[Qemu-devel] [PATCH RFC v2 0/2] Initial support for Microsoft Hyper-V.

[Qemu-devel] [PATCH RFC v2 0/2] Initial support for Microsoft Hyper-V.

[Vadim Rozenfeld]

With the following series of patches we are starting to implement
some basic Microsoft Hyper-V Enlightenment functionality. This series
is mostly about adding support for relaxed timing, spinlock,
and virtual apic.

For more Hyper-V related information please see:
"Hypervisor Functional Specification v2.0: For Windows Server 2008 R2" at
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=18673

Changelog:
 v2->v1
  - remove KVM_CAP_IRQCHIP ifdef,
  - remove CONFIG_HYPERV config option,
  - move KVM leaves to new location (0x40000100),
  - cosmetic changes.
 v0->v1
  - move hyper-v parameters under cpu category,
  - move hyper-v stuff to target-i386 directory,
  - make CONFIG_HYPERV enabled by default for
    i386-softmmu and x86_64-softmmu configurations,
  - rearrange the patches from v0,
  - set HV_X64_MSR_HYPERCALL, HV_X64_MSR_GUEST_OS_ID,
    and HV_X64_MSR_APIC_ASSIST_PAGE to 0 on system reset.



Vadim Rozenfeld (2):
  hyper-v: introduce Hyper-V support infrastructure.
  hyper-v: initialize Hyper-V CPUID leaves.

 Makefile.target      |    2 +
 target-i386/cpuid.c  |   14 +++++++++
 target-i386/hyperv.c |   65 ++++++++++++++++++++++++++++++++++++++++++++
 target-i386/hyperv.h |   37 +++++++++++++++++++++++++
 target-i386/kvm.c    |   73 ++++++++++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 189 insertions(+), 2 deletions(-)
 create mode 100644 target-i386/hyperv.c
 create mode 100644 target-i386/hyperv.h

-- 
1.7.4.4

[Qemu-devel] [PATCH 1/2] [PATCH RFC v2 1/2] hyper-v: introduce Hyper-V support infrastructure.

[Vadim Rozenfeld]

---
 Makefile.target      |    2 +
 target-i386/cpuid.c  |   14 ++++++++++
 target-i386/hyperv.c |   65 ++++++++++++++++++++++++++++++++++++++++++++++++++
 target-i386/hyperv.h |   37 ++++++++++++++++++++++++++++
 4 files changed, 118 insertions(+), 0 deletions(-)
 create mode 100644 target-i386/hyperv.c
 create mode 100644 target-i386/hyperv.h

diff --git a/Makefile.target b/Makefile.target
index 325f26e..446fabc 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -202,6 +202,8 @@ obj-$(CONFIG_NO_KVM) += kvm-stub.o
 obj-y += memory.o
 LIBS+=-lz
 
+obj-i386-y +=hyperv.o
+
 QEMU_CFLAGS += $(VNC_TLS_CFLAGS)
 QEMU_CFLAGS += $(VNC_SASL_CFLAGS)
 QEMU_CFLAGS += $(VNC_JPEG_CFLAGS)
diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
index 1e8bcff..261c168 100644
--- a/target-i386/cpuid.c
+++ b/target-i386/cpuid.c
@@ -27,6 +27,8 @@
 #include "qemu-option.h"
 #include "qemu-config.h"
 
