diff options
Diffstat (limited to 'target/i386/sev.c')
| -rw-r--r-- | target/i386/sev.c | 850 |
1 files changed, 772 insertions, 78 deletions
diff --git a/target/i386/sev.c b/target/i386/sev.c index 1a12f0671c..1057b8ab2c 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -41,7 +41,9 @@ #include "confidential-guest.h" #include "hw/i386/pc.h" #include "system/address-spaces.h" +#include "hw/i386/e820_memory_layout.h" #include "qemu/queue.h" +#include "qemu/cutils.h" OBJECT_DECLARE_TYPE(SevCommonState, SevCommonStateClass, SEV_COMMON) OBJECT_DECLARE_TYPE(SevGuestState, SevCommonStateClass, SEV_GUEST) @@ -50,6 +52,15 @@ OBJECT_DECLARE_TYPE(SevSnpGuestState, SevCommonStateClass, SEV_SNP_GUEST) /* hard code sha256 digest size */ #define HASH_SIZE 32 +/* Hard coded GPA that KVM uses for the VMSA */ +#define KVM_VMSA_GPA 0xFFFFFFFFF000 + +/* Convert between SEV-ES VMSA and SegmentCache flags/attributes */ +#define FLAGS_VMSA_TO_SEGCACHE(flags) \ + ((((flags) & 0xff00) << 12) | (((flags) & 0xff) << 8)) +#define FLAGS_SEGCACHE_TO_VMSA(flags) \ + ((((flags) & 0xff00) >> 8) | (((flags) & 0xf00000) >> 12)) + typedef struct QEMU_PACKED SevHashTableEntry { QemuUUID guid; uint16_t len; @@ -89,6 +100,14 @@ typedef struct QEMU_PACKED SevHashTableDescriptor { uint32_t size; } SevHashTableDescriptor; +typedef struct SevLaunchVmsa { + QTAILQ_ENTRY(SevLaunchVmsa) next; + + uint16_t cpu_index; + uint64_t gpa; + struct sev_es_save_area vmsa; +} SevLaunchVmsa; + struct SevCommonState { X86ConfidentialGuest parent_obj; @@ -99,6 +118,8 @@ struct SevCommonState { uint32_t cbitpos; uint32_t reduced_phys_bits; bool kernel_hashes; + uint64_t sev_features; + uint64_t supported_sev_features; /* runtime state */ uint8_t api_major; @@ -107,9 +128,7 @@ struct SevCommonState { int sev_fd; SevState state; - uint32_t reset_cs; - uint32_t reset_ip; - bool reset_data_valid; + QTAILQ_HEAD(, SevLaunchVmsa) launch_vmsa; }; struct SevCommonStateClass { @@ -122,7 +141,8 @@ struct SevCommonStateClass { Error **errp); int (*launch_start)(SevCommonState *sev_common); void (*launch_finish)(SevCommonState *sev_common); - int (*launch_update_data)(SevCommonState *sev_common, hwaddr gpa, uint8_t *ptr, size_t len); + int (*launch_update_data)(SevCommonState *sev_common, hwaddr gpa, + uint8_t *ptr, size_t len, Error **errp); int (*kvm_init)(ConfidentialGuestSupport *cgs, Error **errp); }; @@ -363,6 +383,288 @@ static struct RAMBlockNotifier sev_ram_notifier = { .ram_block_removed = sev_ram_block_removed, }; +static void sev_apply_cpu_context(CPUState *cpu) +{ + SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); + X86CPU *x86; + CPUX86State *env; + struct SevLaunchVmsa *launch_vmsa; + + /* See if an initial VMSA has been provided for this CPU */ + QTAILQ_FOREACH(launch_vmsa, &sev_common->launch_vmsa, next) + { + if (cpu->cpu_index == launch_vmsa->cpu_index) { + x86 = X86_CPU(cpu); + env = &x86->env; + + /* + * Ideally we would provide the VMSA directly to kvm which would + * ensure that the resulting initial VMSA measurement which is + * calculated during KVM_SEV_LAUNCH_UPDATE_VMSA is calculated from + * exactly what we provide here. Currently this is not possible so + * we need to copy the parts of the VMSA structure that we currently + * support into the CPU state. + */ + cpu_load_efer(env, launch_vmsa->vmsa.efer); + cpu_x86_update_cr4(env, launch_vmsa->vmsa.cr4); + cpu_x86_update_cr0(env, launch_vmsa->vmsa.cr0); + cpu_x86_update_cr3(env, launch_vmsa->vmsa.cr3); + env->xcr0 = launch_vmsa->vmsa.xcr0; + env->pat = launch_vmsa->vmsa.g_pat; + + cpu_x86_load_seg_cache( + env, R_CS, launch_vmsa->vmsa.cs.selector, + launch_vmsa->vmsa.cs.base, launch_vmsa->vmsa.cs.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.cs.attrib)); + cpu_x86_load_seg_cache( + env, R_DS, launch_vmsa->vmsa.ds.selector, + launch_vmsa->vmsa.ds.base, launch_vmsa->vmsa.ds.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.ds.attrib)); + cpu_x86_load_seg_cache( + env, R_ES, launch_vmsa->vmsa.es.selector, + launch_vmsa->vmsa.es.base, launch_vmsa->vmsa.es.