[PATCH v2 29/43] arm64: rme: Allow checking SVE on VM instance

From: Steven Price
Date: Fri Apr 12 2024 - 04:57:12 EST


From: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

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@xxxxxxx>
Signed-off-by: Steven Price <steven.price@xxxxxxx>
---
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 fef04706ff9d..62d1fa82ac92 100644
--- a/arch/arm64/include/asm/kvm_rme.h
+++ b/arch/arm64/include/asm/kvm_rme.h
@@ -89,6 +89,8 @@ struct realm_rec {
int kvm_init_rme(void);
u32 kvm_realm_ipa_limit(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 f2279ab45add..dcd9089877f3 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -363,7 +363,10 @@ 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 && 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 9544653accb6..9593e8e35913 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;
--
2.34.1