+#include "hyperv.h"
+
 /* feature flags taken from "Intel Processor Identification and the CPUID
  * Instruction" and AMD's "CPUID Specification".  In cases of disagreement
  * between feature naming conventions, aliases may be added.
@@ -716,6 +718,14 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
                     goto error;
                 }
                 x86_cpu_def->tsc_khz = tsc_freq / 1000;
+            } else if (!strcmp(featurestr, "hv_spinlocks")) {
+               char *err;
+               numvalue = strtoul(val, &err, 0);
+               if (!*val || *err) {
+                    fprintf(stderr, "bad numerical value %s\n", val);
+                    goto error;
+                }
+                hyperv_set_spinlock_retries(numvalue);
             } else {
                 fprintf(stderr, "unrecognized feature %s\n", featurestr);
                 goto error;
@@ -724,6 +734,10 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
             check_cpuid = 1;
         } else if (!strcmp(featurestr, "enforce")) {
             check_cpuid = enforce_cpuid = 1;
+        } else if (!strcmp(featurestr, "hv_relaxed")) {
+            hyperv_enable_relaxed_timing(true);
+        } else if (!strcmp(featurestr, "hv_vapic")) {
+            hyperv_enable_vapic_recommended(true);            
         } else {
             fprintf(stderr, "feature string `%s' not in format (+feature|-feature|feature=xyz)\n", featurestr);
             goto error;
diff --git a/target-i386/hyperv.c b/target-i386/hyperv.c
new file mode 100644
index 0000000..b2e57ad
--- /dev/null
+++ b/target-i386/hyperv.c
@@ -0,0 +1,65 @@
+/*
+ * QEMU Hyper-V support
+ *
+ * Copyright Red Hat, Inc. 2011
+ *
+ * Author: Vadim Rozenfeld     <vrozenfe@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "hyperv.h"
+
+static bool hyperv_vapic;
+static bool hyperv_relaxed_timing;
+static int hyperv_spinlock_attempts = HYPERV_SPINLOCK_NEVER_RETRY;
+
+void hyperv_enable_vapic_recommended(bool val)
+{
+    hyperv_vapic = val;
+}
+
+void hyperv_enable_relaxed_timing(bool val)
+{
+    hyperv_relaxed_timing = val;
+}
+
+void hyperv_set_spinlock_retries(int val)
+{
+    hyperv_spinlock_attempts = val;
+    if (hyperv_spinlock_attempts < 0xFFF) {
+        hyperv_spinlock_attempts = 0xFFF;
+    }
+}
+
+bool hyperv_enabled(void)
+{
+    return hyperv_hypercall_available() || hyperv_relaxed_timing_enabled();
+}
+
+bool hyperv_hypercall_available(void)
+{
+    if (hyperv_vapic ||
+        (hyperv_spinlock_attempts != HYPERV_SPINLOCK_NEVER_RETRY)) {
+      return true;
+    }
+    return false;
+}
+
+bool hyperv_vapic_recommended(void)
+{
+    return hyperv_vapic;
+}
+
+bool hyperv_relaxed_timing_enabled(void)
+{
+    return hyperv_relaxed_timing;
+}
+
+int hyperv_get_spinlock_retries(void)
+{
+    return hyperv_spinlock_attempts;
+}
+
diff --git a/target-i386/hyperv.h b/target-i386/hyperv.h
new file mode 100644
index 0000000..0d742f8
--- /dev/null
+++ b/target-i386/hyperv.h
@@ -0,0 +1,37 @@
+/*
+ * QEMU Hyper-V support
+ *
+ * Copyright Red Hat, Inc. 2011
+ *
+ * Author: Vadim Rozenfeld     <vrozenfe@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef QEMU_HW_HYPERV_H
+#define QEMU_HW_HYPERV_H 1
+
+#include "qemu-common.h"
+#include <asm/hyperv.h>
+
+#ifndef HYPERV_SPINLOCK_NEVER_RETRY
+#define HYPERV_SPINLOCK_NEVER_RETRY             0xFFFFFFFF
+#endif
+
+#ifndef KVM_CPUID_SIGNATURE_NEXT
+#define KVM_CPUID_SIGNATURE_NEXT                0x40000100
+#endif
+
+void hyperv_enable_vapic_recommended(bool val);
+void hyperv_enable_relaxed_timing(bool val);
+void hyperv_set_spinlock_retries(int val);
+
+bool hyperv_enabled(void);
+bool hyperv_hypercall_available(void);
+bool hyperv_vapic_recommended(void);
+bool hyperv_relaxed_timing_enabled(void);
+int hyperv_get_spinlock_retries(void);
+
+#endif /* QEMU_HW_HYPERV_H */
-- 
1.7.4.4

[Qemu-devel] [PATCH 2/2] [PATCH RFC v2 2/2] hyper-v: initialize Hyper-V CPUID leaves.

