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Diffstat (limited to 'target-i386/kvm.c')
-rw-r--r--target-i386/kvm.c153
1 files changed, 91 insertions, 62 deletions
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 9ccbcb5be5..73e2035637 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -98,6 +98,19 @@ static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max)
return cpuid;
}
+/* Run KVM_GET_SUPPORTED_CPUID ioctl(), allocating a buffer large enough
+ * for all entries.
+ */
+static struct kvm_cpuid2 *get_supported_cpuid(KVMState *s)
+{
+ struct kvm_cpuid2 *cpuid;
+ int max = 1;
+ while ((cpuid = try_get_cpuid(s, max)) == NULL) {
+ max *= 2;
+ }
+ return cpuid;
+}
+
struct kvm_para_features {
int cap;
int feature;
@@ -123,60 +136,98 @@ static int get_para_features(KVMState *s)
}
+/* Returns the value for a specific register on the cpuid entry
+ */
+static uint32_t cpuid_entry_get_reg(struct kvm_cpuid_entry2 *entry, int reg)
+{
+ uint32_t ret = 0;
+ switch (reg) {
+ case R_EAX:
+ ret = entry->eax;
+ break;
+ case R_EBX:
+ ret = entry->ebx;
+ break;
+ case R_ECX:
+ ret = entry->ecx;
+ break;
+ case R_EDX:
+ ret = entry->edx;
+ break;
+ }
+ return ret;
+}
+
+/* Find matching entry for function/index on kvm_cpuid2 struct
+ */
+static struct kvm_cpuid_entry2 *cpuid_find_entry(struct kvm_cpuid2 *cpuid,
+ uint32_t function,
+ uint32_t index)
+{
+ int i;
+ for (i = 0; i < cpuid->nent; ++i) {
+ if (cpuid->entries[i].function == function &&
+ cpuid->entries[i].index == index) {
+ return &cpuid->entries[i];
+ }
+ }
+ /* not found: */
+ return NULL;
+}
+
uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
uint32_t index, int reg)
{
struct kvm_cpuid2 *cpuid;
- int i, max;
uint32_t ret = 0;
uint32_t cpuid_1_edx;
- int has_kvm_features = 0;
+ bool found = false;
- max = 1;
- while ((cpuid = try_get_cpuid(s, max)) == NULL) {
- max *= 2;
+ cpuid = get_supported_cpuid(s);
+
+ struct kvm_cpuid_entry2 *entry = cpuid_find_entry(cpuid, function, index);
+ if (entry) {
+ found = true;
+ ret = cpuid_entry_get_reg(entry, reg);
}
- for (i = 0; i < cpuid->nent; ++i) {
- if (cpuid->entries[i].function == function &&
- cpuid->entries[i].index == index) {
- if (cpuid->entries[i].function == KVM_CPUID_FEATURES) {
- has_kvm_features = 1;
- }
- switch (reg) {
- case R_EAX:
- ret = cpuid->entries[i].eax;
- break;
- case R_EBX:
- ret = cpuid->entries[i].ebx;
- break;
- case R_ECX:
- ret = cpuid->entries[i].ecx;
- break;
- case R_EDX:
- ret = cpuid->entries[i].edx;
- switch (function) {
- case 1:
- /* KVM before 2.6.30 misreports the following features */
- ret |= CPUID_MTRR | CPUID_PAT | CPUID_MCE | CPUID_MCA;
- break;
- case 0x80000001:
- /* On Intel, kvm returns cpuid according to the Intel spec,
- * so add missing bits according to the AMD spec:
- */
- cpuid_1_edx = kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
- ret |= cpuid_1_edx & CPUID_EXT2_AMD_ALIASES;
- break;
- }
- break;
- }
+ /* Fixups for the data returned by KVM, below */
+
+ if (function == 1 && reg == R_EDX) {
+ /* KVM before 2.6.30 misreports the following features */
+ ret |= CPUID_MTRR | CPUID_PAT | CPUID_MCE | CPUID_MCA;
+ } else if (function == 1 && reg == R_ECX) {
+ /* We can set the hypervisor flag, even if KVM does not return it on
+ * GET_SUPPORTED_CPUID
+ */
+ ret |= CPUID_EXT_HYPERVISOR;
+ /* tsc-deadline flag is not returned by GET_SUPPORTED_CPUID, but it
+ * can be enabled if the kernel has KVM_CAP_TSC_DEADLINE_TIMER,
+ * and the irqchip is in the kernel.
