[Qemu-devel] v3: KVM: support for 'count' in CPUID functions 4, 0xb and 0xd

[Qemu-devel] v3: KVM: support for 'count' in CPUID functions 4, 0xb and 0xd

[Amit Shah]

These patches add support for cpuid functions that take a 'count' parameter
in addition to the function number. With these patches, KVM can run a VM
started with a newer CPU type (coreduo, core2duo). These patches also pave
way for a "host" CPU type, where we could pass the CPU type of the current
host to the VM.

v3 uses the as-yet unused KVM_SET_CPUID2 interface, which was written to
support this functionality. Since we rely on kernel versions 2.6.25 at a
minimum for KVM and the SET_CPUID2 interface was introduced in 2.6.25, we're
safe with this.

Please apply.

[Qemu-devel] [PATCH 1/2] KVM: CPUID takes ecx as input value for some functions

[Amit Shah]

The CPUID instruction takes the value of ECX as an input parameter
in addition to the value of EAX as the count for functions 4, 0xb
and 0xd. Make sure we pass the value to the instruction.

Also convert to the qemu-style whitespace for the surrounding code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 qemu/target-i386/cpu.h       |    2 +-
 qemu/target-i386/helper.c    |   34 +++++++++++++++++-----------------
 qemu/target-i386/kvm.c       |    8 ++++----
 qemu/target-i386/op_helper.c |    2 +-
 4 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/qemu/target-i386/cpu.h b/qemu/target-i386/cpu.h
index 944e386..d9834db 100644
--- a/qemu/target-i386/cpu.h
+++ b/qemu/target-i386/cpu.h
@@ -743,7 +743,7 @@ int cpu_x86_signal_handler(int host_signum, void *pinfo,
 int cpu_x86_handle_mmu_fault(CPUX86State *env, target_ulong addr,
                              int is_write, int mmu_idx, int is_softmmu);
 void cpu_x86_set_a20(CPUX86State *env, int a20_state);
-void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
+void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
                    uint32_t *eax, uint32_t *ebx,
                    uint32_t *ecx, uint32_t *edx);
 
diff --git a/qemu/target-i386/helper.c b/qemu/target-i386/helper.c
index cda0390..4c1e541 100644
--- a/qemu/target-i386/helper.c
+++ b/qemu/target-i386/helper.c
@@ -1377,7 +1377,8 @@ static void breakpoint_handler(CPUState *env)
 }
 #endif /* !CONFIG_USER_ONLY */
 
-static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
+static void host_cpuid(uint32_t function, uint32_t count,
+                       uint32_t *eax, uint32_t *ebx,
                        uint32_t *ecx, uint32_t *edx)
 {
 #if defined(CONFIG_KVM) || defined(USE_KVM)
@@ -1385,19 +1386,19 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
 
 #ifdef __x86_64__
     asm volatile("cpuid"
-		 : "=a"(vec[0]), "=b"(vec[1]),
-		   "=c"(vec[2]), "=d"(vec[3])
-		 : "0"(function) : "cc");
+                 : "=a"(vec[0]), "=b"(vec[1]),
+                   "=c"(vec[2]), "=d"(vec[3])
+                 : "0"(function), "c"(count) : "cc");
 #else
     asm volatile("pusha \n\t"
-		 "cpuid \n\t"
-		 "mov %%eax, 0(%1) \n\t"
-		 "mov %%ebx, 4(%1) \n\t"
-		 "mov %%ecx, 8(%1) \n\t"
-		 "mov %%edx, 12(%1) \n\t"
-		 "popa"
-		 : : "a"(function), "S"(vec)
-		 : "memory", "cc");
+                 "cpuid \n\t"
+                 "mov %%eax, 0(%1) \n\t"
+                 "mov %%ebx, 4(%1) \n\t"
+                 "mov %%ecx, 8(%1) \n\t"
+                 "mov %%edx, 12(%1) \n\t"
+                 "popa"
+                 : : "a"(function), "c"(count), "S"(vec)
+                 : "memory", "cc");
 #endif
 
     if (eax)
@@ -1411,7 +1412,7 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
 #endif
 }
 
