diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c index fb7c4e07961f..a9f083feeb76 100644 --- a/arch/riscv/kvm/vm.c +++ b/arch/riscv/kvm/vm.c @@ -214,12 +214,52 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { + if (cap->flags) + return -EINVAL; + switch (cap->cap) { case KVM_CAP_RISCV_MP_STATE_RESET: - if (cap->flags) - return -EINVAL; kvm->arch.mp_state_reset = true; return 0; + case KVM_CAP_VM_GPA_BITS: { + unsigned long gpa_bits = cap->args[0]; + unsigned long new_levels; + int r = 0; + + /* Decide target pgd levels from requested gpa_bits */ +#ifdef CONFIG_64BIT + if (gpa_bits <= 41) + new_levels = 3; /* Sv39x4 */ + else if (gpa_bits <= 50) + new_levels = 4; /* Sv48x4 */ + else if (gpa_bits <= 59) + new_levels = 5; /* Sv57x4 */ + else + return -EINVAL; +#else + /* 32-bit: only Sv32x4*/ + if (gpa_bits <= 34) + new_levels = 2; + else + return -EINVAL; +#endif + if (new_levels > kvm_riscv_gstage_max_pgd_levels) + return -EINVAL; + + /* Follow KVM's lock ordering: kvm->lock -> kvm->slots_lock. */ + mutex_lock(&kvm->lock); + mutex_lock(&kvm->slots_lock); + + if (kvm->created_vcpus || !kvm_are_all_memslots_empty(kvm)) + r = -EBUSY; + else + kvm->arch.pgd_levels = new_levels; + + mutex_unlock(&kvm->slots_lock); + mutex_unlock(&kvm->lock); + + return r; + } default: return -EINVAL; }