Enabling Hyper-V emulation for a Windows VM is a tiring experience as it
requires listing all currently supported enlightenments ("hv_*" CPU
features) explicitly. We do have a 'hv_passthrough' mode enabling
everything but it can't be used in production as it prevents migration.
Introduce a simple 'hyperv=on' option for all x86 machine types enabling
all currently supported Hyper-V enlightenments. Later, when new
enlightenments get implemented, we will be adding them to newer machine
types only (by disabling them for legacy machine types) thus preserving
migration.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
docs/hyperv.txt | 8 ++++++++
hw/i386/x86.c | 30 ++++++++++++++++++++++++++++++
include/hw/i386/x86.h | 7 +++++++
target/i386/cpu.c | 14 ++++++++++++++
4 files changed, 59 insertions(+)
diff --git a/docs/hyperv.txt b/docs/hyperv.txt
index 5df00da54fc4..1a76a07f8417 100644
--- a/docs/hyperv.txt
+++ b/docs/hyperv.txt
@@ -29,6 +29,14 @@ When any set of the Hyper-V enlightenments is enabled, QEMU changes hypervisor
identification (CPUID 0x40000000..0x4000000A) to Hyper-V. KVM identification
and features are kept in leaves 0x40000100..0x40000101.
+Hyper-V enlightenments can be enabled in bulk by specifying 'hyperv=on' to an
+x86 machine type:
+
+ qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split,hyperv=on ...
+
+Note, new enlightenments are only added to the latest (in-develompent) machine
+type, older machine types keep the list of the supported features intact to
+safeguard migration.
3. Existing enlightenments
===========================
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 3137a2008588..eeecd4e3322f 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -1171,6 +1171,20 @@ static void x86_machine_set_acpi(Object *obj, Visitor *v, const char *name,
visit_type_OnOffAuto(v, name, &x86ms->acpi, errp);
}
+static bool x86_machine_get_hyperv(Object *obj, Error **errp)
+{
+ X86MachineState *x86ms = X86_MACHINE(obj);
+
+ return x86ms->hyperv_enabled;
+}
+
+static void x86_machine_set_hyperv(Object *obj, bool value, Error **errp)
+{
+ X86MachineState *x86ms = X86_MACHINE(obj);
+
+ x86ms->hyperv_enabled = value;
+}
+
static void x86_machine_initfn(Object *obj)
{
X86MachineState *x86ms = X86_MACHINE(obj);
@@ -1193,6 +1207,16 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
x86mc->save_tsc_khz = true;
nc->nmi_monitor_handler = x86_nmi;
+ /* Hyper-V features enabled with 'hyperv=on' */
+ x86mc->hyperv_features = BIT(HYPERV_FEAT_RELAXED) | BIT(HYPERV_FEAT_VAPIC) |
+ BIT(HYPERV_FEAT_TIME) | BIT(HYPERV_FEAT_CRASH) |
+ BIT(HYPERV_FEAT_RESET) | BIT(HYPERV_FEAT_VPINDEX) |
+ BIT(HYPERV_FEAT_RUNTIME) | BIT(HYPERV_FEAT_SYNIC) |
+ BIT(HYPERV_FEAT_STIMER) | BIT(HYPERV_FEAT_FREQUENCIES) |
+ BIT(HYPERV_FEAT_REENLIGHTENMENT) | BIT(HYPERV_FEAT_TLBFLUSH) |
+ BIT(HYPERV_FEAT_EVMCS) | BIT(HYPERV_FEAT_IPI) |
+ BIT(HYPERV_FEAT_STIMER_DIRECT);
+
object_class_property_add(oc, X86_MACHINE_SMM, "OnOffAuto",
x86_machine_get_smm, x86_machine_set_smm,
NULL, NULL);
@@ -1204,6 +1228,12 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
NULL, NULL);
object_class_property_set_description(oc, X86_MACHINE_ACPI,
"Enable ACPI");
+
+ object_class_property_add_bool(oc, X86_MACHINE_HYPERV,
+ x86_machine_get_hyperv, x86_machine_set_hyperv);
+
+ object_class_property_set_description(oc, X86_MACHINE_HYPERV,
+ "Enable Hyper-V enlightenments");
}
static const TypeInfo x86_machine_info = {
diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
index d5dcf7a07fdc..2b989e5fc49d 100644
--- a/include/hw/i386/x86.h
+++ b/include/hw/i386/x86.h
@@ -38,6 +38,9 @@ struct X86MachineClass {
bool save_tsc_khz;
/* Enables contiguous-apic-ID mode */
bool compat_apic_id_mode;
+
+ /* Hyper-V features enabled with 'hyperv=on' */
+ uint64_t hyperv_features;
};
struct X86MachineState {
@@ -70,10 +73,14 @@ struct X86MachineState {
* will be translated to MSI messages in the address space.
