diff options
Diffstat (limited to 'arch/arm64/kvm/arm.c')
-rw-r--r-- | arch/arm64/kvm/arm.c | 50 |
1 files changed, 41 insertions, 9 deletions
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index c4a0a35e02..6cda738a41 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -195,6 +195,23 @@ void kvm_arch_create_vm_debugfs(struct kvm *kvm) kvm_sys_regs_create_debugfs(kvm); } +static void kvm_destroy_mpidr_data(struct kvm *kvm) +{ + struct kvm_mpidr_data *data; + + mutex_lock(&kvm->arch.config_lock); + + data = rcu_dereference_protected(kvm->arch.mpidr_data, + lockdep_is_held(&kvm->arch.config_lock)); + if (data) { + rcu_assign_pointer(kvm->arch.mpidr_data, NULL); + synchronize_rcu(); + kfree(data); + } + + mutex_unlock(&kvm->arch.config_lock); +} + /** * kvm_arch_destroy_vm - destroy the VM data structure * @kvm: pointer to the KVM struct @@ -209,7 +226,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm) if (is_protected_kvm_enabled()) pkvm_destroy_hyp_vm(kvm); - kfree(kvm->arch.mpidr_data); + kvm_destroy_mpidr_data(kvm); + kfree(kvm->arch.sysreg_masks); kvm_destroy_vcpus(kvm); @@ -395,6 +413,13 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu; + /* + * This vCPU may have been created after mpidr_data was initialized. + * Throw out the pre-computed mappings if that is the case which forces + * KVM to fall back to iteratively searching the vCPUs. + */ + kvm_destroy_mpidr_data(vcpu->kvm); + err = kvm_vgic_vcpu_init(vcpu); if (err) return err; @@ -594,7 +619,8 @@ static void kvm_init_mpidr_data(struct kvm *kvm) mutex_lock(&kvm->arch.config_lock); - if (kvm->arch.mpidr_data || atomic_read(&kvm->online_vcpus) == 1) + if (rcu_access_pointer(kvm->arch.mpidr_data) || + atomic_read(&kvm->online_vcpus) == 1) goto out; kvm_for_each_vcpu(c, vcpu, kvm) { @@ -631,7 +657,7 @@ static void kvm_init_mpidr_data(struct kvm *kvm) data->cmpidr_to_idx[index] = c; } - kvm->arch.mpidr_data = data; + rcu_assign_pointer(kvm->arch.mpidr_data, data); out: mutex_unlock(&kvm->arch.config_lock); } @@ -2470,21 +2496,27 @@ out_err: struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) { - struct kvm_vcpu *vcpu; + struct kvm_vcpu *vcpu = NULL; + struct kvm_mpidr_data *data; unsigned long i; mpidr &= MPIDR_HWID_BITMASK; - if (kvm->arch.mpidr_data) { - u16 idx = kvm_mpidr_index(kvm->arch.mpidr_data, mpidr); + rcu_read_lock(); + data = rcu_dereference(kvm->arch.mpidr_data); - vcpu = kvm_get_vcpu(kvm, - kvm->arch.mpidr_data->cmpidr_to_idx[idx]); + if (data) { + u16 idx = kvm_mpidr_index(data, mpidr); + + vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]); if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu)) vcpu = NULL; + } + rcu_read_unlock(); + + if (vcpu) return vcpu; - } kvm_for_each_vcpu(i, vcpu, kvm) { if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu)) |