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.es.attrib)); + cpu_x86_load_seg_cache( + env, R_FS, launch_vmsa->vmsa.fs.selector, + launch_vmsa->vmsa.fs.base, launch_vmsa->vmsa.fs.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.fs.attrib)); + cpu_x86_load_seg_cache( + env, R_GS, launch_vmsa->vmsa.gs.selector, + launch_vmsa->vmsa.gs.base, launch_vmsa->vmsa.gs.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.gs.attrib)); + cpu_x86_load_seg_cache( + env, R_SS, launch_vmsa->vmsa.ss.selector, + launch_vmsa->vmsa.ss.base, launch_vmsa->vmsa.ss.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.ss.attrib)); + + env->gdt.base = launch_vmsa->vmsa.gdtr.base; + env->gdt.limit = launch_vmsa->vmsa.gdtr.limit; + env->gdt.flags = + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.gdtr.attrib); + env->idt.base = launch_vmsa->vmsa.idtr.base; + env->idt.limit = launch_vmsa->vmsa.idtr.limit; + env->idt.flags = + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.idtr.attrib); + + cpu_x86_load_seg_cache( + env, R_LDTR, launch_vmsa->vmsa.ldtr.selector, + launch_vmsa->vmsa.ldtr.base, launch_vmsa->vmsa.ldtr.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.ldtr.attrib)); + cpu_x86_load_seg_cache( + env, R_TR, launch_vmsa->vmsa.tr.selector, + launch_vmsa->vmsa.ldtr.base, launch_vmsa->vmsa.tr.limit, + FLAGS_VMSA_TO_SEGCACHE(launch_vmsa->vmsa.tr.attrib)); + + env->dr[6] = launch_vmsa->vmsa.dr6; + env->dr[7] = launch_vmsa->vmsa.dr7; + + env->regs[R_EAX] = launch_vmsa->vmsa.rax; + env->regs[R_ECX] = launch_vmsa->vmsa.rcx; + env->regs[R_EDX] = launch_vmsa->vmsa.rdx; + env->regs[R_EBX] = launch_vmsa->vmsa.rbx; + env->regs[R_ESP] = launch_vmsa->vmsa.rsp; + env->regs[R_EBP] = launch_vmsa->vmsa.rbp; + env->regs[R_ESI] = launch_vmsa->vmsa.rsi; + env->regs[R_EDI] = launch_vmsa->vmsa.rdi; +#ifdef TARGET_X86_64 + env->regs[R_R8] = launch_vmsa->vmsa.r8; + env->regs[R_R9] = launch_vmsa->vmsa.r9; + env->regs[R_R10] = launch_vmsa->vmsa.r10; + env->regs[R_R11] = launch_vmsa->vmsa.r11; + env->regs[R_R12] = launch_vmsa->vmsa.r12; + env->regs[R_R13] = launch_vmsa->vmsa.r13; + env->regs[R_R14] = launch_vmsa->vmsa.r14; + env->regs[R_R15] = launch_vmsa->vmsa.r15; +#endif + env->eip = launch_vmsa->vmsa.rip; + env->eflags = launch_vmsa->vmsa.rflags; + + cpu_set_fpuc(env, launch_vmsa->vmsa.x87_fcw); + env->mxcsr = launch_vmsa->vmsa.mxcsr; + + break; + } + } +} + +static int check_sev_features(SevCommonState *sev_common, uint64_t sev_features, + Error **errp) +{ + /* + * Ensure SEV_FEATURES is configured for correct SEV hardware and that + * the requested features are supported. If SEV-SNP is enabled then + * that feature must be enabled, otherwise it must be cleared. + */ + if (sev_snp_enabled() && !(sev_features & SVM_SEV_FEAT_SNP_ACTIVE)) { + error_setg( + errp, + "%s: SEV_SNP is enabled but is not enabled in VMSA sev_features", + __func__); + return -1; + } else if (!sev_snp_enabled() && + (sev_features & SVM_SEV_FEAT_SNP_ACTIVE)) { + error_setg( + errp, + "%s: SEV_SNP is not enabled but is enabled in VMSA sev_features", + __func__); + return -1; + } + if (sev_features & ~sev_common->supported_sev_features) { + error_setg(errp, + "%s: VMSA contains unsupported sev_features: %lX, " + "supported features: %lX", + __func__, sev_features, sev_common->supported_sev_features); + return -1; + } + return 0; +} + +static int check_vmsa_supported(SevCommonState *sev_common, hwaddr gpa, + const struct sev_es_save_area *vmsa, + Error **errp) +{ + struct sev_es_save_area vmsa_check; + + /* + * KVM always populates the VMSA at a fixed GPA which cannot be modified + * from userspace. Specifying a different GPA will not prevent the guest + * from starting but will cause the launch measurement to be different + * from expected. Therefore check that the provided GPA matches the KVM + * hardcoded value. + */ + if (gpa != KVM_VMSA_GPA) { + error_setg(errp, + "%s: The VMSA GPA must be %lX but is specified as %lX", + __func__, KVM_VMSA_GPA, gpa); + return -1; + } + + /* + * Clear all supported fields so we can then check the entire structure + * is zero. + */ + memcpy(&vmsa_check, vmsa, sizeof(struct sev_es_save_area)); + memset(&vmsa_check.es, 0, sizeof(vmsa_check.es)); + memset(&vmsa_check.cs, 