*/
AddressSpace *ioapic_as;
+
+ /* Hyper-V emulation */
+ bool hyperv_enabled;
};
#define X86_MACHINE_SMM "smm"
#define X86_MACHINE_ACPI "acpi"
+#define X86_MACHINE_HYPERV "hyperv"
#define TYPE_X86_MACHINE MACHINE_TYPE_NAME("x86")
OBJECT_DECLARE_TYPE(X86MachineState, X86MachineClass, X86_MACHINE)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 55706c8050fe..d0961c1838ad 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -53,6 +53,7 @@
#include "sysemu/tcg.h"
#include "hw/qdev-properties.h"
#include "hw/i386/topology.h"
+#include "hw/i386/x86.h"
#ifndef CONFIG_USER_ONLY
#include "exec/address-spaces.h"
#include "hw/i386/apic_internal.h"
@@ -6409,8 +6410,21 @@ static void x86_cpu_filter_features(X86CPU *cpu, bool verbose)
static void x86_cpu_hyperv_realize(X86CPU *cpu)
{
+ X86MachineState *x86ms = X86_MACHINE(qdev_get_machine());
+ X86MachineClass *x86mc = X86_MACHINE_GET_CLASS(x86ms);
+ uint64_t feat;
size_t len;
+ if (x86ms->hyperv_enabled) {
+ feat = x86mc->hyperv_features;
+ /* Enlightened VMCS is only available on Intel/VMX */
+ if (!cpu_has_vmx(&cpu->env)) {
+ feat &= ~BIT(HYPERV_FEAT_EVMCS);
+ }
+
+ cpu->hyperv_features |= feat;
+ }
+
/* Hyper-V vendor id */
if (!cpu->hyperv_vendor) {
object_property_set_str(OBJECT(cpu), "hv-vendor-id", "Microsoft Hv",
--
2.25.4
On Fri, Oct 09, 2020 at 02:18:42PM +0200, Vitaly Kuznetsov wrote:
> Enabling Hyper-V emulation for a Windows VM is a tiring experience as it
> requires listing all currently supported enlightenments ("hv_*" CPU
> features) explicitly. We do have a 'hv_passthrough' mode enabling
> everything but it can't be used in production as it prevents migration.
>
> Introduce a simple 'hyperv=on' option for all x86 machine types enabling
> all currently supported Hyper-V enlightenments. Later, when new
> enlightenments get implemented, we will be adding them to newer machine
> types only (by disabling them for legacy machine types) thus preserving
> migration.
>
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
This patch seems to be especially useful, and I wonder if we
could make sure this is included before all the rest of the
series. Especially considering that the KVM changes might take a
while to be merged.
Would you be able to submit this independently from the rest of
the series? You can add my:
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
My only (minor) suggestion is to rename
X86MachineClass.hyperv_features to
X86MachineClass.default_hyperv_features.
> ---
> docs/hyperv.txt | 8 ++++++++
> hw/i386/x86.c | 30 ++++++++++++++++++++++++++++++
> include/hw/i386/x86.h | 7 +++++++
> target/i386/cpu.c | 14 ++++++++++++++
> 4 files changed, 59 insertions(+)
>
> diff --git a/docs/hyperv.txt b/docs/hyperv.txt
> index 5df00da54fc4..1a76a07f8417 100644
> --- a/docs/hyperv.txt
> +++ b/docs/hyperv.txt
> @@ -29,6 +29,14 @@ When any set of the Hyper-V enlightenments is enabled, QEMU changes hypervisor
> identification (CPUID 0x40000000..0x4000000A) to Hyper-V. KVM identification
> and features are kept in leaves 0x40000100..0x40000101.
>
> +Hyper-V enlightenments can be enabled in bulk by specifying 'hyperv=on' to an
> +x86 machine type:
> +
> + qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split,hyperv=on ...
> +
> +Note, new enlightenments are only added to the latest (in-develompent) machine
> +type, older machine types keep the list of the supported features intact to
> +safeguard migration.
