[v3,24/70] i386/kvm: Move architectural CPUID leaf generation to separate helper

Commit Message

Xiaoyao Li Nov. 15, 2023, 7:14 a.m. UTC

From: Sean Christopherson <[e-mail]>

Move the architectural (for lack of a better term) CPUID leaf generation
to a separate helper so that the generation code can be reused by TDX,
which needs to generate a canonical VM-scoped configuration.

Signed-off-by: Sean Christopherson <[e-mail]>
Signed-off-by: Xiaoyao Li <[e-mail]>
---
 target/i386/kvm/kvm.c      | 454 +++++++++++++++++++------------------
 target/i386/kvm/kvm_i386.h |   3 +
 2 files changed, 235 insertions(+), 222 deletions(-)

Patch

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index f2627dd61d2b..dafe4d262977 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -1733,6 +1733,236 @@  static void kvm_init_nested_state(CPUX86State *env)
     }
 }
 
+uint32_t kvm_x86_arch_cpuid(CPUX86State *env, struct kvm_cpuid_entry2 *entries,
+                            uint32_t cpuid_i)
+{
+    uint32_t limit, i, j;
+    uint32_t unused;
+    struct kvm_cpuid_entry2 *c;
+
+    cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);
+
+    for (i = 0; i <= limit; i++) {
+        if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+            fprintf(stderr, "unsupported level value: 0x%x\n", limit);
+            abort();
+        }
+        c = &entries[cpuid_i++];
+
+        switch (i) {
+        case 2: {
+            /* Keep reading function 2 till all the input is received */
+            int times;
+
+            c->function = i;
+            c->flags = KVM_CPUID_FLAG_STATEFUL_FUNC |
+                       KVM_CPUID_FLAG_STATE_READ_NEXT;
+            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            times = c->eax & 0xff;
+
+            for (j = 1; j < times; ++j) {
+                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                    fprintf(stderr, "cpuid_data is full, no space for "
+                            "cpuid(eax:2):eax & 0xf = 0x%x\n", times);
+                    abort();
+                }
+                c = &entries[cpuid_i++];
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_STATEFUL_FUNC;
+                cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            }
+            break;
+        }
+        case 0x1f:
+            if (env->nr_dies < 2) {
+                cpuid_i--;
+                break;
+            }
+            /* fallthrough */
+        case 4:
+        case 0xb:
+        case 0xd:
+            for (j = 0; ; j++) {
+                if (i == 0xd && j == 64) {
+                    break;
+                }
+
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                c->index = j;
+                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
+
+                if (i == 4 && c->eax == 0) {
+                    break;
+                }
+                if (i == 0xb && !(c->ecx & 0xff00)) {
+                    break;
+                }
+                if (i == 0x1f && !(c->ecx & 0xff00)) {
+                    break;
+                }
+                if (i == 0xd && c->eax == 0) {
+                    continue;
+                }
+                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                    fprintf(stderr, "cpuid_data is full, no space for "
+                            "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
+                    abort();
+                }
+                c = &entries[cpuid_i++];
+            }
+            break;
+        case 0x7:
+        case 0x12:
+            for (j = 0; ; j++) {
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                c->index = j;
+                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
+
+                if (j > 1 && (c->eax & 0xf) != 1) {
+                    break;
+                }
+
+                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                    fprintf(stderr, "cpuid_data is full, no space for "
+                                "cpuid(eax:0x12,ecx:0x%x)\n", j);
+                    abort();
+                }
+                c = &entries[cpuid_i++];
+            }
+            break;
+        case 0x14:
+        case 0x1d:
+        case 0x1e: {
+            uint32_t times;
+
+            c->function = i;
+            c->index = 0;
+            c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            times = c->eax;
+
+            for (j = 1; j <= times; ++j) {