[Vadim Rozenfeld]

---
 target-i386/kvm.c |   73 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 71 insertions(+), 2 deletions(-)

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 82fec8c..c061e3b 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -29,6 +29,7 @@
 #include "hw/pc.h"
 #include "hw/apic.h"
 #include "ioport.h"
+#include "hyperv.h"
 
 //#define DEBUG_KVM
 
@@ -380,11 +381,16 @@ int kvm_arch_init_vcpu(CPUState *env)
     cpuid_i = 0;
 
     /* Paravirtualization CPUIDs */
-    memcpy(signature, "KVMKVMKVM\0\0\0", 12);
     c = &cpuid_data.entries[cpuid_i++];
     memset(c, 0, sizeof(*c));
     c->function = KVM_CPUID_SIGNATURE;
-    c->eax = 0;
+    if (!hyperv_enabled()) {
+        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
+        c->eax = 0;
+    } else {
+        memcpy(signature, "Microsoft Hv", 12);
+        c->eax = HYPERV_CPUID_MIN;
+    }
     c->ebx = signature[0];
     c->ecx = signature[1];
     c->edx = signature[2];
@@ -395,6 +401,54 @@ int kvm_arch_init_vcpu(CPUState *env)
     c->eax = env->cpuid_kvm_features &
         kvm_arch_get_supported_cpuid(s, KVM_CPUID_FEATURES, 0, R_EAX);
 
+    if (hyperv_enabled()) {
+        memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
+        c->eax = signature[0];
+
+        c = &cpuid_data.entries[cpuid_i++];
+        memset(c, 0, sizeof(*c));
+        c->function = HYPERV_CPUID_VERSION;
+        c->eax = 0x00001bbc;
+        c->ebx = 0x00060001;
+
+        c = &cpuid_data.entries[cpuid_i++];
+        memset(c, 0, sizeof(*c));
+        c->function = HYPERV_CPUID_FEATURES;
+        if (hyperv_relaxed_timing_enabled()) {
+            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
+        }
+        if (hyperv_vapic_recommended()) {
+            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
+            c->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
+        }
+
+        c = &cpuid_data.entries[cpuid_i++];
+        memset(c, 0, sizeof(*c));
+        c->function = HYPERV_CPUID_ENLIGHTMENT_INFO;
+        if (hyperv_relaxed_timing_enabled()) {
+            c->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
+        }
+        if (hyperv_vapic_recommended()) {
+            c->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
+        }
+        c->ebx = hyperv_get_spinlock_retries();
+
+        c = &cpuid_data.entries[cpuid_i++];
+        memset(c, 0, sizeof(*c));
+        c->function = HYPERV_CPUID_IMPLEMENT_LIMITS;
+        c->eax = 0x40;
+        c->ebx = 0x40;
+
+        c = &cpuid_data.entries[cpuid_i++];
+        memset(c, 0, sizeof(*c));
+        c->function = KVM_CPUID_SIGNATURE_NEXT;
+        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
+        c->eax = 0;
+        c->ebx = signature[0];
+        c->ecx = signature[1];
+        c->edx = signature[2];
+    }
+
     has_msr_async_pf_en = c->eax & (1 << KVM_FEATURE_ASYNC_PF);
 
     cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);
@@ -953,6 +1007,13 @@ static int kvm_put_msrs(CPUState *env, int level)
             kvm_msr_entry_set(&msrs[n++], MSR_KVM_ASYNC_PF_EN,
                               env->async_pf_en_msr);
         }
+        if (hyperv_hypercall_available()) {
+            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_GUEST_OS_ID, 0);
+            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_HYPERCALL, 0);
+        }
+        if (hyperv_vapic_recommended()) {
+            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_APIC_ASSIST_PAGE, 0);
+        }
     }
     if (env->mcg_cap) {
         int i;
@@ -1190,6 +1251,14 @@ static int kvm_get_msrs(CPUState *env)
         msrs[n++].index = MSR_KVM_ASYNC_PF_EN;
     }
 