-void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
+void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
                    uint32_t *eax, uint32_t *ebx,
                    uint32_t *ecx, uint32_t *edx)
 {
@@ -1436,7 +1437,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
          * actuall cpu, and say goodbye to migration between different vendors
          * is you use compatibility mode. */
         if (kvm_enabled())
-            host_cpuid(0, NULL, ebx, ecx, edx);
+            host_cpuid(0, 0, NULL, ebx, ecx, edx);
         break;
     case 1:
         *eax = env->cpuid_version;
@@ -1457,7 +1458,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
         break;
     case 4:
         /* cache info: needed for Core compatibility */
-        switch (*ecx) {
+        switch (count) {
             case 0: /* L1 dcache info */
                 *eax = 0x0000121;
                 *ebx = 0x1c0003f;
@@ -1483,7 +1484,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
                 *edx = 0;
                 break;
         }
-
         break;
     case 5:
         /* mwait info: needed for Core compatibility */
@@ -1528,7 +1528,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
         if (kvm_enabled()) {
             uint32_t h_eax, h_edx;
 
-            host_cpuid(0x80000001, &h_eax, NULL, NULL, &h_edx);
+            host_cpuid(index, 0, &h_eax, NULL, NULL, &h_edx);
 
             /* disable CPU features that the host does not support */
 
diff --git a/qemu/target-i386/kvm.c b/qemu/target-i386/kvm.c
index f87bf36..bef3150 100644
--- a/qemu/target-i386/kvm.c
+++ b/qemu/target-i386/kvm.c
@@ -44,13 +44,13 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     cpuid_i = 0;
 
-    cpu_x86_cpuid(env, 0, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, 0, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0; i <= limit; i++) {
         struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
 
-        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
+        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
         c->eax = eax;
         c->ebx = ebx;
@@ -58,13 +58,13 @@ int kvm_arch_init_vcpu(CPUState *env)
         c->edx = edx;
     }
 
-    cpu_x86_cpuid(env, 0x80000000, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, 0x80000000, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0x80000000; i <= limit; i++) {
         struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
 
-        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
+        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
         c->eax = eax;
         c->ebx = ebx;
diff --git a/qemu/target-i386/op_helper.c b/qemu/target-i386/op_helper.c
index 6e0e32e..74ba643 100644
--- a/qemu/target-i386/op_helper.c
+++ b/qemu/target-i386/op_helper.c
@@ -1898,7 +1898,7 @@ void helper_cpuid(void)
 
     helper_svm_check_intercept_param(SVM_EXIT_CPUID, 0);
 
-    cpu_x86_cpuid(env, (uint32_t)EAX, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, (uint32_t)EAX, (uint32_t)ECX, &eax, &ebx, &ecx, &edx);
     EAX = eax;
     EBX = ebx;
     ECX = ecx;
-- 
1.6.0.6

[Qemu-devel] [PATCH 2/2] KVM: Fetch sub-leaf cpuid values for functions 4, 0xb, 0xd.

[Amit Shah]

CPUID functions 4, 0xb and 0xd have sub-leaf values which depend on the
input value of ECX. Store these values as well.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 qemu/target-i386/kvm.c |   48 ++++++++++++++++++++++++++++++++++--------------
 1 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/qemu/target-i386/kvm.c b/qemu/target-i386/kvm.c
index bef3150..0f20b9c 100644
--- a/qemu/target-i386/kvm.c
+++ b/qemu/target-i386/kvm.c
@@ -36,10 +36,10 @@
 int kvm_arch_init_vcpu(CPUState *env)
 {
     struct {
-        struct kvm_cpuid cpuid;
-        struct kvm_cpuid_entry entries[100];
+        struct kvm_cpuid2 cpuid;
+        struct kvm_cpuid_entry2 entries[100];
     } __attribute__((packed)) cpuid_data;
-    uint32_t limit, i, cpuid_i;
+    uint32_t limit, i, j, cpuid_i;
     uint32_t eax, ebx, ecx, edx;
 
     cpuid_i = 0;
@@ -48,21 +48,41 @@ int kvm_arch_init_vcpu(CPUState *env)
     limit = eax;
 
