diff mbox series

[3/3] Enable nested virtualization support in arm64 KVM mode

Message ID b7c2626e6c720ccc43e57197dff3dac72d613640.1616052890.git.haibo.xu@linaro.org
State New
Headers show
Series target/arm: Add nested virtualization support | expand

Commit Message

Haibo Xu March 22, 2021, 10:07 a.m. UTC
Add support for arm64 el2 in qemu KVM mode(nested virtualization).
This feature is disabled by default, just as that in TCG mode, and
can be enabled by "-M virt,accel=kvm,virtualization=on" when starting
a VM.

Signed-off-by: Haibo Xu <haibo.xu@linaro.org>

---
 hw/arm/virt.c        | 11 ++++++++---
 target/arm/cpu.h     |  8 ++++++++
 target/arm/kvm64.c   | 14 ++++++++++++++
 target/arm/kvm_arm.h | 28 ++++++++++++++++++++++++++++
 4 files changed, 58 insertions(+), 3 deletions(-)

-- 
2.17.1

Comments

Andrew Jones March 22, 2021, 10:48 a.m. UTC | #1
On Mon, Mar 22, 2021 at 10:07:26AM +0000, Haibo Xu wrote:
> Add support for arm64 el2 in qemu KVM mode(nested virtualization).

> This feature is disabled by default, just as that in TCG mode, and

> can be enabled by "-M virt,accel=kvm,virtualization=on" when starting

> a VM.

> 

> Signed-off-by: Haibo Xu <haibo.xu@linaro.org>

> ---

>  hw/arm/virt.c        | 11 ++++++++---

>  target/arm/cpu.h     |  8 ++++++++

>  target/arm/kvm64.c   | 14 ++++++++++++++

>  target/arm/kvm_arm.h | 28 ++++++++++++++++++++++++++++

>  4 files changed, 58 insertions(+), 3 deletions(-)

> 

> diff --git a/hw/arm/virt.c b/hw/arm/virt.c

> index aa2bbd14e0..72e60348d5 100644

> --- a/hw/arm/virt.c

> +++ b/hw/arm/virt.c

> @@ -663,6 +663,11 @@ static void create_gic(VirtMachineState *vms)

>              qdev_prop_set_uint32(vms->gic, "redist-region-count[1]",

>                  MIN(smp_cpus - redist0_count, redist1_capacity));

>          }

> +

> +        if (kvm_irqchip_in_kernel()) {

> +            qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",

> +                              vms->virt);

> +        }

>      } else {

>          if (!kvm_irqchip_in_kernel()) {

>              qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",

> @@ -1905,9 +1910,9 @@ static void machvirt_init(MachineState *machine)

>          exit(1);

>      }

>  

> -    if (vms->virt && kvm_enabled()) {

> -        error_report("mach-virt: KVM does not support providing "

> -                     "Virtualization extensions to the guest CPU");

> +    if (vms->virt && kvm_enabled() && !kvm_arm_nested_virt_supported()) {

> +        error_report("mach-virt: nested virtualization requested, "

> +                     "but not supported by the host.");

>          exit(1);

>      }

>  

> diff --git a/target/arm/cpu.h b/target/arm/cpu.h

> index 193a49ec7f..377187152b 100644

> --- a/target/arm/cpu.h

> +++ b/target/arm/cpu.h

> @@ -4182,6 +4182,14 @@ static inline bool isar_feature_aa64_ssbs(const ARMISARegisters *id)

>      return FIELD_EX64(id->id_aa64pfr1, ID_AA64PFR1, SSBS) != 0;

>  }

>  

> +/*

> + * Currently we don't differentiate between the ARMv8.3-NV and ARMv8.4-NV.

> + */

> +static inline bool isar_feature_aa64_nv(const ARMISARegisters *id)

> +{

> +    return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, NV) != 0;

> +}


What calls this function?

> +

>  /*

>   * Feature tests for "does this exist in either 32-bit or 64-bit?"

>   */

> diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c

> index dff85f6db9..2810104dea 100644

> --- a/target/arm/kvm64.c

> +++ b/target/arm/kvm64.c

> @@ -500,6 +500,7 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

>       */

>      int fdarray[3];

>      bool sve_supported;

> +    bool el2_supported;

>      uint64_t features = 0;

>      uint64_t t;

>      int err;

> @@ -646,6 +647,7 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

>      }

>  

>      sve_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_SVE) > 0;

> +    el2_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_EL2) > 0;

>  

>      kvm_arm_destroy_scratch_host_vcpu(fdarray);

>  

> @@ -671,6 +673,10 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

>      features |= 1ULL << ARM_FEATURE_PMU;

>      features |= 1ULL << ARM_FEATURE_GENERIC_TIMER;