+    if (hyperv_hypercall_available()) {
+        msrs[n++].index = HV_X64_MSR_GUEST_OS_ID;
+        msrs[n++].index = HV_X64_MSR_HYPERCALL;
+    }
+    if (hyperv_vapic_recommended()) {
+        msrs[n++].index = HV_X64_MSR_APIC_ASSIST_PAGE;
+    }
+
     if (env->mcg_cap) {
         msrs[n++].index = MSR_MCG_STATUS;
         msrs[n++].index = MSR_MCG_CTL;
-- 
1.7.4.4

Re: [Qemu-devel] [PATCH RFC v2 0/2] Initial support for Microsoft Hyper-V.

[Marcelo Tosatti]

On Sun, Oct 23, 2011 at 05:39:47PM +0200, Vadim Rozenfeld wrote:
> With the following series of patches we are starting to implement
> some basic Microsoft Hyper-V Enlightenment functionality. This series
> is mostly about adding support for relaxed timing, spinlock,
> and virtual apic.
> 
> For more Hyper-V related information please see:
> "Hypervisor Functional Specification v2.0: For Windows Server 2008 R2" at
> http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=18673
> 
> Changelog:
>  v2->v1
>   - remove KVM_CAP_IRQCHIP ifdef,
>   - remove CONFIG_HYPERV config option,
>   - move KVM leaves to new location (0x40000100),
>   - cosmetic changes.
>  v0->v1
>   - move hyper-v parameters under cpu category,
>   - move hyper-v stuff to target-i386 directory,
>   - make CONFIG_HYPERV enabled by default for
>     i386-softmmu and x86_64-softmmu configurations,
>   - rearrange the patches from v0,
>   - set HV_X64_MSR_HYPERCALL, HV_X64_MSR_GUEST_OS_ID,
>     and HV_X64_MSR_APIC_ASSIST_PAGE to 0 on system reset.

Paolo, Jan, can you ack please? 

IMO making it TCG-friendly is nice, but, can be done later.

Re: [Qemu-devel] [PATCH 1/2] [PATCH RFC v2 1/2] hyper-v: introduce Hyper-V support infrastructure.

[Jan Kiszka]

On 2011-10-23 17:39, Vadim Rozenfeld wrote:
> ---
>  Makefile.target      |    2 +
>  target-i386/cpuid.c  |   14 ++++++++++
>  target-i386/hyperv.c |   65 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  target-i386/hyperv.h |   37 ++++++++++++++++++++++++++++
>  4 files changed, 118 insertions(+), 0 deletions(-)
>  create mode 100644 target-i386/hyperv.c
>  create mode 100644 target-i386/hyperv.h
> 
> diff --git a/Makefile.target b/Makefile.target
> index 325f26e..446fabc 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -202,6 +202,8 @@ obj-$(CONFIG_NO_KVM) += kvm-stub.o
>  obj-y += memory.o
>  LIBS+=-lz
>  
> +obj-i386-y +=hyperv.o
> +
>  QEMU_CFLAGS += $(VNC_TLS_CFLAGS)
>  QEMU_CFLAGS += $(VNC_SASL_CFLAGS)
>  QEMU_CFLAGS += $(VNC_JPEG_CFLAGS)
> diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
> index 1e8bcff..261c168 100644
> --- a/target-i386/cpuid.c
> +++ b/target-i386/cpuid.c
> @@ -27,6 +27,8 @@
>  #include "qemu-option.h"
>  #include "qemu-config.h"
>  
> +#include "hyperv.h"
> +
>  /* feature flags taken from "Intel Processor Identification and the CPUID
>   * Instruction" and AMD's "CPUID Specification".  In cases of disagreement
>   * between feature naming conventions, aliases may be added.
> @@ -716,6 +718,14 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
>                      goto error;
>                  }
>                  x86_cpu_def->tsc_khz = tsc_freq / 1000;
> +            } else if (!strcmp(featurestr, "hv_spinlocks")) {
> +               char *err;
> +               numvalue = strtoul(val, &err, 0);
> +               if (!*val || *err) {

Indention is off here.