     for (i = 0; i <= limit; i++) {
-        struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
-
-        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
-        c->function = i;
-        c->eax = eax;
-        c->ebx = ebx;
-        c->ecx = ecx;
-        c->edx = edx;
+        struct kvm_cpuid_entry2 *c = &cpuid_data.entries[cpuid_i++];
+
+        if (i == 4 || i == 0xb || i == 0xd) {
+            for (j = 0; ; j++) {
+                cpu_x86_cpuid(env, i, j, &eax, &ebx, &ecx, &edx);
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                c->index = j;
+                c->eax = eax;
+                c->ebx = ebx;
+                c->ecx = ecx;
+                c->edx = edx;
+                c = &cpuid_data.entries[++cpuid_i];
+
+                if (i == 4 && eax == 0)
+                    break;
+                if (i == 0xb && !(ecx & 0xff00))
+                    break;
+                if (i == 0xd && eax == 0)
+                    break;
+            }
+        } else {
+            cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
+            c->function = i;
+            c->eax = eax;
+            c->ebx = ebx;
+            c->ecx = ecx;
+            c->edx = edx;
+        }
     }
-
     cpu_x86_cpuid(env, 0x80000000, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0x80000000; i <= limit; i++) {
-        struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
+        struct kvm_cpuid_entry2 *c = &cpuid_data.entries[cpuid_i++];
 
         cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
@@ -74,7 +94,7 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     cpuid_data.cpuid.nent = cpuid_i;
 
-    return kvm_vcpu_ioctl(env, KVM_SET_CPUID, &cpuid_data);
+    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
 }
 
 static int kvm_has_msr_star(CPUState *env)
-- 
1.6.0.6

[Qemu-devel] Re: v3: KVM: support for 'count' in CPUID functions 4, 0xb and 0xd

[Avi Kivity]

Amit Shah wrote:
> These patches add support for cpuid functions that take a 'count' parameter
> in addition to the function number. With these patches, KVM can run a VM
> started with a newer CPU type (coreduo, core2duo). These patches also pave
> way for a "host" CPU type, where we could pass the CPU type of the current
> host to the VM.
>
> v3 uses the as-yet unused KVM_SET_CPUID2 interface, which was written to
> support this functionality. Since we rely on kernel versions 2.6.25 at a
> minimum for KVM and the SET_CPUID2 interface was introduced in 2.6.25, we're
> safe with this.
>
>   

Looks good.  Note that function 2 also needs special treatment.

-- 
error compiling committee.c: too many arguments to function

[Qemu-devel] Re: v3: KVM: support for 'count' in CPUID functions 4, 0xb and 0xd

[Amit Shah]

On Thu, Jan 15, 2009 at 11:54:09AM +0200, Avi Kivity wrote:
> Amit Shah wrote:
>> These patches add support for cpuid functions that take a 'count' parameter
>> in addition to the function number. With these patches, KVM can run a VM
>> started with a newer CPU type (coreduo, core2duo). These patches also pave
>> way for a "host" CPU type, where we could pass the CPU type of the current
>> host to the VM.
>>
>> v3 uses the as-yet unused KVM_SET_CPUID2 interface, which was written to
>> support this functionality. Since we rely on kernel versions 2.6.25 at a
>> minimum for KVM and the SET_CPUID2 interface was introduced in 2.6.25, we're
>> safe with this.
>
> Looks good.  Note that function 2 also needs special treatment.

Yes; I'll add that support as well.

Thanks,
Amit

[Qemu-devel] Re: [PATCH 1/2] KVM: CPUID takes ecx as input value for some functions

[Anthony Liguori]

Amit Shah wrote:
> The CPUID instruction takes the value of ECX as an input parameter
> in addition to the value of EAX as the count for functions 4, 0xb
> and 0xd. Make sure we pass the value to the instruction.
>
> Also convert to the qemu-style whitespace for the surrounding code.
>
> Signed-off-by: Amit Shah <amit.shah@redhat.com>
> ---
>  qemu/target-i386/cpu.h       |    2 +-
>  qemu/target-i386/helper.c    |   34 +++++++++++++++++-----------------
>  qemu/target-i386/kvm.c       |    8 ++++----
>  qemu/target-i386/op_helper.c |    2 +-
>  4 files changed, 23 insertions(+), 23 deletions(-)
>   

Please resubmit against qemu (not kvm-userspace) and I'll apply.

