[Qemu-devel] [PULL v2 0/2] X86 queue, 2015-07-07

[Qemu-devel] [PULL v2 0/2] X86 queue, 2015-07-07

[Eduardo Habkost]

The following changes since commit 1452673888f6d7f0454276d049846c9bec659233:

  Merge remote-tracking branch 'remotes/awilliam/tags/vfio-update-20150706.0' into staging (2015-07-07 09:22:40 +0100)

are available in the git repository at:

  git://github.com/ehabkost/qemu.git tags/x86-pull-request

for you to fetch changes up to 06ef227e5158cca6710e6c268d6a7f65a5e2811b:

  target-i386: avoid overflow in the tsc-frequency property (2015-07-07 10:47:16 -0300)

----------------------------------------------------------------
X86 queue, 2015-07-07

Patch "target-i386: emulate CPUID level of real hardware" was removed after the
2015-07-03 pull request.

----------------------------------------------------------------

Jan Kiszka (1):
  i386: Introduce ARAT CPU feature

Paolo Bonzini (1):
  target-i386: avoid overflow in the tsc-frequency property

 include/hw/i386/pc.h |  7 ++++++-
 target-i386/cpu.c    | 33 ++++++++++++++++++++++++++++++++-
 target-i386/cpu.h    |  5 ++++-
 target-i386/kvm.c    |  2 ++
 4 files changed, 44 insertions(+), 3 deletions(-)

-- 
2.1.0

[Qemu-devel] [PULL v2 1/2] i386: Introduce ARAT CPU feature

[Eduardo Habkost]

From: Jan Kiszka <jan.kiszka@siemens.com>

ARAT signals that the APIC timer does not stop in power saving states.
As our APICs are emulated, it's fine to expose this feature to guests,
at least when asking for KVM host features or with CPU types that
include the flag. The exact model number that introduced the feature is
not known, but reports can be found that it's at least available since
Sandy Bridge.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 include/hw/i386/pc.h |  7 ++++++-
 target-i386/cpu.c    | 33 ++++++++++++++++++++++++++++++++-
 target-i386/cpu.h    |  3 +++
 target-i386/kvm.c    |  2 ++
 4 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 786a1d5..5daf854 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -293,7 +293,12 @@ int e820_get_num_entries(void);
 bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
 
 #define PC_COMPAT_2_3 \
-        HW_COMPAT_2_3
+        HW_COMPAT_2_3 \
+        {\
+            .driver   = TYPE_X86_CPU,\
+            .property = "arat",\
+            .value    = "off",\
+        },
 
 #define PC_COMPAT_2_2 \
         PC_COMPAT_2_3 \
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 36b07f9..b4f9461 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -286,6 +286,17 @@ static const char *cpuid_xsave_feature_name[] = {
     NULL, NULL, NULL, NULL,
 };
 
+static const char *cpuid_6_feature_name[] = {
+    NULL, NULL, "arat", NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+    NULL, NULL, NULL, NULL,
+};
+
 #define I486_FEATURES (CPUID_FP87 | CPUID_VME | CPUID_PSE)
 #define PENTIUM_FEATURES (I486_FEATURES | CPUID_DE | CPUID_TSC | \
           CPUID_MSR | CPUID_MCE | CPUID_CX8 | CPUID_MMX | CPUID_APIC)
@@ -341,6 +352,7 @@ static const char *cpuid_xsave_feature_name[] = {
           CPUID_7_0_EBX_ERMS, CPUID_7_0_EBX_INVPCID, CPUID_7_0_EBX_RTM,
           CPUID_7_0_EBX_RDSEED */
 #define TCG_APM_FEATURES 0
+#define TCG_6_EAX_FEATURES CPUID_6_EAX_ARAT
 
 
 typedef struct FeatureWordInfo {
@@ -410,6 +422,11 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .cpuid_reg = R_EAX,
         .tcg_features = 0,
     },
+    [FEAT_6_EAX] = {
+        .feat_names = cpuid_6_feature_name,
+        .cpuid_eax = 6, .cpuid_reg = R_EAX,
+        .tcg_features = TCG_6_EAX_FEATURES,
+    },
 };
 