>
> 3. Existing enlightenments
> ===========================
> diff --git a/hw/i386/x86.c b/hw/i386/x86.c
> index 3137a2008588..eeecd4e3322f 100644
> --- a/hw/i386/x86.c
> +++ b/hw/i386/x86.c
> @@ -1171,6 +1171,20 @@ static void x86_machine_set_acpi(Object *obj, Visitor *v, const char *name,
> visit_type_OnOffAuto(v, name, &x86ms->acpi, errp);
> }
>
> +static bool x86_machine_get_hyperv(Object *obj, Error **errp)
> +{
> + X86MachineState *x86ms = X86_MACHINE(obj);
> +
> + return x86ms->hyperv_enabled;
> +}
> +
> +static void x86_machine_set_hyperv(Object *obj, bool value, Error **errp)
> +{
> + X86MachineState *x86ms = X86_MACHINE(obj);
> +
> + x86ms->hyperv_enabled = value;
> +}
> +
> static void x86_machine_initfn(Object *obj)
> {
> X86MachineState *x86ms = X86_MACHINE(obj);
> @@ -1193,6 +1207,16 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
> x86mc->save_tsc_khz = true;
> nc->nmi_monitor_handler = x86_nmi;
>
> + /* Hyper-V features enabled with 'hyperv=on' */
> + x86mc->hyperv_features = BIT(HYPERV_FEAT_RELAXED) | BIT(HYPERV_FEAT_VAPIC) |
> + BIT(HYPERV_FEAT_TIME) | BIT(HYPERV_FEAT_CRASH) |
> + BIT(HYPERV_FEAT_RESET) | BIT(HYPERV_FEAT_VPINDEX) |
> + BIT(HYPERV_FEAT_RUNTIME) | BIT(HYPERV_FEAT_SYNIC) |
> + BIT(HYPERV_FEAT_STIMER) | BIT(HYPERV_FEAT_FREQUENCIES) |
> + BIT(HYPERV_FEAT_REENLIGHTENMENT) | BIT(HYPERV_FEAT_TLBFLUSH) |
> + BIT(HYPERV_FEAT_EVMCS) | BIT(HYPERV_FEAT_IPI) |
> + BIT(HYPERV_FEAT_STIMER_DIRECT);
> +
> object_class_property_add(oc, X86_MACHINE_SMM, "OnOffAuto",
> x86_machine_get_smm, x86_machine_set_smm,
> NULL, NULL);
> @@ -1204,6 +1228,12 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
> NULL, NULL);
> object_class_property_set_description(oc, X86_MACHINE_ACPI,
> "Enable ACPI");
> +
> + object_class_property_add_bool(oc, X86_MACHINE_HYPERV,
> + x86_machine_get_hyperv, x86_machine_set_hyperv);
> +
> + object_class_property_set_description(oc, X86_MACHINE_HYPERV,
> + "Enable Hyper-V enlightenments");
> }
>
> static const TypeInfo x86_machine_info = {
> diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
> index d5dcf7a07fdc..2b989e5fc49d 100644
> --- a/include/hw/i386/x86.h
> +++ b/include/hw/i386/x86.h
> @@ -38,6 +38,9 @@ struct X86MachineClass {
> bool save_tsc_khz;
> /* Enables contiguous-apic-ID mode */
> bool compat_apic_id_mode;
> +
> + /* Hyper-V features enabled with 'hyperv=on' */
> + uint64_t hyperv_features;
> };
>
> struct X86MachineState {
> @@ -70,10 +73,14 @@ struct X86MachineState {
> * will be translated to MSI messages in the address space.
> */
> AddressSpace *ioapic_as;
> +
> + /* Hyper-V emulation */
> + bool hyperv_enabled;
> };
>
> #define X86_MACHINE_SMM "smm"
> #define X86_MACHINE_ACPI "acpi"
> +#define X86_MACHINE_HYPERV "hyperv"
>
> #define TYPE_X86_MACHINE MACHINE_TYPE_NAME("x86")
> OBJECT_DECLARE_TYPE(X86MachineState, X86MachineClass, X86_MACHINE)
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 55706c8050fe..d0961c1838ad 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -53,6 +53,7 @@
> #include "sysemu/tcg.h"
> #include "hw/qdev-properties.h"
> #include "hw/i386/topology.h"
> +#include "hw/i386/x86.h"
> #ifndef CONFIG_USER_ONLY
> #include "exec/address-spaces.h"
> #include "hw/i386/apic_internal.h"
> @@ -6409,8 +6410,21 @@ static void x86_cpu_filter_features(X86CPU *cpu, bool verbose)
>
> static void x86_cpu_hyperv_realize(X86CPU *cpu)
> {
> + X86MachineState *x86ms = X86_MACHINE(qdev_get_machine());
> + X86MachineClass *x86mc = X86_MACHINE_GET_CLASS(x86ms);
> + uint64_t feat;
> size_t len;
>
> + if (x86ms->hyperv_enabled) {
> + feat = x86mc->hyperv_features;
> + /* Enlightened VMCS is only available on Intel/VMX */
> + if (!cpu_has_vmx(&cpu->env)) {
> + feat &= ~BIT(HYPERV_FEAT_EVMCS);
> + }
> +
> + cpu->hyperv_features |= feat;
> + }
> +
> /* Hyper-V vendor id */
> if (!cpu->hyperv_vendor) {
> object_property_set_str(OBJECT(cpu), "hv-vendor-id", "Microsoft Hv",
> --
> 2.25.4
>
--
Eduardo
Eduardo Habkost <ehabkost@redhat.com> writes:
> On Fri, Oct 09, 2020 at 02:18:42PM +0200, Vitaly Kuznetsov wrote:
>> Enabling Hyper-V emulation for a Windows VM is a tiring experience as it
>> requires listing all currently supported enlightenments ("hv_*" CPU
>> features) explicitly. We do have a 'hv_passthrough' mode enabling
>> everything but it can't be used in production as it prevents migration.