Regards,

Anthony Liguori

> diff --git a/qemu/target-i386/cpu.h b/qemu/target-i386/cpu.h
> index 944e386..d9834db 100644
> --- a/qemu/target-i386/cpu.h
> +++ b/qemu/target-i386/cpu.h
> @@ -743,7 +743,7 @@ int cpu_x86_signal_handler(int host_signum, void *pinfo,
>  int cpu_x86_handle_mmu_fault(CPUX86State *env, target_ulong addr,
>                               int is_write, int mmu_idx, int is_softmmu);
>  void cpu_x86_set_a20(CPUX86State *env, int a20_state);
> -void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> +void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
>                     uint32_t *eax, uint32_t *ebx,
>                     uint32_t *ecx, uint32_t *edx);
>
> diff --git a/qemu/target-i386/helper.c b/qemu/target-i386/helper.c
> index cda0390..4c1e541 100644
> --- a/qemu/target-i386/helper.c
> +++ b/qemu/target-i386/helper.c
> @@ -1377,7 +1377,8 @@ static void breakpoint_handler(CPUState *env)
>  }
>  #endif /* !CONFIG_USER_ONLY */
>
> -static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
> +static void host_cpuid(uint32_t function, uint32_t count,
> +                       uint32_t *eax, uint32_t *ebx,
>                         uint32_t *ecx, uint32_t *edx)
>  {
>  #if defined(CONFIG_KVM) || defined(USE_KVM)
> @@ -1385,19 +1386,19 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
>
>  #ifdef __x86_64__
>      asm volatile("cpuid"
> -		 : "=a"(vec[0]), "=b"(vec[1]),
> -		   "=c"(vec[2]), "=d"(vec[3])
> -		 : "0"(function) : "cc");
> +                 : "=a"(vec[0]), "=b"(vec[1]),
> +                   "=c"(vec[2]), "=d"(vec[3])
> +                 : "0"(function), "c"(count) : "cc");
>  #else
>      asm volatile("pusha \n\t"
> -		 "cpuid \n\t"
> -		 "mov %%eax, 0(%1) \n\t"
> -		 "mov %%ebx, 4(%1) \n\t"
> -		 "mov %%ecx, 8(%1) \n\t"
> -		 "mov %%edx, 12(%1) \n\t"
> -		 "popa"
> -		 : : "a"(function), "S"(vec)
> -		 : "memory", "cc");
> +                 "cpuid \n\t"
> +                 "mov %%eax, 0(%1) \n\t"
> +                 "mov %%ebx, 4(%1) \n\t"
> +                 "mov %%ecx, 8(%1) \n\t"
> +                 "mov %%edx, 12(%1) \n\t"
> +                 "popa"
> +                 : : "a"(function), "c"(count), "S"(vec)
> +                 : "memory", "cc");
>  #endif
>
>      if (eax)
> @@ -1411,7 +1412,7 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
>  #endif
>  }
>
> -void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> +void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
>                     uint32_t *eax, uint32_t *ebx,
>                     uint32_t *ecx, uint32_t *edx)
>  {
> @@ -1436,7 +1437,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
>           * actuall cpu, and say goodbye to migration between different vendors
>           * is you use compatibility mode. */
>          if (kvm_enabled())
> -            host_cpuid(0, NULL, ebx, ecx, edx);
> +            host_cpuid(0, 0, NULL, ebx, ecx, edx);
>          break;
>      case 1:
>          *eax = env->cpuid_version;
> @@ -1457,7 +1458,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
>          break;
>      case 4:
>          /* cache info: needed for Core compatibility */
> -        switch (*ecx) {
> +        switch (count) {
>              case 0: /* L1 dcache info */
>                  *eax = 0x0000121;
>                  *ebx = 0x1c0003f;
> @@ -1483,7 +1484,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
>                  *edx = 0;
>                  break;
>          }
> -
>          break;
>      case 5:
>          /* mwait info: needed for Core compatibility */
> @@ -1528,7 +1528,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
>          if (kvm_enabled()) {
>              uint32_t h_eax, h_edx;
>
> -            host_cpuid(0x80000001, &h_eax, NULL, NULL, &h_edx);
> +            host_cpuid(index, 0, &h_eax, NULL, NULL, &h_edx);
>
>              /* disable CPU features that the host does not support */
>
> diff --git a/qemu/target-i386/kvm.c b/qemu/target-i386/kvm.c
> index f87bf36..bef3150 100644
> --- a/qemu/target-i386/kvm.c
> +++ b/qemu/target-i386/kvm.c
> @@ -44,13 +44,13 @@ int kvm_arch_init_vcpu(CPUState *env)
>
>      cpuid_i = 0;
>
> -    cpu_x86_cpuid(env, 0, &eax, &ebx, &ecx, &edx);
> +    cpu_x86_cpuid(env, 0, 0, &eax, &ebx, &ecx, &edx);
>      limit = eax;
>
>      for (i = 0; i <= limit; i++) {
>          struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
>
> -        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
> +        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
>          c->function = i;
>          c->eax = eax;
>          c->ebx = ebx;
> @@ -58,13 +58,13 @@ int kvm_arch_init_vcpu(CPUState *env)
>          c->edx = edx;
>      }
>
> -    cpu_x86_cpuid(env, 0x80000000, &eax, &ebx, &ecx, &edx);
> +    cpu_x86_cpuid(env, 0x80000000, 0, &eax, &ebx, &ecx, &edx);
>      limit = eax;
>
>      for (i = 0x80000000; i <= limit; i++) {
>          struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
>
> -        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
> +        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
>          c->function = i;
>          c->eax = eax;
>          c->ebx = ebx;
> diff --git a/qemu/target-i386/op_helper.c b/qemu/target-i386/op_helper.c
> index 6e0e32e..74ba643 100644
> --- a/qemu/target-i386/op_helper.c
> +++ b/qemu/target-i386/op_helper.c
> @@ -1898,7 +1898,7 @@ void helper_cpuid(void)
>
>      helper_svm_check_intercept_param(SVM_EXIT_CPUID, 0);
>
> -    cpu_x86_cpuid(env, (uint32_t)EAX, &eax, &ebx, &ecx, &edx);
> +    cpu_x86_cpuid(env, (uint32_t)EAX, (uint32_t)ECX, &eax, &ebx, &ecx, &edx);
>      EAX = eax;
>      EBX = ebx;
>      ECX = ecx;
>   

