| Message ID | 20241212155610.76522-29-steven.price@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: Support for Arm CCA in KVM | expand |
On 12/13/24 1:55 AM, Steven Price wrote: > From: Suzuki K Poulose <suzuki.poulose@arm.com> > > Given we have different types of VMs supported, check the > support for SVE for the given instance of the VM to accurately > report the status. > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Steven Price <steven.price@arm.com> > --- > arch/arm64/include/asm/kvm_rme.h | 2 ++ > arch/arm64/kvm/arm.c | 5 ++++- > arch/arm64/kvm/rme.c | 5 +++++ > 3 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h > index 90a4537ad38d..0d89ab1645c1 100644 > --- a/arch/arm64/include/asm/kvm_rme.h > +++ b/arch/arm64/include/asm/kvm_rme.h > @@ -85,6 +85,8 @@ void kvm_init_rme(void); > u32 kvm_realm_ipa_limit(void); > u32 kvm_realm_vgic_nr_lr(void); > > +bool kvm_rme_supports_sve(void); > + > int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap); > int kvm_init_realm_vm(struct kvm *kvm); > void kvm_destroy_realm(struct kvm *kvm); > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 134acb4ee26f..6f7f96ab781d 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -456,7 +456,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > r = get_kvm_ipa_limit(); > break; > case KVM_CAP_ARM_SVE: > - r = system_supports_sve(); > + if (kvm_is_realm(kvm)) > + r = kvm_rme_supports_sve(); > + else > + r = system_supports_sve(); > break; kvm_vm_ioctl_check_extension() can be called by ioctl(KVM_CHECK_EXTENSION) on the file descriptor of '/dev/kvm'. kvm is NULL and kvm_is_realm() returns false in this case. kvm_dev_ioctl kvm_vm_ioctl_check_extension_generic // kvm is NULL kvm_vm_ioctl_check_extension > case KVM_CAP_ARM_PTRAUTH_ADDRESS: > case KVM_CAP_ARM_PTRAUTH_GENERIC: > diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c > index 5831d379760a..27a479feb907 100644 > --- a/arch/arm64/kvm/rme.c > +++ b/arch/arm64/kvm/rme.c > @@ -20,6 +20,11 @@ static bool rme_supports(unsigned long feature) > return !!u64_get_bits(rmm_feat_reg0, feature); > } > > +bool kvm_rme_supports_sve(void) > +{ > + return rme_supports(RMI_FEATURE_REGISTER_0_SVE_EN); > +} > + If rme_supports() becomes a public helper, it can be directly used. In turn, kvm_rme_supports_sve() can be dropped. RMI_FEATURE_REGISTER_0_SVE_EN is obvious to indicate the corresponding feature. > static int rmi_check_version(void) > { > struct arm_smccc_res res; Thanks, Gavin
On 02/02/2025 06:00, Gavin Shan wrote: > On 12/13/24 1:55 AM, Steven Price wrote: >> From: Suzuki K Poulose <suzuki.poulose@arm.com> >> >> Given we have different types of VMs supported, check the >> support for SVE for the given instance of the VM to accurately >> report the status. >> >> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> >> Signed-off-by: Steven Price <steven.price@arm.com> >> --- >> arch/arm64/include/asm/kvm_rme.h | 2 ++ >> arch/arm64/kvm/arm.c | 5 ++++- >> arch/arm64/kvm/rme.c | 5 +++++ >> 3 files changed, 11 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/ >> asm/kvm_rme.h >> index 90a4537ad38d..0d89ab1645c1 100644 >> --- a/arch/arm64/include/asm/kvm_rme.h >> +++ b/arch/arm64/include/asm/kvm_rme.h >> @@ -85,6 +85,8 @@ void kvm_init_rme(void); >> u32 kvm_realm_ipa_limit(void); >> u32 kvm_realm_vgic_nr_lr(void); >> +bool kvm_rme_supports_sve(void); >> + >> int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap); >> int