>  

> +    if (el2_supported) {

> +        features |= 1ULL << ARM_FEATURE_EL2;

> +    }

> +

>      ahcf->features = features;

>  

>      return true;

> @@ -721,6 +727,11 @@ bool kvm_arm_steal_time_supported(void)

>      return kvm_check_extension(kvm_state, KVM_CAP_STEAL_TIME);

>  }

>  

> +bool kvm_arm_nested_virt_supported(void)

> +{

> +    return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL2);

> +}

> +

>  QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1);

>  

>  void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)

> @@ -856,6 +867,9 @@ int kvm_arch_init_vcpu(CPUState *cs)

>          assert(kvm_arm_sve_supported());

>          cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SVE;

>      }

> +    if (cpu->has_el2) {

> +        cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_HAS_EL2;

> +    }

>  

>      /* Do KVM_ARM_VCPU_INIT ioctl */

>      ret = kvm_arm_vcpu_init(cs);

> diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h

> index 34f8daa377..da3a3d5920 100644

> --- a/target/arm/kvm_arm.h

> +++ b/target/arm/kvm_arm.h

> @@ -285,6 +285,24 @@ void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp);

>   */

>  bool kvm_arm_steal_time_supported(void);

>  

> +/**

> + * kvm_arm_nested_virt_finalize:

> + * @cpu: ARMCPU for which to finalize nested-virt

> + * @errp: Pointer to Error* for error propagation

> + *

> + * Validate the nested-virt property selection and set its default

> + * based on KVM support and guest configuration.

> + */

> +void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp);


Where is this function defined? From where is it called?

> +

> +/**

> + * kvm_arm_nested_virt_supported:

> + *

> + * Returns: true if KVM can enable nested virtualization

> + * and false otherwise.

> + */

> +bool kvm_arm_nested_virt_supported(void);

> +

>  /**

>   * kvm_arm_aarch32_supported:

>   *

> @@ -398,6 +416,11 @@ static inline bool kvm_arm_steal_time_supported(void)

>      return false;

>  }

>  

> +static inline bool kvm_arm_nested_virt_supported(void)

> +{

> +    return false;

> +}

> +

>  /*

>   * These functions should never actually be called without KVM support.

>   */

> @@ -441,6 +464,11 @@ static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)

>      g_assert_not_reached();

>  }

>  

> +static inline void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp)

> +{

> +    g_assert_not_reached();

> +}

> +

>  static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)

>  {

>      g_assert_not_reached();

> -- 

> 2.17.1

>


Thanks,
drew
Haibo Xu March 23, 2021, 7:08 a.m. UTC | #2
On Mon, 22 Mar 2021 at 18:49, Andrew Jones <drjones@redhat.com> wrote:
>

> On Mon, Mar 22, 2021 at 10:07:26AM +0000, Haibo Xu wrote:

> > Add support for arm64 el2 in qemu KVM mode(nested virtualization).

> > This feature is disabled by default, just as that in TCG mode, and

> > can be enabled by "-M virt,accel=kvm,virtualization=on" when starting

> > a VM.

> >

> > Signed-off-by: Haibo Xu <haibo.xu@linaro.org>

> > ---

> >  hw/arm/virt.c        | 11 ++++++++---

> >  target/arm/cpu.h     |  8 ++++++++

> >  target/arm/kvm64.c   | 14 ++++++++++++++

> >  target/arm/kvm_arm.h | 28 ++++++++++++++++++++++++++++

> >  4 files changed, 58 insertions(+), 3 deletions(-)

> >

> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c

> > index aa2bbd14e0..72e60348d5 100644

> > --- a/hw/arm/virt.c

> > +++ b/hw/arm/virt.c

> > @@ -663,6 +663,11 @@ static void create_gic(VirtMachineState *vms)

> >              qdev_prop_set_uint32(vms->gic, "redist-region-count[1]",

> >                  MIN(smp_cpus - redist0_count, redist1_capacity));

> >          }

> > +

> > +        if (kvm_irqchip_in_kernel()) {

> > +            qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",

> > +                              vms->virt);

> > +        }

> >      } else {

> >          if (!kvm_irqchip_in_kernel()) {

> >              qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",

> > @@ -1905,9 +1910,9 @@ static void machvirt_init(MachineState *machine)

> >          exit(1);

> >      }

> >

> > -    if (vms->virt && kvm_enabled()) {

> > -        error_report("mach-virt: KVM does not support providing "

> > -                     "Virtualization extensions to the guest CPU");

> > +    if (vms->virt && kvm_enabled() && !kvm_arm_nested_virt_supported()) {

> > +        error_report("mach-virt: nested virtualization requested, "

> > +                     "but not supported by the host.");

> >          exit(1);

> >      }

> >

> > diff --git a/target/arm/cpu.h b/target/arm/cpu.h

> > index 193a49ec7f..377187152b 100644

> > --- a/target/arm/cpu.h

> > +++ b/target/arm/cpu.h

> > @@ -4182,6 +4182,14 @@ static inline bool isar_feature_aa64_ssbs(const ARMISARegisters *id)

> >      return FIELD_EX64(id->id_aa64pfr1, ID_AA64PFR1, SSBS) != 0;

> >  }

> >

> > +/*

> > + * Currently we don't differentiate between the ARMv8.3-NV and ARMv8.4-NV.