[Qemu-devel] KVM: support for 'count' in CPUID functions 4, 0xb and 0xd

[Amit Shah]

Hi Anthony,

Here are the patches based on qemu-cvs.

Thanks,
Amit.

[Qemu-devel] [PATCH 1/2] KVM: CPUID takes ecx as input value for some functions

[Amit Shah]

The CPUID instruction takes the value of ECX as an input parameter
in addition to the value of EAX as the count for functions 4, 0xb
and 0xd. Make sure we pass the value to the instruction.

Also convert to the qemu-style whitespace for the surrounding code.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 qemu/target-i386/cpu.h       |    2 +-
 qemu/target-i386/helper.c    |   34 +++++++++++++++++-----------------
 qemu/target-i386/kvm.c       |    8 ++++----
 qemu/target-i386/op_helper.c |    2 +-
 4 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/qemu/target-i386/cpu.h b/qemu/target-i386/cpu.h
index 7803560..cd773a0 100644
--- a/qemu/target-i386/cpu.h
+++ b/qemu/target-i386/cpu.h
@@ -742,7 +742,7 @@ int cpu_x86_signal_handler(int host_signum, void *pinfo,
 int cpu_x86_handle_mmu_fault(CPUX86State *env, target_ulong addr,
                              int is_write, int mmu_idx, int is_softmmu);
 void cpu_x86_set_a20(CPUX86State *env, int a20_state);
-void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
+void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
                    uint32_t *eax, uint32_t *ebx,
                    uint32_t *ecx, uint32_t *edx);
 
diff --git a/qemu/target-i386/helper.c b/qemu/target-i386/helper.c
index a28ab93..9382fbf 100644
--- a/qemu/target-i386/helper.c
+++ b/qemu/target-i386/helper.c
@@ -1370,7 +1370,8 @@ static void breakpoint_handler(CPUState *env)
 }
 #endif /* !CONFIG_USER_ONLY */
 
