diff options
| -rw-r--r-- | docs/hyperv.txt | 10 | ||||
| -rw-r--r-- | target/i386/cpu.c | 1 | ||||
| -rw-r--r-- | target/i386/cpu.h | 1 | ||||
| -rw-r--r-- | target/i386/kvm.c | 89 |
4 files changed, 87 insertions, 14 deletions
diff --git a/docs/hyperv.txt b/docs/hyperv.txt index c423e0f..beadb2d 100644 --- a/docs/hyperv.txt +++ b/docs/hyperv.txt @@ -175,6 +175,16 @@ without the feature to find out if enabling it is beneficial. Requires: hv-vapic +4. Development features +======================== +In some cases (e.g. during development) it may make sense to use QEMU in +'pass-through' mode and give Windows guests all enlightenments currently +supported by KVM. This pass-through mode is enabled by "hv-passthrough" CPU +flag. +Note: enabling this flag effectively prevents migration as supported features +may differ between target and destination. + + 4. Useful links ================ Hyper-V Top Level Functional specification and other information: diff --git a/target/i386/cpu.c b/target/i386/cpu.c index e90c1ac..e07996c 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -5883,6 +5883,7 @@ static Property x86_cpu_properties[] = { HYPERV_FEAT_EVMCS, 0), DEFINE_PROP_BIT64("hv-ipi", X86CPU, hyperv_features, HYPERV_FEAT_IPI, 0), + DEFINE_PROP_BOOL("hv-passthrough", X86CPU, hyperv_passthrough, false), DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true), DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false), diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 30cd1a0..86edbf5 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1390,6 +1390,7 @@ struct X86CPU { char *hyperv_vendor_id; bool hyperv_synic_kvm_only; uint64_t hyperv_features; + bool hyperv_passthrough; bool check_cpuid; bool enforce_cpuid; diff --git a/target/i386/kvm.c b/target/i386/kvm.c index a041b4d..93ac6ba 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -639,7 +639,7 @@ static bool hyperv_enabled(X86CPU *cpu) CPUState *cs = CPU(cpu); return kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV) > 0 && ((cpu->hyperv_spinlock_attempts != HYPERV_SPINLOCK_NEVER_RETRY) || - cpu->hyperv_features); + cpu->hyperv_features || cpu->hyperv_passthrough); } static int kvm_arch_set_tsc_khz(CPUState *cs) @@ -985,10 +985,10 @@ static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid, { X86CPU *cpu = X86_CPU(cs); CPUX86State *env = &cpu->env; - uint32_t r, fw, bits;; + uint32_t r, fw, bits; int i; - if (!hyperv_feat_enabled(cpu, feature)) { + if (!hyperv_feat_enabled(cpu, feature) && !cpu->hyperv_passthrough) { return 0; } @@ -1001,15 +1001,23 @@ static int hv_cpuid_check_and_set(CPUState *cs, struct kvm_cpuid2 *cpuid, } if (hv_cpuid_get_fw(cpuid, fw, &r) || (r & bits) != bits) { - fprintf(stderr, - "Hyper-V %s is not supported by kernel\n", - kvm_hyperv_properties[feature].desc); - return 1; + if (hyperv_feat_enabled(cpu, feature)) { + fprintf(stderr, + "Hyper-V %s is not supported by kernel\n", + kvm_hyperv_properties[feature].desc); + return 1; + } else { + return 0; + } } env->features[fw] |= bits; } + if (cpu->hyperv_passthrough) { + cpu->hyperv_features |= BIT(feature); + } + return 0; } @@ -1027,22 +1035,29 @@ static int hyperv_handle_properties(CPUState *cs, struct kvm_cpuid_entry2 *c; uint32_t signature[3]; uint32_t cpuid_i = 0; - int r = 0; + int r; if (!hyperv_enabled(cpu)) return 0; - if (hyperv_feat_enabled(cpu, HYPERV_FEAT_EVMCS)) { + if (hyperv_feat_enabled(cpu, HYPERV_FEAT_EVMCS) || + cpu->hyperv_passthrough) { uint16_t evmcs_version; - if (kvm_vcpu_enable_cap(cs, KVM_CAP_HYPERV_ENLIGHTENED_VMCS, 0, - (uintptr_t)&evmcs_version)) { + r = kvm_vcpu_enable_cap(cs, KVM_CAP_HYPERV_ENLIGHTENED_VMCS, 0, + (uintptr_t)&evmcs_version); + + if (hyperv_feat_enabled(cpu, HYPERV_FEAT_EVMCS) && r) { fprintf(stderr, "Hyper-V %s is not supported by kernel\n", kvm_hyperv_properties[HYPERV_FEAT_EVMCS].desc); return -ENOSYS; } - env->features[FEAT_HV_RECOMM_EAX] |= HV_ENLIGHTENED_VMCS_RECOMMENDED; - env->features[FEAT_HV_NESTED_EAX] = evmcs_version; + + if (!r) { + env->features[FEAT_HV_RECOMM_EAX] |= + HV_ENLIGHTENED_VMCS_RECOMMENDED; + env->features[FEAT_HV_NESTED_EAX] = evmcs_version; + } } if (kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_CPUID) > 0) { @@ -1051,8 +1066,33 @@ static int hyperv_handle_properties(CPUState *cs, cpuid = get_supported_hv_cpuid_legacy(cs); } + if (cpu->hyperv_passthrough) { + memcpy(cpuid_ent, &cpuid->entries[0], + cpuid->nent * sizeof(cpuid->entries[0])); + + c = cpuid_find_entry(cpuid, HV_CPUID_FEATURES, 0); + if (c) { + env->features[FEAT_HYPERV_EAX] = c->eax; + env->features[FEAT_HYPERV_EBX] = c->ebx; + env->features[FEAT_HYPERV_EDX] = c->eax; + } + c = cpuid_find_entry(cpuid, HV_CPUID_ENLIGHTMENT_INFO, 0); + if (c) { + env->features[FEAT_HV_RECOMM_EAX] = c->eax; + + /* hv-spinlocks may have been overriden */ + if (cpu->hyperv_spinlock_attempts != HYPERV_SPINLOCK_NEVER_RETRY) { + c->ebx = cpu->hyperv_spinlock_attempts; + } + } + c = cpuid_find_entry(cpuid, HV_CPUID_NESTED_FEATURES, 0); + if (c) { + env->features[FEAT_HV_NESTED_EAX] = c->eax; + } + } + /* Features */ - r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_RELAXED); + r = hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_RELAXED); r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_VAPIC); r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_TIME); r |= hv_cpuid_check_and_set(cs, cpuid, HYPERV_FEAT_CRASH); @@ -1085,6 +1125,12 @@ static int hyperv_handle_properties(CPUState *cs, goto free; } + if (cpu->hyperv_passthrough) { + /* We already copied all feature words from KVM as is */ + r = cpuid->nent; + goto free; + } + c = &cpuid_ent[cpuid_i++]; c->function = HV_CPUID_VENDOR_AND_MAX_FUNCTIONS; if (!cpu->hyperv_vendor_id) { @@ -1156,11 +1202,26 @@ free: return r; } +static Error *hv_passthrough_mig_blocker; + static int hyperv_init_vcpu(X86CPU *cpu) { CPUState *cs = CPU(cpu); + Error *local_err = NULL; int ret; + if (cpu->hyperv_passthrough && hv_passthrough_mig_blocker == NULL) { + error_setg(&hv_passthrough_mig_blocker, + "'hv-passthrough' CPU flag prevents migration, use explicit" + " set of hv-* flags instead"); + ret = migrate_add_blocker(hv_passthrough_mig_blocker, &local_err); + if (local_err) { + error_report_err(local_err); + error_free(hv_passthrough_mig_blocker); + return ret; + } + } + if (hyperv_feat_enabled(cpu, HYPERV_FEAT_VPINDEX) && !hv_vpindex_settable) { /* * the kernel doesn't support setting vp_index; assert that its value |