 typedef struct X86RegisterInfo32 {
@@ -1003,6 +1020,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT2_LM | CPUID_EXT2_SYSCALL | CPUID_EXT2_NX,
         .features[FEAT_8000_0001_ECX] =
             CPUID_EXT3_LAHF_LM,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Westmere E56xx/L56xx/X56xx (Nehalem-C)",
     },
@@ -1032,6 +1051,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT3_LAHF_LM,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Xeon E312xx (Sandy Bridge)",
     },
@@ -1064,6 +1085,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT3_LAHF_LM,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Xeon E3-12xx v2 (Ivy Bridge)",
     },
@@ -1098,6 +1121,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_7_0_EBX_BMI2 | CPUID_7_0_EBX_ERMS | CPUID_7_0_EBX_INVPCID,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Core Processor (Haswell, no TSX)",
     },    {
@@ -1132,6 +1157,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_7_0_EBX_RTM,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Core Processor (Haswell)",
     },
@@ -1168,6 +1195,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_7_0_EBX_SMAP,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Core Processor (Broadwell, no TSX)",
     },
@@ -1204,6 +1233,8 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_7_0_EBX_SMAP,
         .features[FEAT_XSAVE] =
             CPUID_XSAVE_XSAVEOPT,
+        .features[FEAT_6_EAX] =
+            CPUID_6_EAX_ARAT,
         .xlevel = 0x8000000A,
         .model_id = "Intel Core Processor (Broadwell)",
     },
@@ -2359,7 +2390,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         break;
     case 6:
         /* Thermal and Power Leaf */
-        *eax = 0;
+        *eax = env->features[FEAT_6_EAX];
         *ebx = 0;
         *ecx = 0;
         *edx = 0;
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index ac39291..0bfe64c 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -415,6 +415,7 @@ typedef enum FeatureWord {
     FEAT_KVM,           /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */
     FEAT_SVM,           /* CPUID[8000_000A].EDX */
     FEAT_XSAVE,         /* CPUID[EAX=0xd,ECX=1].EAX */
+    FEAT_6_EAX,         /* CPUID[6].EAX */
     FEATURE_WORDS,
 } FeatureWord;
 
@@ -580,6 +581,8 @@ typedef uint32_t FeatureWordArray[FEATURE_WORDS];
 #define CPUID_XSAVE_XGETBV1    (1U << 2)
 #define CPUID_XSAVE_XSAVES     (1U << 3)
 
+#define CPUID_6_EAX_ARAT       (1U << 2)
+
 /* CPUID[0x80000007].EDX flags: */
 #define CPUID_APM_INVTSC       (1U << 8)
 
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 9038bf7..066d03d 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -238,6 +238,8 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function,
         if (!kvm_irqchip_in_kernel()) {
             ret &= ~CPUID_EXT_X2APIC;
         }
+    } else if (function == 6 && reg == R_EAX) {
+        ret |= CPUID_6_EAX_ARAT; /* safe to allow because of emulated APIC */
     } 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:
-- 
2.1.0

[Qemu-devel] [PULL v2 2/2] target-i386: avoid overflow in the tsc-frequency property

[Eduardo Habkost]

From: Paolo Bonzini <pbonzini@redhat.com>

The TSC frequency fits comfortably in an int when expressed in kHz,
but it may overflow when converted to Hz.  In this case,
tsc-frequency returns a negative value because x86_cpuid_get_tsc_freq
does a 32-bit multiplication before assigning to int64_t.

For simplicity just make tsc_khz a 64-bit value.

Spotted by Coverity.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 target-i386/cpu.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index 0bfe64c..14dced0 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -962,7 +962,7 @@ typedef struct CPUX86State {
     uint8_t has_error_code;
     uint32_t sipi_vector;
     bool tsc_valid;
-    int tsc_khz;
+    int64_t tsc_khz;
     void *kvm_xsave_buf;
 
     uint64_t mcg_cap;
-- 
2.1.0

Re: [Qemu-devel] [PULL v2 0/2] X86 queue, 2015-07-07

[Peter Maydell]

On 7 July 2015 at 15:47, Eduardo Habkost <ehabkost@redhat.com> wrote:
> The following changes since commit 1452673888f6d7f0454276d049846c9bec659233:
>
>   Merge remote-tracking branch 'remotes/awilliam/tags/vfio-update-20150706.0' into staging (2015-07-07 09:22:40 +0100)
>
> are available in the git repository at:
>
>   git://github.com/ehabkost/qemu.git tags/x86-pull-request
>
> for you to fetch changes up to 06ef227e5158cca6710e6c268d6a7f65a5e2811b:
>
>   target-i386: avoid overflow in the tsc-frequency property (2015-07-07 10:47:16 -0300)
>
> ----------------------------------------------------------------
> X86 queue, 2015-07-07
>
> Patch "target-i386: emulate CPUID level of real hardware" was removed after the
> 2015-07-03 pull request.
>
> ----------------------------------------------------------------

Applied, thanks.

-- PMM