-static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
+static void host_cpuid(uint32_t function, uint32_t count,
+                       uint32_t *eax, uint32_t *ebx,
                        uint32_t *ecx, uint32_t *edx)
 {
 #if defined(CONFIG_KVM)
@@ -1378,19 +1379,19 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
 
 #ifdef __x86_64__
     asm volatile("cpuid"
-		 : "=a"(vec[0]), "=b"(vec[1]),
-		   "=c"(vec[2]), "=d"(vec[3])
-		 : "0"(function) : "cc");
+                 : "=a"(vec[0]), "=b"(vec[1]),
+                   "=c"(vec[2]), "=d"(vec[3])
+                 : "0"(function), "c"(count) : "cc");
 #else
     asm volatile("pusha \n\t"
-		 "cpuid \n\t"
-		 "mov %%eax, 0(%1) \n\t"
-		 "mov %%ebx, 4(%1) \n\t"
-		 "mov %%ecx, 8(%1) \n\t"
-		 "mov %%edx, 12(%1) \n\t"
-		 "popa"
-		 : : "a"(function), "S"(vec)
-		 : "memory", "cc");
+                 "cpuid \n\t"
+                 "mov %%eax, 0(%1) \n\t"
+                 "mov %%ebx, 4(%1) \n\t"
+                 "mov %%ecx, 8(%1) \n\t"
+                 "mov %%edx, 12(%1) \n\t"
+                 "popa"
+                 : : "a"(function), "c"(count), "S"(vec)
+                 : "memory", "cc");
 #endif
 
     if (eax)
@@ -1404,7 +1405,7 @@ static void host_cpuid(uint32_t function, uint32_t *eax, uint32_t *ebx,
 #endif
 }
 
-void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
+void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
                    uint32_t *eax, uint32_t *ebx,
                    uint32_t *ecx, uint32_t *edx)
 {
@@ -1429,7 +1430,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
          * actuall cpu, and say goodbye to migration between different vendors
          * is you use compatibility mode. */
         if (kvm_enabled())
-            host_cpuid(0, NULL, ebx, ecx, edx);
+            host_cpuid(0, 0, NULL, ebx, ecx, edx);
         break;
     case 1:
         *eax = env->cpuid_version;
@@ -1450,7 +1451,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
         break;
     case 4:
         /* cache info: needed for Core compatibility */
-        switch (*ecx) {
+        switch (count) {
             case 0: /* L1 dcache info */
                 *eax = 0x0000121;
                 *ebx = 0x1c0003f;
@@ -1476,7 +1477,6 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
                 *edx = 0;
                 break;
         }
-
         break;
     case 5:
         /* mwait info: needed for Core compatibility */
@@ -1521,7 +1521,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
         if (kvm_enabled()) {
             uint32_t h_eax, h_edx;
 
-            host_cpuid(0x80000001, &h_eax, NULL, NULL, &h_edx);
+            host_cpuid(index, 0, &h_eax, NULL, NULL, &h_edx);
 
             /* disable CPU features that the host does not support */
 
diff --git a/qemu/target-i386/kvm.c b/qemu/target-i386/kvm.c
index 2412ae4..7c84e24 100644
--- a/qemu/target-i386/kvm.c
+++ b/qemu/target-i386/kvm.c
@@ -44,13 +44,13 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     cpuid_i = 0;
 
-    cpu_x86_cpuid(env, 0, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, 0, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0; i <= limit; i++) {
         struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
 
-        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
+        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
         c->eax = eax;
         c->ebx = ebx;
@@ -58,13 +58,13 @@ int kvm_arch_init_vcpu(CPUState *env)
         c->edx = edx;
     }
 
-    cpu_x86_cpuid(env, 0x80000000, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, 0x80000000, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0x80000000; i <= limit; i++) {
         struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
 