+                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                    fprintf(stderr, "cpuid_data is full, no space for "
+                                "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
+                    abort();
+                }
+                c = &entries[cpuid_i++];
+                c->function = i;
+                c->index = j;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            }
+            break;
+        }
+        default:
+            c->function = i;
+            c->flags = 0;
+            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            if (!c->eax && !c->ebx && !c->ecx && !c->edx) {
+                /*
+                 * KVM already returns all zeroes if a CPUID entry is missing,
+                 * so we can omit it and avoid hitting KVM's 80-entry limit.
+                 */
+                cpuid_i--;
+            }
+            break;
+        }
+    }
+
+    if (limit >= 0x0a) {
+        uint32_t eax, edx;
+
+        cpu_x86_cpuid(env, 0x0a, 0, &eax, &unused, &unused, &edx);
+
+        has_architectural_pmu_version = eax & 0xff;
+        if (has_architectural_pmu_version > 0) {
+            num_architectural_pmu_gp_counters = (eax & 0xff00) >> 8;
+
+            /* Shouldn't be more than 32, since that's the number of bits
+             * available in EBX to tell us _which_ counters are available.
+             * Play it safe.
+             */
+            if (num_architectural_pmu_gp_counters > MAX_GP_COUNTERS) {
+                num_architectural_pmu_gp_counters = MAX_GP_COUNTERS;
+            }
+
+            if (has_architectural_pmu_version > 1) {
+                num_architectural_pmu_fixed_counters = edx & 0x1f;
+
+                if (num_architectural_pmu_fixed_counters > MAX_FIXED_COUNTERS) {
+                    num_architectural_pmu_fixed_counters = MAX_FIXED_COUNTERS;
+                }
+            }
+        }
+    }
+
+    cpu_x86_cpuid(env, 0x80000000, 0, &limit, &unused, &unused, &unused);
+
+    for (i = 0x80000000; i <= limit; i++) {
+        if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+            fprintf(stderr, "unsupported xlevel value: 0x%x\n", limit);
+            abort();
+        }
+        c = &entries[cpuid_i++];
+
+        switch (i) {
+        case 0x8000001d:
+            /* Query for all AMD cache information leaves */
+            for (j = 0; ; j++) {
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                c->index = j;
+                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
+
+                if (c->eax == 0) {
+                    break;
+                }
+                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                    fprintf(stderr, "cpuid_data is full, no space for "
+                            "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
+                    abort();
+                }
+                c = &entries[cpuid_i++];
+            }
+            break;
+        default:
+            c->function = i;
+            c->flags = 0;
+            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+            if (!c->eax && !c->ebx && !c->ecx && !c->edx) {
+                /*
+                 * KVM already returns all zeroes if a CPUID entry is missing,
+                 * so we can omit it and avoid hitting KVM's 80-entry limit.
+                 */
+                cpuid_i--;
+            }
+            break;
+        }
+    }
+
+    /* Call Centaur's CPUID instructions they are supported. */
+    if (env->cpuid_xlevel2 > 0) {
+        cpu_x86_cpuid(env, 0xC0000000, 0, &limit, &unused, &unused, &unused);
+
+        for (i = 0xC0000000; i <= limit; i++) {
+            if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
+                fprintf(stderr, "unsupported xlevel2 value: 0x%x\n", limit);
+                abort();
+            }
+            c = &entries[cpuid_i++];
+
+            c->function = i;
+            c->flags = 0;
+            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
+        }
+    }
+
+    return cpuid_i;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     struct {
@@ -1749,8 +1979,7 @@  int kvm_arch_init_vcpu(CPUState *cs)
 
     X86CPU *cpu = X86_CPU(cs);
     CPUX86State *env = &cpu->env;
-    uint32_t limit, i, j, cpuid_i;
-    uint32_t unused;
+    uint32_t cpuid_i;
     struct kvm_cpuid_entry2 *c;
     uint32_t signature[3];
     int kvm_base = KVM_CPUID_SIGNATURE;
@@ -1903,8 +2132,6 @@  int kvm_arch_init_vcpu(CPUState *cs)
         c->edx = env->features[FEAT_KVM_HINTS];
     }
 