> > + */

> > +static inline bool isar_feature_aa64_nv(const ARMISARegisters *id)

> > +{

> > +    return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, NV) != 0;

> > +}

>

> What calls this function?

>


Sorry for the noise here! This function should be deleted in this patch!

Previously, I wanted to follow the SVE vCPU feature when adding the NV support,
and the above function is supposed to be used for the feature probe.

Thanks,
Haibo

> > +

> >  /*

> >   * Feature tests for "does this exist in either 32-bit or 64-bit?"

> >   */

> > diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c

> > index dff85f6db9..2810104dea 100644

> > --- a/target/arm/kvm64.c

> > +++ b/target/arm/kvm64.c

> > @@ -500,6 +500,7 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

> >       */

> >      int fdarray[3];

> >      bool sve_supported;

> > +    bool el2_supported;

> >      uint64_t features = 0;

> >      uint64_t t;

> >      int err;

> > @@ -646,6 +647,7 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

> >      }

> >

> >      sve_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_SVE) > 0;

> > +    el2_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_EL2) > 0;

> >

> >      kvm_arm_destroy_scratch_host_vcpu(fdarray);

> >

> > @@ -671,6 +673,10 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)

> >      features |= 1ULL << ARM_FEATURE_PMU;

> >      features |= 1ULL << ARM_FEATURE_GENERIC_TIMER;

> >

> > +    if (el2_supported) {

> > +        features |= 1ULL << ARM_FEATURE_EL2;

> > +    }

> > +

> >      ahcf->features = features;

> >

> >      return true;

> > @@ -721,6 +727,11 @@ bool kvm_arm_steal_time_supported(void)

> >      return kvm_check_extension(kvm_state, KVM_CAP_STEAL_TIME);

> >  }

> >

> > +bool kvm_arm_nested_virt_supported(void)

> > +{

> > +    return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL2);

> > +}

> > +

> >  QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1);

> >

> >  void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)

> > @@ -856,6 +867,9 @@ int kvm_arch_init_vcpu(CPUState *cs)

> >          assert(kvm_arm_sve_supported());

> >          cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SVE;

> >      }

> > +    if (cpu->has_el2) {

> > +        cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_HAS_EL2;

> > +    }

> >

> >      /* Do KVM_ARM_VCPU_INIT ioctl */

> >      ret = kvm_arm_vcpu_init(cs);

> > diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h

> > index 34f8daa377..da3a3d5920 100644

> > --- a/target/arm/kvm_arm.h

> > +++ b/target/arm/kvm_arm.h

> > @@ -285,6 +285,24 @@ void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp);

> >   */

> >  bool kvm_arm_steal_time_supported(void);

> >

> > +/**

> > + * kvm_arm_nested_virt_finalize:

> > + * @cpu: ARMCPU for which to finalize nested-virt

> > + * @errp: Pointer to Error* for error propagation

> > + *

> > + * Validate the nested-virt property selection and set its default

> > + * based on KVM support and guest configuration.

> > + */

> > +void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp);

>

> Where is this function defined? From where is it called?

>


Same reason here!

> > +

> > +/**

> > + * kvm_arm_nested_virt_supported:

> > + *

> > + * Returns: true if KVM can enable nested virtualization

> > + * and false otherwise.

> > + */

> > +bool kvm_arm_nested_virt_supported(void);

> > +

> >  /**

> >   * kvm_arm_aarch32_supported:

> >   *

> > @@ -398,6 +416,11 @@ static inline bool kvm_arm_steal_time_supported(void)

> >      return false;

> >  }

> >

> > +static inline bool kvm_arm_nested_virt_supported(void)

> > +{

> > +    return false;

> > +}

> > +

> >  /*

> >   * These functions should never actually be called without KVM support.