0, sizeof(vmsa_check.cs)); + memset(&vmsa_check.ss, 0, sizeof(vmsa_check.ss)); + memset(&vmsa_check.ds, 0, sizeof(vmsa_check.ds)); + memset(&vmsa_check.fs, 0, sizeof(vmsa_check.fs)); + memset(&vmsa_check.gs, 0, sizeof(vmsa_check.gs)); + memset(&vmsa_check.gdtr, 0, sizeof(vmsa_check.gdtr)); + memset(&vmsa_check.idtr, 0, sizeof(vmsa_check.idtr)); + memset(&vmsa_check.ldtr, 0, sizeof(vmsa_check.ldtr)); + memset(&vmsa_check.tr, 0, sizeof(vmsa_check.tr)); + vmsa_check.efer = 0; + vmsa_check.cr0 = 0; + vmsa_check.cr3 = 0; + vmsa_check.cr4 = 0; + vmsa_check.xcr0 = 0; + vmsa_check.dr6 = 0; + vmsa_check.dr7 = 0; + vmsa_check.rax = 0; + vmsa_check.rcx = 0; + vmsa_check.rdx = 0; + vmsa_check.rbx = 0; + vmsa_check.rsp = 0; + vmsa_check.rbp = 0; + vmsa_check.rsi = 0; + vmsa_check.rdi = 0; + vmsa_check.r8 = 0; + vmsa_check.r9 = 0; + vmsa_check.r10 = 0; + vmsa_check.r11 = 0; + vmsa_check.r12 = 0; + vmsa_check.r13 = 0; + vmsa_check.r14 = 0; + vmsa_check.r15 = 0; + vmsa_check.rip = 0; + vmsa_check.rflags = 0; + + vmsa_check.g_pat = 0; + vmsa_check.xcr0 = 0; + + vmsa_check.x87_fcw = 0; + vmsa_check.mxcsr = 0; + + if (check_sev_features(sev_common, vmsa_check.sev_features, errp) < 0) { + return -1; + } + vmsa_check.sev_features = 0; + + if (!buffer_is_zero(&vmsa_check, sizeof(vmsa_check))) { + error_setg(errp, + "%s: The VMSA contains fields that are not " + "synchronized with KVM. Continuing would result in " + "either unpredictable guest behavior, or a " + "mismatched launch measurement.", + __func__); + return -1; + } + return 0; +} + +static int sev_set_cpu_context(uint16_t cpu_index, const void *ctx, + uint32_t ctx_len, hwaddr gpa, Error **errp) +{ + SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); + SevLaunchVmsa *launch_vmsa; + CPUState *cpu; + bool exists = false; + + /* + * Setting the CPU context is only supported for SEV-ES and SEV-SNP. The + * context buffer will contain a sev_es_save_area from the Linux kernel + * which is defined by "Table B-4. VMSA Layout, State Save Area for SEV-ES" + * in the AMD64 APM, Volume 2. + */ + + if (!sev_es_enabled()) { + error_setg(errp, "SEV: unable to set CPU context: Not supported"); + return -1; + } + + if (ctx_len < sizeof(struct sev_es_save_area)) { + error_setg(errp, "SEV: unable to set CPU context: " + "Invalid context provided"); + return -1; + } + + cpu = qemu_get_cpu(cpu_index); + if (!cpu) { + error_setg(errp, "SEV: unable to set CPU context for out of bounds " + "CPU index %d", cpu_index); + return -1; + } + + /* + * If the context of this VP has already been set then replace it with the + * new context. + */ + QTAILQ_FOREACH(launch_vmsa, &sev_common->launch_vmsa, next) + { + if (cpu_index == launch_vmsa->cpu_index) { + launch_vmsa->gpa = gpa; + memcpy(&launch_vmsa->vmsa, ctx, sizeof(launch_vmsa->vmsa)); + exists = true; + break; + } + } + + if (!exists) { + /* New VP context */ + launch_vmsa = g_new0(SevLaunchVmsa, 1); + memcpy(&launch_vmsa->vmsa, ctx, sizeof(launch_vmsa->vmsa)); + launch_vmsa->cpu_index = cpu_index; + launch_vmsa->gpa = gpa; + QTAILQ_INSERT_TAIL(&sev_common->launch_vmsa, launch_vmsa, next); + } + + /* Synchronise the VMSA with the current CPU state */ + sev_apply_cpu_context(cpu); + + return 0; +} + bool sev_enabled(void) { @@ -970,9 +1272,8 @@ sev_snp_adjust_cpuid_features(X86ConfidentialGuest *cg, uint32_t feature, uint32 return value; } -static int -sev_launch_update_data(SevCommonState *sev_common, hwaddr gpa, - uint8_t *addr, size_t len) +static int sev_launch_update_data(SevCommonState *sev_common, hwaddr gpa, + uint8_t *addr, size_t len, Error **errp) { int ret, fw_error; struct kvm_sev_launch_update_data update; @@ -987,8 +1288,8 @@ sev_launch_update_data(SevCommonState *sev_common, hwaddr gpa, ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_UPDATE_DATA, &update, &fw_error); if (ret) { - error_report("%s: LAUNCH_UPDATE ret=%d fw_error=%d '%s'", - __func__, ret, fw_error, fw_error_to_str(fw_error)); + error_setg(errp, "%s: LAUNCH_UPDATE ret=%d fw_error=%d '%s'", __func__, + ret, fw_error, fw_error_to_str(fw_error)); } return ret; @@ -998,6 +1299,16 @@ static int sev_launch_update_vmsa(SevGuestState *sev_guest) { int ret, fw_error; + CPUState *cpu; + + /* + * The initial CPU state is measured as part of KVM_SEV_LAUNCH_UPDATE_VMSA. + * Synchronise the CPU state to any provided launch VMSA structures. + */ + CPU_FOREACH(cpu) { + sev_apply_cpu_context(cpu); + } + ret = sev_ioctl(SEV_COMMON(sev_guest)->sev_fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL, &fw_error); @@ -1116,8 +1427,8 @@ sev_launch_finish(SevCommonState *sev_common) migrate_add_blocker(&sev_mig_blocker, &error_fatal); } -static int -snp_launch_update_data(uint64_t gpa, void *hva, size_t len, int type) +static int snp_launch_update_data(uint64_t gpa, void *hva, size_t len, + int type, Error **errp) { SevLaunchUpdateData *data; @@ -1132,23 +1443,21 @@ snp_launch_update_data(uint64_t gpa, void *hva, size_t len, int type) return 0; } -static int -sev_snp_launch_update_data(SevCommonState *sev_common, hwaddr gpa, - uint8_t *ptr, size_t len) +static int sev_snp_launch_update_data(SevCommonState *sev_common, hwaddr gpa, + uint8_t *ptr, size_t len, Error **errp) { - int ret = snp_launch_update_data(gpa, ptr, len, - KVM_SEV_SNP_PAGE_TYPE_NORMAL); - return ret; + return snp_launch_update_data(gpa, ptr, len, + KVM_SEV_SNP_PAGE_TYPE_NORMAL, errp); } static int sev_snp_cpuid_info_fill(SnpCpuidInfo *snp_cpuid_info, - const KvmCpuidInfo *kvm_cpuid_info) + const KvmCpuidInfo *kvm_cpuid_info, Error **errp) { size_t i; if (kvm_cpuid_info->cpuid.nent > SNP_CPUID_FUNCTION_MAXCOUNT) { - error_report("SEV-SNP: CPUID entry count (%d) exceeds max (%d)", + error_setg(errp, "SEV-SNP: CPUID entry count (%d) exceeds max (%d)", kvm_cpuid_info->cpuid.nent, SNP_CPUID_FUNCTION_MAXCOUNT); return -1; } @@ -1190,8 +1499,8 @@ sev_snp_cpuid_info_fill(SnpCpuidInfo *snp_cpuid_info, return 0; } -static int -snp_launch_update_cpuid(uint32_t cpuid_addr, void *hva, size_t cpuid_len) +static int snp_launch_update_cpuid(uint32_t cpuid_addr, void *hva, + size_t cpuid_len, Error **errp) { KvmCpuidInfo kvm_cpuid_info = {0}; SnpCpuidInfo snp_cpuid_info; @@ -1208,26 +1517,25 @@ snp_launch_update_cpuid(uint32_t cpuid_addr, void *hva, size_t cpuid_len) } while (ret == -E2BIG); if (ret) { - error_report("SEV-SNP: unable to query CPUID values for CPU: '%s'", - strerror(-ret)); - return 1; + error_setg(errp, "SEV-SNP: unable to query CPUID values for CPU: '%s'", + strerror(-ret)); + return -1; } - ret = sev_snp_cpuid_info_fill(&snp_cpuid_info, &kvm_cpuid_info); - if (ret) { - error_report("SEV-SNP: failed to generate CPUID table information"); - return 1; + ret = sev_snp_cpuid_info_fill(&snp_cpuid_info, &kvm_cpuid_info, errp); + if (ret < 0) { + return -1; } memcpy(hva, &snp_cpuid_info, sizeof(snp_cpuid_info)); return snp_launch_update_data(cpuid_addr, hva, cpuid_len, - KVM_SEV_SNP_PAGE_TYPE_CPUID); + KVM_SEV_SNP_PAGE_TYPE_CPUID, errp); } -static int -snp_launch_update_kernel_hashes(SevSnpGuestState *sev_snp, uint32_t addr, - void *hva, uint32_t len) +static int snp_launch_update_kernel_hashes(SevSnpGuestState *sev_snp, + uint32_t addr, void *hva, + uint32_t len, Error **errp) { int type = KVM_SEV_SNP_PAGE_TYPE_ZERO; if (sev_snp->parent_obj.kernel_hashes) { @@ -1239,7 +1547,7 @@ snp_launch_update_kernel_hashes(SevSnpGuestState *sev_snp, uint32_t addr, sizeof(*sev_snp->kernel_hashes_data)); type = KVM_SEV_SNP_PAGE_TYPE_NORMAL; } - return snp_launch_update_data(addr, hva, len, type); + return snp_launch_update_data(addr, hva, len, type, errp); } static int @@ -1277,12 +1585,14 @@ snp_populate_metadata_pages(SevSnpGuestState *sev_snp, } if (type == KVM_SEV_SNP_PAGE_TYPE_CPUID) { - ret = snp_launch_update_cpuid(desc->base, hva, desc->len); + ret = snp_launch_update_cpuid(desc->base, hva, desc->len, + &error_fatal); } else if (desc->type == SEV_DESC_TYPE_SNP_KERNEL_HASHES) { ret = snp_launch_update_kernel_hashes(sev_snp, desc->base, hva, - desc->len); + desc->len, &error_fatal); } else { - ret = snp_launch_update_data(desc->base, hva, desc->len, type); + ret = snp_launch_update_data(desc->base, hva, desc->len, type, + &error_fatal); } if (ret) { @@ -1304,18 +1614,26 @@ sev_snp_launch_finish(SevCommonState *sev_common) struct