-    cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);
-
     if (cpu->kvm_pv_enforce_cpuid) {
         r = kvm_vcpu_enable_cap(cs, KVM_CAP_ENFORCE_PV_FEATURE_CPUID, 0, 1);
         if (r < 0) {
@@ -1915,224 +2142,7 @@  int kvm_arch_init_vcpu(CPUState *cs)
         }
     }
 
-    for (i = 0; i <= limit; i++) {
-        if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-            fprintf(stderr, "unsupported level value: 0x%x\n", limit);
-            abort();
-        }
-        c = &cpuid_data.entries[cpuid_i++];
-
-        switch (i) {
-        case 2: {
-            /* Keep reading function 2 till all the input is received */
-            int times;
-
-            c->function = i;
-            c->flags = KVM_CPUID_FLAG_STATEFUL_FUNC |
-                       KVM_CPUID_FLAG_STATE_READ_NEXT;
-            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            times = c->eax & 0xff;
-
-            for (j = 1; j < times; ++j) {
-                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                    fprintf(stderr, "cpuid_data is full, no space for "
-                            "cpuid(eax:2):eax & 0xf = 0x%x\n", times);
-                    abort();
-                }
-                c = &cpuid_data.entries[cpuid_i++];
-                c->function = i;
-                c->flags = KVM_CPUID_FLAG_STATEFUL_FUNC;
-                cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            }
-            break;
-        }
-        case 0x1f:
-            if (env->nr_dies < 2) {
-                cpuid_i--;
-                break;
-            }
-            /* fallthrough */
-        case 4:
-        case 0xb:
-        case 0xd:
-            for (j = 0; ; j++) {
-                if (i == 0xd && j == 64) {
-                    break;
-                }
-
-                c->function = i;
-                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-                c->index = j;
-                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
-
-                if (i == 4 && c->eax == 0) {
-                    break;
-                }
-                if (i == 0xb && !(c->ecx & 0xff00)) {
-                    break;
-                }
-                if (i == 0x1f && !(c->ecx & 0xff00)) {
-                    break;
-                }
-                if (i == 0xd && c->eax == 0) {
-                    continue;
-                }
-                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                    fprintf(stderr, "cpuid_data is full, no space for "
-                            "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
-                    abort();
-                }
-                c = &cpuid_data.entries[cpuid_i++];
-            }
-            break;
-        case 0x7:
-        case 0x12:
-            for (j = 0; ; j++) {
-                c->function = i;
-                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-                c->index = j;
-                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
-
-                if (j > 1 && (c->eax & 0xf) != 1) {
-                    break;
-                }
-
-                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                    fprintf(stderr, "cpuid_data is full, no space for "
-                                "cpuid(eax:0x12,ecx:0x%x)\n", j);
-                    abort();
-                }
-                c = &cpuid_data.entries[cpuid_i++];
-            }
-            break;
-        case 0x14:
-        case 0x1d:
-        case 0x1e: {
-            uint32_t times;
-
-            c->function = i;
-            c->index = 0;
-            c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            times = c->eax;
-
-            for (j = 1; j <= times; ++j) {
-                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                    fprintf(stderr, "cpuid_data is full, no space for "
-                                "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
-                    abort();
-                }
-                c = &cpuid_data.entries[cpuid_i++];
-                c->function = i;
-                c->index = j;
-                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            }
-            break;