> >   */

> > @@ -441,6 +464,11 @@ static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)

> >      g_assert_not_reached();

> >  }

> >

> > +static inline void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp)

> > +{

> > +    g_assert_not_reached();

> > +}

> > +

> >  static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)

> >  {

> >      g_assert_not_reached();

> > --

> > 2.17.1

> >

>

> Thanks,

> drew

>
diff mbox series

Patch

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index aa2bbd14e0..72e60348d5 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -663,6 +663,11 @@  static void create_gic(VirtMachineState *vms)
             qdev_prop_set_uint32(vms->gic, "redist-region-count[1]",
                 MIN(smp_cpus - redist0_count, redist1_capacity));
         }
+
+        if (kvm_irqchip_in_kernel()) {
+            qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",
+                              vms->virt);
+        }
     } else {
         if (!kvm_irqchip_in_kernel()) {
             qdev_prop_set_bit(vms->gic, "has-virtualization-extensions",
@@ -1905,9 +1910,9 @@  static void machvirt_init(MachineState *machine)
         exit(1);
     }
 
-    if (vms->virt && kvm_enabled()) {
-        error_report("mach-virt: KVM does not support providing "
-                     "Virtualization extensions to the guest CPU");
+    if (vms->virt && kvm_enabled() && !kvm_arm_nested_virt_supported()) {
+        error_report("mach-virt: nested virtualization requested, "
+                     "but not supported by the host.");
         exit(1);
     }
 
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 193a49ec7f..377187152b 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -4182,6 +4182,14 @@  static inline bool isar_feature_aa64_ssbs(const ARMISARegisters *id)
     return FIELD_EX64(id->id_aa64pfr1, ID_AA64PFR1, SSBS) != 0;
 }
 
+/*
+ * Currently we don't differentiate between the ARMv8.3-NV and ARMv8.4-NV.
+ */
+static inline bool isar_feature_aa64_nv(const ARMISARegisters *id)
+{
+    return FIELD_EX64(id->id_aa64mmfr2, ID_AA64MMFR2, NV) != 0;
+}
+
 /*
  * Feature tests for "does this exist in either 32-bit or 64-bit?"
  */
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index dff85f6db9..2810104dea 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -500,6 +500,7 @@  bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
      */
     int fdarray[3];
     bool sve_supported;
+    bool el2_supported;
     uint64_t features = 0;
     uint64_t t;
     int err;
@@ -646,6 +647,7 @@  bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
     }
 
     sve_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_SVE) > 0;
+    el2_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_EL2) > 0;
 
     kvm_arm_destroy_scratch_host_vcpu(fdarray);
 
@@ -671,6 +673,10 @@  bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
     features |= 1ULL << ARM_FEATURE_PMU;
     features |= 1ULL << ARM_FEATURE_GENERIC_TIMER;
 
+    if (el2_supported) {
+        features |= 1ULL << ARM_FEATURE_EL2;
+    }
+
     ahcf->features = features;
 
     return true;
@@ -721,6 +727,11 @@  bool kvm_arm_steal_time_supported(void)
     return kvm_check_extension(kvm_state, KVM_CAP_STEAL_TIME);
 }
 
+bool kvm_arm_nested_virt_supported(void)
+{
+    return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL2);
+}
+
 QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1);
 
 void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
@@ -856,6 +867,9 @@  int kvm_arch_init_vcpu(CPUState *cs)
         assert(kvm_arm_sve_supported());
         cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SVE;
     }
+    if (cpu->has_el2) {
+        cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_HAS_EL2;
+    }
 
     /* Do KVM_ARM_VCPU_INIT ioctl */
     ret = kvm_arm_vcpu_init(cs);
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 34f8daa377..da3a3d5920 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -285,6 +285,24 @@  void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp);
  */
 bool kvm_arm_steal_time_supported(void);
 
+/**
+ * kvm_arm_nested_virt_finalize:
+ * @cpu: ARMCPU for which to finalize nested-virt
+ * @errp: Pointer to Error* for error propagation
+ *
+ * Validate the nested-virt property selection and set its default
+ * based on KVM support and guest configuration.
+ */
+void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp);
+
+/**
+ * kvm_arm_nested_virt_supported:
+ *
+ * Returns: true if KVM can enable nested virtualization
+ * and false otherwise.
+ */
+bool kvm_arm_nested_virt_supported(void);
+
 /**
  * kvm_arm_aarch32_supported:
  *
@@ -398,6 +416,11 @@  static inline bool kvm_arm_steal_time_supported(void)
     return false;
 }
 
+static inline bool kvm_arm_nested_virt_supported(void)
+{
+    return false;
+}
+
 /*
  * These functions should never actually be called without KVM support.
  */
@@ -441,6 +464,11 @@  static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)
     g_assert_not_reached();
 }
 
+static inline void kvm_arm_nested_virt_finalize(ARMCPU *cpu, Error **errp)
+{
+    g_assert_not_reached();
+}
+
 static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
 {
     g_assert_not_reached();