kvm_sev_snp_launch_finish *finish = &sev_snp->kvm_finish_conf; /* - * To boot the SNP guest, the hypervisor is required to populate the CPUID - * and Secrets page before finalizing the launch flow. The location of - * the secrets and CPUID page is available through the OVMF metadata GUID. + * Populate all the metadata pages if not using an IGVM file. In the case + * where an IGVM file is provided it will be used to configure the metadata + * pages directly. */ - metadata = pc_system_get_ovmf_sev_metadata_ptr(); - if (metadata == NULL) { - error_report("%s: Failed to locate SEV metadata header", __func__); - exit(1); - } + if (!X86_MACHINE(qdev_get_machine())->igvm) { + /* + * To boot the SNP guest, the hypervisor is required to populate the + * CPUID and Secrets page before finalizing the launch flow. The + * location of the secrets and CPUID page is available through the + * OVMF metadata GUID. + */ + metadata = pc_system_get_ovmf_sev_metadata_ptr(); + if (metadata == NULL) { + error_report("%s: Failed to locate SEV metadata header", __func__); + exit(1); + } - /* Populate all the metadata pages */ - snp_populate_metadata_pages(sev_snp, metadata); + /* Populate all the metadata pages */ + snp_populate_metadata_pages(sev_snp, metadata); + } QTAILQ_FOREACH(data, &launch_update, next) { ret = sev_snp_launch_update(sev_snp, data); @@ -1425,6 +1743,39 @@ static int sev_snp_kvm_type(X86ConfidentialGuest *cg) return KVM_X86_SNP_VM; } +static int sev_init_supported_features(ConfidentialGuestSupport *cgs, + SevCommonState *sev_common, Error **errp) +{ + X86ConfidentialGuestClass *x86_klass = + X86_CONFIDENTIAL_GUEST_GET_CLASS(cgs); + /* + * Older kernels do not support query or setting of sev_features. In this + * case the set of supported features must be zero to match the settings + * in the kernel. + */ + if (x86_klass->kvm_type(X86_CONFIDENTIAL_GUEST(sev_common)) == + KVM_X86_DEFAULT_VM) { + sev_common->supported_sev_features = 0; + return 0; + } + + /* Query KVM for the supported set of sev_features */ + struct kvm_device_attr attr = { + .group = KVM_X86_GRP_SEV, + .attr = KVM_X86_SEV_VMSA_FEATURES, + .addr = (unsigned long)&sev_common->supported_sev_features, + }; + if (kvm_ioctl(kvm_state, KVM_GET_DEVICE_ATTR, &attr) < 0) { + error_setg(errp, "%s: failed to query supported sev_features", + __func__); + return -1; + } + if (sev_snp_enabled()) { + sev_common->supported_sev_features |= SVM_SEV_FEAT_SNP_ACTIVE; + } + return 0; +} + static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) { char *devname; @@ -1505,6 +1856,10 @@ static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) } } + if (sev_init_supported_features(cgs, sev_common, errp) < 0) { + return -1; + } + trace_kvm_sev_init(); switch (x86_klass->kvm_type(X86_CONFIDENTIAL_GUEST(sev_common))) { case KVM_X86_DEFAULT_VM: @@ -1516,6 +1871,40 @@ static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) case KVM_X86_SEV_ES_VM: case KVM_X86_SNP_VM: { struct kvm_sev_init args = { 0 }; + MachineState *machine = MACHINE(qdev_get_machine()); + X86MachineState *x86machine = X86_MACHINE(qdev_get_machine()); + + /* + * If configuration is provided via an IGVM file then the IGVM file + * might contain configuration of the initial vcpu context. For SEV + * the vcpu context includes the sev_features which should be applied + * to the vcpu. + * + * KVM does not synchronize sev_features from CPU state. Instead it + * requires sev_features to be provided as part of this initialization + * call which is subsequently automatically applied to the VMSA of + * each vcpu. + * + * The IGVM file is normally processed after initialization. Therefore + * we need to pre-process it here to extract sev_features in order to + * provide it to KVM_SEV_INIT2. Each cgs_* function that is called by + * the IGVM processor detects this pre-process by observing the state + * as SEV_STATE_UNINIT. + */ + if (x86machine->igvm) { + if (IGVM_CFG_GET_CLASS(x86machine->igvm) + ->process(x86machine->igvm, machine->cgs, true, errp) == + -1) { + return -1; + } + /* + * KVM maintains a bitmask of allowed sev_features. This does not + * include SVM_SEV_FEAT_SNP_ACTIVE