-        }
-        default:
-            c->function = i;
-            c->flags = 0;
-            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            if (!c->eax && !c->ebx && !c->ecx && !c->edx) {
-                /*
-                 * KVM already returns all zeroes if a CPUID entry is missing,
-                 * so we can omit it and avoid hitting KVM's 80-entry limit.
-                 */
-                cpuid_i--;
-            }
-            break;
-        }
-    }
-
-    if (limit >= 0x0a) {
-        uint32_t eax, edx;
-
-        cpu_x86_cpuid(env, 0x0a, 0, &eax, &unused, &unused, &edx);
-
-        has_architectural_pmu_version = eax & 0xff;
-        if (has_architectural_pmu_version > 0) {
-            num_architectural_pmu_gp_counters = (eax & 0xff00) >> 8;
-
-            /* Shouldn't be more than 32, since that's the number of bits
-             * available in EBX to tell us _which_ counters are available.
-             * Play it safe.
-             */
-            if (num_architectural_pmu_gp_counters > MAX_GP_COUNTERS) {
-                num_architectural_pmu_gp_counters = MAX_GP_COUNTERS;
-            }
-
-            if (has_architectural_pmu_version > 1) {
-                num_architectural_pmu_fixed_counters = edx & 0x1f;
-
-                if (num_architectural_pmu_fixed_counters > MAX_FIXED_COUNTERS) {
-                    num_architectural_pmu_fixed_counters = MAX_FIXED_COUNTERS;
-                }
-            }
-        }
-    }
-
-    cpu_x86_cpuid(env, 0x80000000, 0, &limit, &unused, &unused, &unused);
-
-    for (i = 0x80000000; i <= limit; i++) {
-        if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-            fprintf(stderr, "unsupported xlevel value: 0x%x\n", limit);
-            abort();
-        }
-        c = &cpuid_data.entries[cpuid_i++];
-
-        switch (i) {
-        case 0x8000001d:
-            /* Query for all AMD cache information leaves */
-            for (j = 0; ; j++) {
-                c->function = i;
-                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-                c->index = j;
-                cpu_x86_cpuid(env, i, j, &c->eax, &c->ebx, &c->ecx, &c->edx);
-
-                if (c->eax == 0) {
-                    break;
-                }
-                if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                    fprintf(stderr, "cpuid_data is full, no space for "
-                            "cpuid(eax:0x%x,ecx:0x%x)\n", i, j);
-                    abort();
-                }
-                c = &cpuid_data.entries[cpuid_i++];
-            }
-            break;
-        default:
-            c->function = i;
-            c->flags = 0;
-            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-            if (!c->eax && !c->ebx && !c->ecx && !c->edx) {
-                /*
-                 * KVM already returns all zeroes if a CPUID entry is missing,
-                 * so we can omit it and avoid hitting KVM's 80-entry limit.
-                 */
-                cpuid_i--;
-            }
-            break;
-        }
-    }
-
-    /* Call Centaur's CPUID instructions they are supported. */
-    if (env->cpuid_xlevel2 > 0) {
-        cpu_x86_cpuid(env, 0xC0000000, 0, &limit, &unused, &unused, &unused);
-
-        for (i = 0xC0000000; i <= limit; i++) {
-            if (cpuid_i == KVM_MAX_CPUID_ENTRIES) {
-                fprintf(stderr, "unsupported xlevel2 value: 0x%x\n", limit);
-                abort();
-            }
-            c = &cpuid_data.entries[cpuid_i++];
-
-            c->function = i;
-            c->flags = 0;
-            cpu_x86_cpuid(env, i, 0, &c->eax, &c->ebx, &c->ecx, &c->edx);
-        }
-    }
-
+    cpuid_i = kvm_x86_arch_cpuid(env, cpuid_data.entries, cpuid_i);
     cpuid_data.cpuid.nent = cpuid_i;
 
     if (((env->cpuid_version >> 8)&0xF) >= 6
diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h
index c3ef46a97a7b..cbf52c1c6d17 100644
--- a/target/i386/kvm/kvm_i386.h
+++ b/target/i386/kvm/kvm_i386.h
@@ -24,6 +24,9 @@ 
 #define kvm_ioapic_in_kernel() \
     (kvm_irqchip_in_kernel() && !kvm_irqchip_is_split())
 
+uint32_t kvm_x86_arch_cpuid(CPUX86State *env, struct kvm_cpuid_entry2 *entries,
+                            uint32_t cpuid_i);
+
 #else
 
 #define kvm_pit_in_kernel()      0