>>
>> Introduce a simple 'hyperv=on' option for all x86 machine types enabling
>> all currently supported Hyper-V enlightenments. Later, when new
>> enlightenments get implemented, we will be adding them to newer machine
>> types only (by disabling them for legacy machine types) thus preserving
>> migration.
>>
>> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
>
> This patch seems to be especially useful, and I wonder if we
> could make sure this is included before all the rest of the
> series. Especially considering that the KVM changes might take a
> while to be merged.
The required KVM changes are queued for 5.11 and I was delaying next
submission till then.
>
> Would you be able to submit this independently from the rest of
> the series? You can add my:
>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
>
> My only (minor) suggestion is to rename
> X86MachineClass.hyperv_features to
> X86MachineClass.default_hyperv_features.
Sure, will do. I'll probably pick a few small patches from the series
(e.g. the one bringing x86_cpu_hyperv_realize()) to minimize the code
churn in the future.
>
>> ---
>> docs/hyperv.txt | 8 ++++++++
>> hw/i386/x86.c | 30 ++++++++++++++++++++++++++++++
>> include/hw/i386/x86.h | 7 +++++++
>> target/i386/cpu.c | 14 ++++++++++++++
>> 4 files changed, 59 insertions(+)
>>
>> diff --git a/docs/hyperv.txt b/docs/hyperv.txt
>> index 5df00da54fc4..1a76a07f8417 100644
>> --- a/docs/hyperv.txt
>> +++ b/docs/hyperv.txt
>> @@ -29,6 +29,14 @@ When any set of the Hyper-V enlightenments is enabled, QEMU changes hypervisor
>> identification (CPUID 0x40000000..0x4000000A) to Hyper-V. KVM identification
>> and features are kept in leaves 0x40000100..0x40000101.
>>
>> +Hyper-V enlightenments can be enabled in bulk by specifying 'hyperv=on' to an
>> +x86 machine type:
>> +
>> + qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split,hyperv=on ...
>> +
>> +Note, new enlightenments are only added to the latest (in-develompent) machine
>> +type, older machine types keep the list of the supported features intact to
>> +safeguard migration.
>>
>> 3. Existing enlightenments
>> ===========================
>> diff --git a/hw/i386/x86.c b/hw/i386/x86.c
>> index 3137a2008588..eeecd4e3322f 100644
>> --- a/hw/i386/x86.c
>> +++ b/hw/i386/x86.c
>> @@ -1171,6 +1171,20 @@ static void x86_machine_set_acpi(Object *obj, Visitor *v, const char *name,
>> visit_type_OnOffAuto(v, name, &x86ms->acpi, errp);
>> }
>>
>> +static bool x86_machine_get_hyperv(Object *obj, Error **errp)
>> +{
>> + X86MachineState *x86ms = X86_MACHINE(obj);
>> +
>> + return x86ms->hyperv_enabled;
>> +}
>> +
>> +static void x86_machine_set_hyperv(Object *obj, bool value, Error **errp)
>> +{
>> + X86MachineState *x86ms = X86_MACHINE(obj);
>> +
>> + x86ms->hyperv_enabled = value;
>> +}
>> +
>> static void x86_machine_initfn(Object *obj)
>> {
>> X86MachineState *x86ms = X86_MACHINE(obj);
>> @@ -1193,6 +1207,16 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
>> x86mc->save_tsc_khz = true;
>> nc->nmi_monitor_handler = x86_nmi;
>>
>> + /* Hyper-V features enabled with 'hyperv=on' */
