- .../virtual/kvm/amd-memory-encryption.rst | 23 ++++ arch/x86/kvm/svm.c | 128 +++++++++++++++++- include/uapi/linux/kvm.h | 9 ++ 3 files changed, 157 insertions(+), 3 deletions(-)