> +                    fprintf(stderr, "bad numerical value %s\n", val);
> +                    goto error;
> +                }
> +                hyperv_set_spinlock_retries(numvalue);
>              } else {
>                  fprintf(stderr, "unrecognized feature %s\n", featurestr);
>                  goto error;
> @@ -724,6 +734,10 @@ static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)
>              check_cpuid = 1;
>          } else if (!strcmp(featurestr, "enforce")) {
>              check_cpuid = enforce_cpuid = 1;
> +        } else if (!strcmp(featurestr, "hv_relaxed")) {
> +            hyperv_enable_relaxed_timing(true);
> +        } else if (!strcmp(featurestr, "hv_vapic")) {
> +            hyperv_enable_vapic_recommended(true);            
>          } else {
>              fprintf(stderr, "feature string `%s' not in format (+feature|-feature|feature=xyz)\n", featurestr);
>              goto error;
> diff --git a/target-i386/hyperv.c b/target-i386/hyperv.c
> new file mode 100644
> index 0000000..b2e57ad
> --- /dev/null
> +++ b/target-i386/hyperv.c
> @@ -0,0 +1,65 @@
> +/*
> + * QEMU Hyper-V support
> + *
> + * Copyright Red Hat, Inc. 2011
> + *
> + * Author: Vadim Rozenfeld     <vrozenfe@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include "hyperv.h"
> +
> +static bool hyperv_vapic;
> +static bool hyperv_relaxed_timing;
> +static int hyperv_spinlock_attempts = HYPERV_SPINLOCK_NEVER_RETRY;
> +
> +void hyperv_enable_vapic_recommended(bool val)
> +{
> +    hyperv_vapic = val;
> +}
> +
> +void hyperv_enable_relaxed_timing(bool val)
> +{
> +    hyperv_relaxed_timing = val;
> +}
> +
> +void hyperv_set_spinlock_retries(int val)
> +{
> +    hyperv_spinlock_attempts = val;
> +    if (hyperv_spinlock_attempts < 0xFFF) {
> +        hyperv_spinlock_attempts = 0xFFF;
> +    }
> +}
> +
> +bool hyperv_enabled(void)
> +{
> +    return hyperv_hypercall_available() || hyperv_relaxed_timing_enabled();
> +}
> +
> +bool hyperv_hypercall_available(void)
> +{
> +    if (hyperv_vapic ||
> +        (hyperv_spinlock_attempts != HYPERV_SPINLOCK_NEVER_RETRY)) {

[ minor: braces arount the second condition aren't needed. ]

> +      return true;
> +    }
> +    return false;
> +}
> +
> +bool hyperv_vapic_recommended(void)
> +{
> +    return hyperv_vapic;
> +}
> +
> +bool hyperv_relaxed_timing_enabled(void)
> +{
> +    return hyperv_relaxed_timing;
> +}
> +
> +int hyperv_get_spinlock_retries(void)
> +{
> +    return hyperv_spinlock_attempts;
> +}
> +
> diff --git a/target-i386/hyperv.h b/target-i386/hyperv.h
> new file mode 100644
> index 0000000..0d742f8
> --- /dev/null
> +++ b/target-i386/hyperv.h
> @@ -0,0 +1,37 @@
> +/*
> + * QEMU Hyper-V support
> + *
> + * Copyright Red Hat, Inc. 2011
> + *
> + * Author: Vadim Rozenfeld     <vrozenfe@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#ifndef QEMU_HW_HYPERV_H
> +#define QEMU_HW_HYPERV_H 1
> +
> +#include "qemu-common.h"
> +#include <asm/hyperv.h>
> +
> +#ifndef HYPERV_SPINLOCK_NEVER_RETRY
> +#define HYPERV_SPINLOCK_NEVER_RETRY             0xFFFFFFFF
> +#endif
> +
> +#ifndef KVM_CPUID_SIGNATURE_NEXT
> +#define KVM_CPUID_SIGNATURE_NEXT                0x40000100
> +#endif
> +
> +void hyperv_enable_vapic_recommended(bool val);
> +void hyperv_enable_relaxed_timing(bool val);
> +void hyperv_set_spinlock_retries(int val);
> +
> +bool hyperv_enabled(void);
> +bool hyperv_hypercall_available(void);
> +bool hyperv_vapic_recommended(void);
> +bool hyperv_relaxed_timing_enabled(void);
> +int hyperv_get_spinlock_retries(void);
> +
> +#endif /* QEMU_HW_HYPERV_H */