-        cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
+        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
         c->eax = eax;
         c->ebx = ebx;
diff --git a/qemu/target-i386/op_helper.c b/qemu/target-i386/op_helper.c
index 6e0e32e..74ba643 100644
--- a/qemu/target-i386/op_helper.c
+++ b/qemu/target-i386/op_helper.c
@@ -1898,7 +1898,7 @@ void helper_cpuid(void)
 
     helper_svm_check_intercept_param(SVM_EXIT_CPUID, 0);
 
-    cpu_x86_cpuid(env, (uint32_t)EAX, &eax, &ebx, &ecx, &edx);
+    cpu_x86_cpuid(env, (uint32_t)EAX, (uint32_t)ECX, &eax, &ebx, &ecx, &edx);
     EAX = eax;
     EBX = ebx;
     ECX = ecx;
-- 
1.6.0.6

[Qemu-devel] [PATCH 2/2] KVM: Fetch sub-leaf cpuid values for functions 4, 0xb, 0xd.

[Amit Shah]

CPUID functions 4, 0xb and 0xd have sub-leaf values which depend on the
input value of ECX. Store these values as well.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 qemu/target-i386/kvm.c |   48 ++++++++++++++++++++++++++++++++++--------------
 1 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/qemu/target-i386/kvm.c b/qemu/target-i386/kvm.c
index 7c84e24..1482a26 100644
--- a/qemu/target-i386/kvm.c
+++ b/qemu/target-i386/kvm.c
@@ -36,10 +36,10 @@
 int kvm_arch_init_vcpu(CPUState *env)
 {
     struct {
-        struct kvm_cpuid cpuid;
-        struct kvm_cpuid_entry entries[100];
+        struct kvm_cpuid2 cpuid;
+        struct kvm_cpuid_entry2 entries[100];
     } __attribute__((packed)) cpuid_data;
-    uint32_t limit, i, cpuid_i;
+    uint32_t limit, i, j, cpuid_i;
     uint32_t eax, ebx, ecx, edx;
 
     cpuid_i = 0;
@@ -48,21 +48,41 @@ int kvm_arch_init_vcpu(CPUState *env)
     limit = eax;
 
     for (i = 0; i <= limit; i++) {
-        struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
-
-        cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
-        c->function = i;
-        c->eax = eax;
-        c->ebx = ebx;
-        c->ecx = ecx;
-        c->edx = edx;
+        struct kvm_cpuid_entry2 *c = &cpuid_data.entries[cpuid_i++];
+
+        if (i == 4 || i == 0xb || i == 0xd) {
+            for (j = 0; ; j++) {
+                cpu_x86_cpuid(env, i, j, &eax, &ebx, &ecx, &edx);
+                c->function = i;
+                c->flags = KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
+                c->index = j;
+                c->eax = eax;
+                c->ebx = ebx;
+                c->ecx = ecx;
+                c->edx = edx;
+                c = &cpuid_data.entries[++cpuid_i];
+
+                if (i == 4 && eax == 0)
+                    break;
+                if (i == 0xb && !(ecx & 0xff00))
+                    break;
+                if (i == 0xd && eax == 0)
+                    break;
+            }
+        } else {
+            cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
+            c->function = i;
+            c->eax = eax;
+            c->ebx = ebx;
+            c->ecx = ecx;
+            c->edx = edx;
+        }
     }
-
     cpu_x86_cpuid(env, 0x80000000, 0, &eax, &ebx, &ecx, &edx);
     limit = eax;
 
     for (i = 0x80000000; i <= limit; i++) {
-        struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
+        struct kvm_cpuid_entry2 *c = &cpuid_data.entries[cpuid_i++];
 
         cpu_x86_cpuid(env, i, 0, &eax, &ebx, &ecx, &edx);
         c->function = i;
@@ -74,7 +94,7 @@ int kvm_arch_init_vcpu(CPUState *env)
 
     cpuid_data.cpuid.nent = cpuid_i;
 
-    return kvm_vcpu_ioctl(env, KVM_SET_CPUID, &cpuid_data);
+    return kvm_vcpu_ioctl(env, KVM_SET_CPUID2, &cpuid_data);
 }
 
 static int kvm_has_msr_star(CPUState *env)
-- 
1.6.0.6