KVM: arm64: Free sve_state via arm specific hook

Add an arm specific hook to free the arm64-only sve_state.  Doing so
eliminates the last functional code from kvm_arch_vcpu_uninit() across
all architectures and paves the way for removing kvm_arch_vcpu_init()
and kvm_arch_vcpu_uninit() entirely.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/arm/include/asm/kvm_host.h

@@ -366,6 +366,7 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
 static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
 static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arm_vcpu_destroy(struct kvm_vcpu *vcpu) {}
 
 static inline void kvm_arm_init_debug(void) {}
 static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {}

arch/arm64/include/asm/kvm_host.h

@@ -53,6 +53,7 @@ int kvm_arm_init_sve(void);
 
 int __attribute_const__ kvm_target_cpu(void);
 int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
+void kvm_arm_vcpu_destroy(struct kvm_vcpu *vcpu);
 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu);
 int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext);
 void __extended_idmap_trampoline(phys_addr_t boot_pgd, phys_addr_t idmap_start);

arch/arm64/kvm/reset.c

@@ -205,6 +205,11 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu)
 }
 
 void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
+{
+
+}
+
+void kvm_arm_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
 	kfree(vcpu->arch.sve_state);
 }

virt/kvm/arm/arm.c

@@ -326,6 +326,8 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 	kvm_mmu_free_memory_caches(vcpu);
 	kvm_timer_vcpu_terminate(vcpu);
 	kvm_pmu_vcpu_destroy(vcpu);
+
+	kvm_arm_vcpu_destroy(vcpu);
 }
 
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)