Looks good to me otherwise.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux

Re: [Qemu-devel] [PATCH 2/2] [PATCH RFC v2 2/2] hyper-v: initialize Hyper-V CPUID leaves.

[Jan Kiszka]

On 2011-10-23 17:39, Vadim Rozenfeld wrote:
> ---
>  target-i386/kvm.c |   73 +++++++++++++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 71 insertions(+), 2 deletions(-)
> 
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 82fec8c..c061e3b 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -29,6 +29,7 @@
>  #include "hw/pc.h"
>  #include "hw/apic.h"
>  #include "ioport.h"
> +#include "hyperv.h"
>  
>  //#define DEBUG_KVM
>  
> @@ -380,11 +381,16 @@ int kvm_arch_init_vcpu(CPUState *env)
>      cpuid_i = 0;
>  
>      /* Paravirtualization CPUIDs */
> -    memcpy(signature, "KVMKVMKVM\0\0\0", 12);
>      c = &cpuid_data.entries[cpuid_i++];
>      memset(c, 0, sizeof(*c));
>      c->function = KVM_CPUID_SIGNATURE;
> -    c->eax = 0;
> +    if (!hyperv_enabled()) {
> +        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> +        c->eax = 0;
> +    } else {
> +        memcpy(signature, "Microsoft Hv", 12);
> +        c->eax = HYPERV_CPUID_MIN;
> +    }
>      c->ebx = signature[0];
>      c->ecx = signature[1];
>      c->edx = signature[2];
> @@ -395,6 +401,54 @@ int kvm_arch_init_vcpu(CPUState *env)
>      c->eax = env->cpuid_kvm_features &
>          kvm_arch_get_supported_cpuid(s, KVM_CPUID_FEATURES, 0, R_EAX);
>  
> +    if (hyperv_enabled()) {
> +        memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
> +        c->eax = signature[0];
> +
> +        c = &cpuid_data.entries[cpuid_i++];
> +        memset(c, 0, sizeof(*c));
> +        c->function = HYPERV_CPUID_VERSION;
> +        c->eax = 0x00001bbc;
> +        c->ebx = 0x00060001;
> +
> +        c = &cpuid_data.entries[cpuid_i++];
> +        memset(c, 0, sizeof(*c));
> +        c->function = HYPERV_CPUID_FEATURES;
> +        if (hyperv_relaxed_timing_enabled()) {
> +            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> +        }
> +        if (hyperv_vapic_recommended()) {
> +            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> +            c->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
> +        }
> +
> +        c = &cpuid_data.entries[cpuid_i++];
> +        memset(c, 0, sizeof(*c));
> +        c->function = HYPERV_CPUID_ENLIGHTMENT_INFO;
> +        if (hyperv_relaxed_timing_enabled()) {
> +            c->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
> +        }
> +        if (hyperv_vapic_recommended()) {
> +            c->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
> +        }
> +        c->ebx = hyperv_get_spinlock_retries();
> +
> +        c = &cpuid_data.entries[cpuid_i++];
> +        memset(c, 0, sizeof(*c));
> +        c->function = HYPERV_CPUID_IMPLEMENT_LIMITS;
> +        c->eax = 0x40;
> +        c->ebx = 0x40;
> +
> +        c = &cpuid_data.entries[cpuid_i++];
> +        memset(c, 0, sizeof(*c));
> +        c->function = KVM_CPUID_SIGNATURE_NEXT;
> +        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> +        c->eax = 0;
> +        c->ebx = signature[0];
> +        c->ecx = signature[1];
> +        c->edx = signature[2];
> +    }
> +
>      has_msr_async_pf_en = c->eax & (1 << KVM_FEATURE_ASYNC_PF);
>  
>      cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);
> @@ -953,6 +1007,13 @@ static int kvm_put_msrs(CPUState *env, int level)
>              kvm_msr_entry_set(&msrs[n++], MSR_KVM_ASYNC_PF_EN,
>                                env->async_pf_en_msr);
>          }
> +        if (hyperv_hypercall_available()) {
> +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_GUEST_OS_ID, 0);
> +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_HYPERCALL, 0);
> +        }
> +        if (hyperv_vapic_recommended()) {
> +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_APIC_ASSIST_PAGE, 0);
> +        }
>      }
>      if (env->mcg_cap) {
>          int i;
> @@ -1190,6 +1251,14 @@ static int kvm_get_msrs(CPUState *env)
>          msrs[n++].index = MSR_KVM_ASYNC_PF_EN;
>      }
>  
> +    if (hyperv_hypercall_available()) {
> +        msrs[n++].index = HV_X64_MSR_GUEST_OS_ID;
> +        msrs[n++].index = HV_X64_MSR_HYPERCALL;
> +    }
> +    if (hyperv_vapic_recommended()) {
> +        msrs[n++].index = HV_X64_MSR_APIC_ASSIST_PAGE;
> +    }
> +
>      if (env->mcg_cap) {
>          msrs[n++].index = MSR_MCG_STATUS;
>          msrs[n++].index = MSR_MCG_CTL;