kvm_init_realm_vm(struct kvm *kvm); >> void kvm_destroy_realm(struct kvm *kvm); >> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c >> index 134acb4ee26f..6f7f96ab781d 100644 >> --- a/arch/arm64/kvm/arm.c >> +++ b/arch/arm64/kvm/arm.c >> @@ -456,7 +456,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, >> long ext) >> r = get_kvm_ipa_limit(); >> break; >> case KVM_CAP_ARM_SVE: >> - r = system_supports_sve(); >> + if (kvm_is_realm(kvm)) >> + r = kvm_rme_supports_sve(); >> + else >> + r = system_supports_sve(); >> break; > > kvm_vm_ioctl_check_extension() can be called by > ioctl(KVM_CHECK_EXTENSION) on the > file descriptor of '/dev/kvm'. kvm is NULL and kvm_is_realm() returns > false in > this case. > > kvm_dev_ioctl > kvm_vm_ioctl_check_extension_generic // kvm is NULL > kvm_vm_ioctl_check_extension See my reply in patch 25 >> case KVM_CAP_ARM_PTRAUTH_ADDRESS: >> case KVM_CAP_ARM_PTRAUTH_GENERIC: >> diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c >> index 5831d379760a..27a479feb907 100644 >> --- a/arch/arm64/kvm/rme.c >> +++ b/arch/arm64/kvm/rme.c >> @@ -20,6 +20,11 @@ static bool rme_supports(unsigned long feature) >> return !!u64_get_bits(rmm_feat_reg0, feature); >> } >> +bool kvm_rme_supports_sve(void) >> +{ >> + return rme_supports(RMI_FEATURE_REGISTER_0_SVE_EN); >> +} >> + > > If rme_supports() becomes a public helper, it can be directly used. In > turn, > kvm_rme_supports_sve() can be dropped. RMI_FEATURE_REGISTER_0_SVE_EN is > obvious > to indicate the corresponding feature. I agree this seem reasonable. Sadly the use of u64_get_bits() is assuming that the 'feature' parameter is constant at runtime. I could rework it to not require a constant, but considering this is the only function which is exposing rme_supports() without any further checks I feel it's better to leave the code as it is. Obviously if we get more feature bits like this in the future then it would be worth revisiting. Thanks, Steve >> static int rmi_check_version(void) >> { >> struct arm_smccc_res res; > > Thanks, > Gavin >
diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h index 90a4537ad38d..0d89ab1645c1 100644 --- a/arch/arm64/include/asm/kvm_rme.h +++ b/arch/arm64/include/asm/kvm_rme.h @@ -85,6 +85,8 @@ void kvm_init_rme(void); u32 kvm_realm_ipa_limit(void); u32 kvm_realm_vgic_nr_lr(void); +bool kvm_rme_supports_sve(void); + int kvm_realm_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap); int kvm_init_realm_vm(struct kvm *kvm); void kvm_destroy_realm(struct kvm *kvm); diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 134acb4ee26f..6f7f96ab781d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -456,7 +456,10 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = get_kvm_ipa_limit(); break; case KVM_CAP_ARM_SVE: - r = system_supports_sve(); + if (kvm_is_realm(kvm)) + r = kvm_rme_supports_sve(); + else + r = system_supports_sve(); break; case KVM_CAP_ARM_PTRAUTH_ADDRESS: case KVM_CAP_ARM_PTRAUTH_GENERIC: diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c index 5831d379760a..27a479feb907 100644 --- a/arch/arm64/kvm/rme.c +++ b/arch/arm64/kvm/rme.c @@ -20,6 +20,11 @@ static bool rme_supports(unsigned long feature) return !!u64_get_bits(rmm_feat_reg0, feature); } +bool kvm_rme_supports_sve(void) +{ + return rme_supports(RMI_FEATURE_REGISTER_0_SVE_EN); +} + static int rmi_check_version(void) { struct arm_smccc_res res;