On Mon, 22 Mar 2021 at 18:49, Andrew Jones <drjo...@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...@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
>