+ */
+ if (kvm_irqchip_in_kernel() &&
+ kvm_check_extension(s, KVM_CAP_TSC_DEADLINE_TIMER)) {
+ ret |= CPUID_EXT_TSC_DEADLINE_TIMER;
+ }
+
+ /* x2apic is reported by GET_SUPPORTED_CPUID, but it can't be enabled
+ * without the in-kernel irqchip
+ */
+ if (!kvm_irqchip_in_kernel()) {
+ ret &= ~CPUID_EXT_X2APIC;
}
+ } else if (function == 0x80000001 && reg == R_EDX) {
+ /* On Intel, kvm returns cpuid according to the Intel spec,
+ * so add missing bits according to the AMD spec:
+ */
+ cpuid_1_edx = kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
+ ret |= cpuid_1_edx & CPUID_EXT2_AMD_ALIASES;
}
g_free(cpuid);
/* fallback for older kernels */
- if (!has_kvm_features && (function == KVM_CPUID_FEATURES)) {
+ if ((function == KVM_CPUID_FEATURES) && !found) {
ret = get_para_features(s);
}
@@ -361,31 +412,12 @@ int kvm_arch_init_vcpu(CPUX86State *env)
struct kvm_cpuid2 cpuid;
struct kvm_cpuid_entry2 entries[100];
} QEMU_PACKED cpuid_data;
- KVMState *s = env->kvm_state;
uint32_t limit, i, j, cpuid_i;
uint32_t unused;
struct kvm_cpuid_entry2 *c;
uint32_t signature[3];
int r;
- env->cpuid_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_EDX);
-
- i = env->cpuid_ext_features & CPUID_EXT_HYPERVISOR;
- j = env->cpuid_ext_features & CPUID_EXT_TSC_DEADLINE_TIMER;
- env->cpuid_ext_features &= kvm_arch_get_supported_cpuid(s, 1, 0, R_ECX);
- env->cpuid_ext_features |= i;
- if (j && kvm_irqchip_in_kernel() &&
- kvm_check_extension(s, KVM_CAP_TSC_DEADLINE_TIMER)) {
- env->cpuid_ext_features |= CPUID_EXT_TSC_DEADLINE_TIMER;
- }
-
- env->cpuid_ext2_features &= kvm_arch_get_supported_cpuid(s, 0x80000001,
- 0, R_EDX);
- env->cpuid_ext3_features &= kvm_arch_get_supported_cpuid(s, 0x80000001,
- 0, R_ECX);
- env->cpuid_svm_features &= kvm_arch_get_supported_cpuid(s, 0x8000000A,
- 0, R_EDX);
-
cpuid_i = 0;
/* Paravirtualization CPUIDs */
@@ -406,8 +438,7 @@ int kvm_arch_init_vcpu(CPUX86State *env)
c = &cpuid_data.entries[cpuid_i++];
memset(c, 0, sizeof(*c));
c->function = KVM_CPUID_FEATURES;
- c->eax = env->cpuid_kvm_features &
- kvm_arch_get_supported_cpuid(s, KVM_CPUID_FEATURES, 0, R_EAX);
+ c->eax = env->cpuid_kvm_features;
if (hyperv_enabled()) {
memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
@@ -528,8 +559,6 @@ int kvm_arch_init_vcpu(CPUX86State *env)
/* Call Centaur's CPUID instructions they are supported. */
if (env->cpuid_xlevel2 > 0) {
- env->cpuid_ext4_features &=
- kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX);
cpu_x86_cpuid(env, 0xC0000000, 0, &limit, &unused, &unused, &unused);
for (i = 0xC0000000; i <= limit; i++) {