Not sure if we discussed this already: Is there no need to save/restore
the HV MSR values in the vcpu structure? Specifcially kvm_get_msrs looks
fishy as you request to read the state from the kernel but then simply
ignore it.

Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux

Re: [Qemu-devel] [PATCH 2/2] [PATCH RFC v2 2/2] hyper-v: initialize Hyper-V CPUID leaves.

[Vadim Rozenfeld]

On Thu, 2011-12-01 at 15:52 +0100, Jan Kiszka wrote:
> On 2011-10-23 17:39, Vadim Rozenfeld wrote:
> > ---
> >  target-i386/kvm.c |   73 +++++++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 files changed, 71 insertions(+), 2 deletions(-)
> > 
> > diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> > index 82fec8c..c061e3b 100644
> > --- a/target-i386/kvm.c
> > +++ b/target-i386/kvm.c
> > @@ -29,6 +29,7 @@
> >  #include "hw/pc.h"
> >  #include "hw/apic.h"
> >  #include "ioport.h"
> > +#include "hyperv.h"
> >  
> >  //#define DEBUG_KVM
> >  
> > @@ -380,11 +381,16 @@ int kvm_arch_init_vcpu(CPUState *env)
> >      cpuid_i = 0;
> >  
> >      /* Paravirtualization CPUIDs */
> > -    memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> >      c = &cpuid_data.entries[cpuid_i++];
> >      memset(c, 0, sizeof(*c));
> >      c->function = KVM_CPUID_SIGNATURE;
> > -    c->eax = 0;
> > +    if (!hyperv_enabled()) {
> > +        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> > +        c->eax = 0;
> > +    } else {
> > +        memcpy(signature, "Microsoft Hv", 12);
> > +        c->eax = HYPERV_CPUID_MIN;
> > +    }
> >      c->ebx = signature[0];
> >      c->ecx = signature[1];
> >      c->edx = signature[2];
> > @@ -395,6 +401,54 @@ int kvm_arch_init_vcpu(CPUState *env)
> >      c->eax = env->cpuid_kvm_features &
> >          kvm_arch_get_supported_cpuid(s, KVM_CPUID_FEATURES, 0, R_EAX);
> >  
> > +    if (hyperv_enabled()) {
> > +        memcpy(signature, "Hv#1\0\0\0\0\0\0\0\0", 12);
> > +        c->eax = signature[0];
> > +
> > +        c = &cpuid_data.entries[cpuid_i++];
> > +        memset(c, 0, sizeof(*c));
> > +        c->function = HYPERV_CPUID_VERSION;
> > +        c->eax = 0x00001bbc;
> > +        c->ebx = 0x00060001;
> > +
> > +        c = &cpuid_data.entries[cpuid_i++];
> > +        memset(c, 0, sizeof(*c));
> > +        c->function = HYPERV_CPUID_FEATURES;
> > +        if (hyperv_relaxed_timing_enabled()) {
> > +            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> > +        }
> > +        if (hyperv_vapic_recommended()) {
> > +            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> > +            c->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
> > +        }
> > +
> > +        c = &cpuid_data.entries[cpuid_i++];