which is set accordingly by KVM + * itself. Therefore we need to clear this flag. + */ + args.vmsa_features = sev_common->sev_features & + ~SVM_SEV_FEAT_SNP_ACTIVE; + } ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_INIT2, &args, &fw_error); break; @@ -1615,9 +2004,8 @@ sev_encrypt_flash(hwaddr gpa, uint8_t *ptr, uint64_t len, Error **errp) if (sev_check_state(sev_common, SEV_STATE_LAUNCH_UPDATE)) { int ret; - ret = klass->launch_update_data(sev_common, gpa, ptr, len); + ret = klass->launch_update_data(sev_common, gpa, ptr, len, errp); if (ret < 0) { - error_setg(errp, "SEV: Failed to encrypt pflash rom"); return ret; } } @@ -1782,40 +2170,109 @@ sev_es_find_reset_vector(void *flash_ptr, uint64_t flash_size, return sev_es_parse_reset_block(info, addr); } -void sev_es_set_reset_vector(CPUState *cpu) + +static void seg_to_vmsa(const SegmentCache *cpu_seg, struct vmcb_seg *vmsa_seg) { - X86CPU *x86; - CPUX86State *env; - ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; - SevCommonState *sev_common = SEV_COMMON( - object_dynamic_cast(OBJECT(cgs), TYPE_SEV_COMMON)); + vmsa_seg->selector = cpu_seg->selector; + vmsa_seg->base = cpu_seg->base; + vmsa_seg->limit = cpu_seg->limit; + vmsa_seg->attrib = FLAGS_SEGCACHE_TO_VMSA(cpu_seg->flags); +} - /* Only update if we have valid reset information */ - if (!sev_common || !sev_common->reset_data_valid) { - return; - } +static void initialize_vmsa(const CPUState *cpu, struct sev_es_save_area *vmsa) +{ + const X86CPU *x86 = X86_CPU(cpu); + const CPUX86State *env = &x86->env; - /* Do not update the BSP reset state */ - if (cpu->cpu_index == 0) { - return; + /* + * Initialize the SEV-ES save area from the current state of + * the CPU. The entire state does not need to be copied, only the state + * that is copied back to the CPUState in sev_apply_cpu_context. + */ + memset(vmsa, 0, sizeof(struct sev_es_save_area)); + vmsa->efer = env->efer; + vmsa->cr0 = env->cr[0]; + vmsa->cr3 = env->cr[3]; + vmsa->cr4 = env->cr[4]; + vmsa->xcr0 = env->xcr0; + vmsa->g_pat = env->pat; + + seg_to_vmsa(&env->segs[R_CS], &vmsa->cs); + seg_to_vmsa(&env->segs[R_DS], &vmsa->ds); + seg_to_vmsa(&env->segs[R_ES], &vmsa->es); + seg_to_vmsa(&env->segs[R_FS], &vmsa->fs); + seg_to_vmsa(&env->segs[R_GS], &vmsa->gs); + seg_to_vmsa(&env->segs[R_SS], &vmsa->ss); + + seg_to_vmsa(&env->gdt, &vmsa->gdtr); + seg_to_vmsa(&env->idt, &vmsa->idtr); + seg_to_vmsa(&env->ldt, &vmsa->ldtr); + seg_to_vmsa(&env->tr, &vmsa->tr); + + vmsa->dr6 = env->dr[6]; + vmsa->dr7 = env->dr[7]; + + vmsa->rax = env->regs[R_EAX]; + vmsa->rcx = env->regs[R_ECX]; + vmsa->rdx = env->regs[R_EDX]; + vmsa->rbx = env->regs[R_EBX]; + vmsa->rsp = env->regs[R_ESP]; + vmsa->rbp = env->regs[R_EBP]; + vmsa->rsi = env->regs[R_ESI]; + vmsa->rdi = env->regs[R_EDI]; + +#ifdef TARGET_X86_64 + vmsa->r8 = env->regs[R_R8]; + vmsa->r9 = env->regs[R_R9]; + vmsa->r10 = env->regs[R_R10]; + vmsa->r11 = env->regs[R_R11]; + vmsa->r12 = env->regs[R_R12]; + vmsa->r13 = env->regs[R_R13]; + vmsa->r14 = env->regs[R_R14]; + vmsa->r15 = env->regs[R_R15]; +#endif + + vmsa->rip = env->eip; + vmsa->rflags = env->eflags; +} + +static void sev_es_set_ap_context(uint32_t reset_addr) +{ + CPUState *cpu; + struct sev_es_save_area vmsa; + SegmentCache cs; + + cs.selector = 0xf000; + cs.base = reset_addr & 0xffff0000; + cs.limit = 0xffff; + cs.flags = DESC_P_MASK | DESC_S_MASK | DESC_CS_MASK | DESC_R_MASK | + DESC_A_MASK; + + CPU_FOREACH(cpu) { + if (cpu->cpu_index == 0) { + /* Do not update the BSP reset state */ + continue; + } + initialize_vmsa(cpu, &vmsa); + seg_to_vmsa(&cs, &vmsa.cs); + vmsa.rip = reset_addr & 0x0000ffff; + sev_set_cpu_context(cpu->cpu_index, &vmsa, + sizeof(struct sev_es_save_area), + 0, &error_fatal); } +} - x86 = X86_CPU(cpu); - env = &x86->env; - - cpu_x86_load_seg_cache(env, R_CS, 0xf000, sev_common->reset_cs, 0xffff, - DESC_P_MASK | DESC_S_MASK | DESC_CS_MASK | - DESC_R_MASK | DESC_A_MASK); - - env->eip = sev_common->reset_ip; +void sev_es_set_reset_vector(CPUState *cpu) +{ + if (sev_enabled()) { + sev_apply_cpu_context(cpu); + } } int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size) { - CPUState *cpu; uint32_t addr; int ret; - SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); if (!sev_es_enabled()) { return 0; @@ -1828,14 +2285,12 @@ int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size) return ret; } + /* + * The reset vector is saved into a CPU context for each AP but not for + * the BSP. This is applied during guest startup or when the CPU is reset. + */ if (addr) { - sev_common->reset_cs = addr & 0xffff0000; - sev_common->reset_ip = addr & 0x0000ffff; - sev_common->reset_data_valid = true; - - CPU_FOREACH(cpu) { - sev_es_set_reset_vector(cpu); - } + sev_es_set_ap_context(addr); } return 0; @@ -2037,6 +2492,237 @@ static void sev_common_set_kernel_hashes(Object *obj, bool value, Error **errp) SEV_COMMON(obj)->kernel_hashes = value; } +static bool cgs_check_support(ConfidentialGuestPlatformType platform, + uint16_t platform_version, uint8_t highest_vtl, + uint64_t shared_gpa_boundary) +{ + return (((platform == CGS_PLATFORM_SEV_SNP) && sev_snp_enabled()) || + ((platform == CGS_PLATFORM_SEV_ES) && sev_es_enabled()) || + ((platform == CGS_PLATFORM_SEV) && sev_enabled())); +} + +static int cgs_set_guest_state(hwaddr gpa, uint8_t *ptr, uint64_t len, + ConfidentialGuestPageType memory_type, + uint16_t cpu_index, Error **errp) +{ + SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); + SevCommonStateClass *klass = SEV_COMMON_GET_CLASS(sev_common); + + if (sev_common->state == SEV_STATE_UNINIT) { + /* Pre-processing of IGVM file called from sev_common_kvm_init() */ + if ((cpu_index == 0) && (memory_type == CGS_PAGE_TYPE_VMSA)) { + const struct sev_es_save_area *sa = + (const struct sev_es_save_area *)ptr; + if (len < sizeof(*sa)) { + error_setg(errp, "%s: invalid VMSA length encountered", + __func__); + return -1; + } + if (check_sev_features(sev_common, sa->sev_features, errp) < 0) { + return -1; + } + sev_common->sev_features = sa->sev_features; + } + return 0; + } + + if (!sev_enabled()) { + error_setg(errp, "%s: attempt to configure guest memory, but SEV " + "is not enabled", __func__); + return -1; + } + + switch (memory_type) { + case CGS_PAGE_TYPE_NORMAL: + case CGS_PAGE_TYPE_ZERO: + return klass->launch_update_data(sev_common, gpa, ptr, len, errp); + + case CGS_PAGE_TYPE_VMSA: + if (!sev_es_enabled()) { + error_setg(errp, + "%s: attempt to configure initial VMSA, but SEV-ES " + "is not supported", + __func__); + return -1; + } + if (check_vmsa_supported(sev_common, gpa, + (const struct sev_es_save_area *)ptr, + errp) < 0) { + return -1; + } + return sev_set_cpu_context(cpu_index, ptr, len, gpa, errp); + + case CGS_PAGE_TYPE_UNMEASURED: + if (sev_snp_enabled()) { + return snp_launch_update_data( + gpa, ptr, len, KVM_SEV_SNP_PAGE_TYPE_UNMEASURED, errp); + } + /* No action required if not SEV-SNP */ + return 0; + + case CGS_PAGE_TYPE_SECRETS: + if (!sev_snp_enabled()) { + error_setg(errp, + "%s: attempt to configure secrets page, but SEV-SNP " + "is not supported", + __func__); + return -1; + } + return snp_launch_update_data(gpa, ptr, len, + KVM_SEV_SNP_PAGE_TYPE_SECRETS, errp); + + case CGS_PAGE_TYPE_REQUIRED_MEMORY: + if (kvm_convert_memory(gpa, len, true) < 0) { + error_setg( + errp, + "%s: failed to configure required memory. gpa: %lX, type: %d", + __func__, gpa, memory_type); + return -1; + } + return 0; + + case CGS_PAGE_TYPE_CPUID: + if (!sev_snp_enabled()) { + error_setg(errp, + "%s: attempt to configure CPUID page, but SEV-SNP " + "is not supported", + __func__); + return -1; + } + return snp_launch_update_cpuid(gpa, ptr, len, errp); + } + error_setg(errp, "%s: failed to update guest. gpa: %lX, type: %d", __func__, + gpa, memory_type); + return -1; +} + +static int cgs_get_mem_map_entry(int index, + ConfidentialGuestMemoryMapEntry *entry, + Error **errp) +{ + struct e820_entry *table; + int num_entries; + + SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); + if (sev_common->state == SEV_STATE_UNINIT) { + /* Pre-processing of IGVM file called from sev_common_kvm_init() */ + return 1; + } + + num_entries = e820_get_table(&table); + if ((index < 0) || (index >= num_entries)) { + return 1; + } + entry->gpa = table[index].address; + entry->size = table[index].length; + switch (table[index].type) { + case E820_RAM: + entry->type = CGS_MEM_RAM; + break; + case E820_RESERVED: + entry->type = CGS_MEM_RESERVED; + break; + case E820_ACPI: + entry->type = CGS_MEM_ACPI; + break; + case E820_NVS: + entry->type = CGS_MEM_NVS; + break; + case E820_UNUSABLE: + entry->type = CGS_MEM_UNUSABLE; + break; + } + return 0; +} + +static int cgs_set_guest_policy(ConfidentialGuestPolicyType policy_type, + uint64_t policy, void *policy_data1, + uint32_t policy_data1_size, void *policy_data2, + uint32_t policy_data2_size, Error **errp) +{ + SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); + if (sev_common->state == SEV_STATE_UNINIT) { + /* Pre-processing of IGVM file called from sev_common_kvm_init() */ + return 0; + } + + if (policy_type != GUEST_POLICY_SEV) { + error_setg(errp, "%s: Invalid guest policy type provided for SEV: %d", + __func__, policy_type); + return -1; + } + /* + * SEV-SNP handles policy differently. The policy flags are defined in + * kvm_start_conf.policy and an ID block and ID auth can be provided. + */ + if (sev_snp_enabled()) { + SevSnpGuestState *sev_snp_guest = + SEV_SNP_GUEST(MACHINE(qdev_get_machine())->cgs); + struct kvm_sev_snp_launch_finish *finish = + &sev_snp_guest->kvm_finish_conf; + + /* + * The policy consists of flags in 'policy' and optionally an ID block + * and ID auth in policy_data1 and policy_data2 respectively. The ID + * block and auth are optional so clear any previous ID block and auth + * and set them if provided, but always set the policy flags. + */ + g_free(sev_snp_guest->id_block); + g_free((guchar *)finish->id_block_uaddr); + g_free(sev_snp_guest->id_auth); + g_free((guchar *)finish->id_auth_uaddr); + sev_snp_guest->id_block = NULL; + finish->id_block_uaddr = 0; + sev_snp_guest->id_auth = NULL; + finish->id_auth_uaddr = 0; + + if (policy_data1_size > 0) { + struct sev_snp_id_authentication *id_auth = + (struct sev_snp_id_authentication *)policy_data2; + + if (policy_data1_size != KVM_SEV_SNP_ID_BLOCK_SIZE) { + error_setg(errp, "%s: Invalid SEV-SNP ID block: incorrect size", + __func__); + return -1; + } + if (policy_data2_size != KVM_SEV_SNP_ID_AUTH_SIZE) { + error_setg(errp, + "%s: Invalid SEV-SNP ID auth block: incorrect size", + __func__); + return -1; + } + assert(policy_data1 != NULL); + assert(policy_data2 != NULL); + + finish->id_block_uaddr = + (__u64)g_memdup2(policy_data1, KVM_SEV_SNP_ID_BLOCK_SIZE); + finish->id_auth_uaddr = + (__u64)g_memdup2(policy_data2, KVM_SEV_SNP_ID_AUTH_SIZE); + + /* + * Check if an author key has been provided and use that to flag + * whether the author key is enabled. The first of the author key + * must be non-zero to indicate the key type, which will currently + * always be 2. + */ + sev_snp_guest->kvm_finish_conf.auth_key_en = + id_auth->author_key[0] ? 1 : 0; + finish->id_block_en = 1; + } + sev_snp_guest->kvm_start_conf.policy = policy; + } else { + SevGuestState *sev_guest = SEV_GUEST(MACHINE(qdev_get_machine())->cgs); + /* Only the policy flags are supported for SEV and SEV-ES */ + if ((policy_data1_size > 0) || (policy_data2_size > 0) || !sev_guest) { + error_setg(errp, "%s: An ID block/ID auth block has been provided " + "but SEV-SNP is not enabled", __func__); + return -1; + } + sev_guest->policy = policy; + } + return 0; +} + static void sev_common_class_init(ObjectClass *oc, const void *data) { @@ -2060,6 +2746,8 @@ static void sev_common_instance_init(Object *obj) { SevCommonState *sev_common = SEV_COMMON(obj); + ConfidentialGuestSupportClass *cgs = + CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(obj); sev_common->kvm_type = -1; @@ -2070,6 +2758,12 @@ sev_common_instance_init(Object *obj) object_property_add_uint32_ptr(obj, "reduced-phys-bits", &sev_common->reduced_phys_bits, OBJ_PROP_FLAG_READWRITE); + cgs->check_support = cgs_check_support; + cgs->set_guest_state = cgs_set_guest_state; + cgs->get_mem_map_entry = cgs_get_mem_map_entry; + cgs->set_guest_policy = cgs_set_guest_policy; + + QTAILQ_INIT(&sev_common->launch_vmsa); } /* sev guest info common to sev/sev-es/sev-snp */ |