>> + x86mc->hyperv_features = BIT(HYPERV_FEAT_RELAXED) | BIT(HYPERV_FEAT_VAPIC) |
>> + BIT(HYPERV_FEAT_TIME) | BIT(HYPERV_FEAT_CRASH) |
>> + BIT(HYPERV_FEAT_RESET) | BIT(HYPERV_FEAT_VPINDEX) |
>> + BIT(HYPERV_FEAT_RUNTIME) | BIT(HYPERV_FEAT_SYNIC) |
>> + BIT(HYPERV_FEAT_STIMER) | BIT(HYPERV_FEAT_FREQUENCIES) |
>> + BIT(HYPERV_FEAT_REENLIGHTENMENT) | BIT(HYPERV_FEAT_TLBFLUSH) |
>> + BIT(HYPERV_FEAT_EVMCS) | BIT(HYPERV_FEAT_IPI) |
>> + BIT(HYPERV_FEAT_STIMER_DIRECT);
>> +
>> object_class_property_add(oc, X86_MACHINE_SMM, "OnOffAuto",
>> x86_machine_get_smm, x86_machine_set_smm,
>> NULL, NULL);
>> @@ -1204,6 +1228,12 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
>> NULL, NULL);
>> object_class_property_set_description(oc, X86_MACHINE_ACPI,
>> "Enable ACPI");
>> +
>> + object_class_property_add_bool(oc, X86_MACHINE_HYPERV,
>> + x86_machine_get_hyperv, x86_machine_set_hyperv);
>> +
>> + object_class_property_set_description(oc, X86_MACHINE_HYPERV,
>> + "Enable Hyper-V enlightenments");
>> }
>>
>> static const TypeInfo x86_machine_info = {
>> diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
>> index d5dcf7a07fdc..2b989e5fc49d 100644
>> --- a/include/hw/i386/x86.h
>> +++ b/include/hw/i386/x86.h
>> @@ -38,6 +38,9 @@ struct X86MachineClass {
>> bool save_tsc_khz;
>> /* Enables contiguous-apic-ID mode */
>> bool compat_apic_id_mode;
>> +
>> + /* Hyper-V features enabled with 'hyperv=on' */
>> + uint64_t hyperv_features;
>> };
>>
>> struct X86MachineState {
>> @@ -70,10 +73,14 @@ struct X86MachineState {
>> * will be translated to MSI messages in the address space.
>> */
>> AddressSpace *ioapic_as;
>> +
>> + /* Hyper-V emulation */
>> + bool hyperv_enabled;
>> };
>>
>> #define X86_MACHINE_SMM "smm"
>> #define X86_MACHINE_ACPI "acpi"
>> +#define X86_MACHINE_HYPERV "hyperv"
>>
>> #define TYPE_X86_MACHINE MACHINE_TYPE_NAME("x86")
>> OBJECT_DECLARE_TYPE(X86MachineState, X86MachineClass, X86_MACHINE)
>> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
>> index 55706c8050fe..d0961c1838ad 100644
>> --- a/target/i386/cpu.c
>> +++ b/target/i386/cpu.c
>> @@ -53,6 +53,7 @@
>> #include "sysemu/tcg.h"
>> #include "hw/qdev-properties.h"
>> #include "hw/i386/topology.h"
>> +#include "hw/i386/x86.h"
>> #ifndef CONFIG_USER_ONLY
>> #include "exec/address-spaces.h"
>> #include "hw/i386/apic_internal.h"
>> @@ -6409,8 +6410,21 @@ static void x86_cpu_filter_features(X86CPU *cpu, bool verbose)
>>
>> static void x86_cpu_hyperv_realize(X86CPU *cpu)
>> {
>> + X86MachineState *x86ms = X86_MACHINE(qdev_get_machine());
>> + X86MachineClass *x86mc = X86_MACHINE_GET_CLASS(x86ms);
>> + uint64_t feat;
>> size_t len;
>>
>> + if (x86ms->hyperv_enabled) {
>> + feat = x86mc->hyperv_features;
>> + /* Enlightened VMCS is only available on Intel/VMX */
>> + if (!cpu_has_vmx(&cpu->env)) {
>> + feat &= ~BIT(HYPERV_FEAT_EVMCS);
>> + }
>> +
>> + cpu->hyperv_features |= feat;
>> + }
>> +
>> /* Hyper-V vendor id */
>> if (!cpu->hyperv_vendor) {
>> object_property_set_str(OBJECT(cpu), "hv-vendor-id", "Microsoft Hv",
>> --
>> 2.25.4
>>
--
Vitaly
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