> > +        memset(c, 0, sizeof(*c));
> > +        c->function = HYPERV_CPUID_ENLIGHTMENT_INFO;
> > +        if (hyperv_relaxed_timing_enabled()) {
> > +            c->eax |= HV_X64_RELAXED_TIMING_RECOMMENDED;
> > +        }
> > +        if (hyperv_vapic_recommended()) {
> > +            c->eax |= HV_X64_APIC_ACCESS_RECOMMENDED;
> > +        }
> > +        c->ebx = hyperv_get_spinlock_retries();
> > +
> > +        c = &cpuid_data.entries[cpuid_i++];
> > +        memset(c, 0, sizeof(*c));
> > +        c->function = HYPERV_CPUID_IMPLEMENT_LIMITS;
> > +        c->eax = 0x40;
> > +        c->ebx = 0x40;
> > +
> > +        c = &cpuid_data.entries[cpuid_i++];
> > +        memset(c, 0, sizeof(*c));
> > +        c->function = KVM_CPUID_SIGNATURE_NEXT;
> > +        memcpy(signature, "KVMKVMKVM\0\0\0", 12);
> > +        c->eax = 0;
> > +        c->ebx = signature[0];
> > +        c->ecx = signature[1];
> > +        c->edx = signature[2];
> > +    }
> > +
> >      has_msr_async_pf_en = c->eax & (1 << KVM_FEATURE_ASYNC_PF);
> >  
> >      cpu_x86_cpuid(env, 0, 0, &limit, &unused, &unused, &unused);
> > @@ -953,6 +1007,13 @@ static int kvm_put_msrs(CPUState *env, int level)
> >              kvm_msr_entry_set(&msrs[n++], MSR_KVM_ASYNC_PF_EN,
> >                                env->async_pf_en_msr);
> >          }
> > +        if (hyperv_hypercall_available()) {
> > +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_GUEST_OS_ID, 0);
> > +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_HYPERCALL, 0);
> > +        }
> > +        if (hyperv_vapic_recommended()) {
> > +            kvm_msr_entry_set(&msrs[n++], HV_X64_MSR_APIC_ASSIST_PAGE, 0);
> > +        }
> >      }
> >      if (env->mcg_cap) {
> >          int i;
> > @@ -1190,6 +1251,14 @@ static int kvm_get_msrs(CPUState *env)
> >          msrs[n++].index = MSR_KVM_ASYNC_PF_EN;
> >      }
> >  
> > +    if (hyperv_hypercall_available()) {
> > +        msrs[n++].index = HV_X64_MSR_GUEST_OS_ID;
> > +        msrs[n++].index = HV_X64_MSR_HYPERCALL;
> > +    }
> > +    if (hyperv_vapic_recommended()) {
> > +        msrs[n++].index = HV_X64_MSR_APIC_ASSIST_PAGE;
> > +    }
> > +
> >      if (env->mcg_cap) {
> >          msrs[n++].index = MSR_MCG_STATUS;
> >          msrs[n++].index = MSR_MCG_CTL;
> 
> Not sure if we discussed this already: Is there no need to save/restore
> the HV MSR values in the vcpu structure? Specifcially kvm_get_msrs looks
> fishy as you request to read the state from the kernel but then simply
> ignore it.

You're right. We don't need to keep hyper-v msrs in the vcpu structure
at the moment. I will revert kvm_get_msrs changes back to the original
state.
Vadim. 
> 
> Jan
>