diff options
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 6 | ||||
| -rw-r--r-- | arch/x86/include/uapi/asm/kvm.h | 26 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 100 |
3 files changed, 131 insertions, 1 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index b3f2395a62d1..0e82fc5abd7b 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -2908,6 +2908,8 @@ such as set vcpu counter or reset vcpu, and they have the following id bit patte 0x9030 0000 0002 <reg:16> +x86 MSR registers have the following id bit patterns:: + 0x2030 0002 <msr number:32> 4.69 KVM_GET_ONE_REG -------------------- @@ -3588,7 +3590,7 @@ VCPU matching underlying host. --------------------- :Capability: basic -:Architectures: arm64, mips, riscv +:Architectures: arm64, mips, riscv, x86 (if KVM_CAP_ONE_REG) :Type: vcpu ioctl :Parameters: struct kvm_reg_list (in/out) :Returns: 0 on success; -1 on error @@ -3631,6 +3633,8 @@ Note that s390 does not support KVM_GET_REG_LIST for historical reasons - KVM_REG_S390_GBEA +Note, for x86, all MSRs enumerated by KVM_GET_MSR_INDEX_LIST are supported as +type KVM_X86_REG_TYPE_MSR, but are NOT enumerated via KVM_GET_REG_LIST. 4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated) ----------------------------------------- diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h index 0f15d683817d..aae1033c8afa 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -411,6 +411,32 @@ struct kvm_xcrs { __u64 padding[16]; }; +#define KVM_X86_REG_TYPE_MSR 2 +#define KVM_X86_REG_TYPE_KVM 3 + +#define KVM_X86_KVM_REG_SIZE(reg) \ +({ \ + reg == KVM_REG_GUEST_SSP ? KVM_REG_SIZE_U64 : 0; \ +}) + +#define KVM_X86_REG_TYPE_SIZE(type, reg) \ +({ \ + __u64 type_size = (__u64)type << 32; \ + \ + type_size |= type == KVM_X86_REG_TYPE_MSR ? KVM_REG_SIZE_U64 : \ + type == KVM_X86_REG_TYPE_KVM ? KVM_X86_KVM_REG_SIZE(reg) : \ + 0; \ + type_size; \ +}) + +#define KVM_X86_REG_ID(type, index) \ + (KVM_REG_X86 | KVM_X86_REG_TYPE_SIZE(type, index) | index) + +#define KVM_X86_REG_MSR(index) \ + KVM_X86_REG_ID(KVM_X86_REG_TYPE_MSR, index) +#define KVM_X86_REG_KVM(index) \ + KVM_X86_REG_ID(KVM_X86_REG_TYPE_KVM, index) + #define KVM_SYNC_X86_REGS (1UL << 0) #define KVM_SYNC_X86_SREGS (1UL << 1) #define KVM_SYNC_X86_EVENTS (1UL << 2) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f718834bc00b..bc245e0b0443 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4735,6 +4735,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_IRQFD_RESAMPLE: case KVM_CAP_MEMORY_FAULT_INFO: case KVM_CAP_X86_GUEST_MODE: + case KVM_CAP_ONE_REG: r = 1; break; case KVM_CAP_PRE_FAULT_MEMORY: @@ -5913,6 +5914,98 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, } } +struct kvm_x86_reg_id { + __u32 index; + __u8 type; + __u8 rsvd1; + __u8 rsvd2:4; + __u8 size:4; + __u8 x86; +}; + +static int kvm_translate_kvm_reg(struct kvm_x86_reg_id *reg) +{ + return -EINVAL; +} + +static int kvm_get_one_msr(struct kvm_vcpu *vcpu, u32 msr, u64 __user *user_val) +{ + u64 val; + + if (do_get_msr(vcpu, msr, &val)) + return -EINVAL; + + if (put_user(val, user_val)) + return -EFAULT; + + return 0; +} + +static int kvm_set_one_msr(struct kvm_vcpu *vcpu, u32 msr, u64 __user *user_val) +{ + u64 val; + + if (get_user(val, user_val)) + return -EFAULT; + + if (do_set_msr(vcpu, msr, &val)) + return -EINVAL; + + return 0; +} + +static int kvm_get_set_one_reg(struct kvm_vcpu *vcpu, unsigned int ioctl, + void __user *argp) +{ + struct kvm_one_reg one_reg; + struct kvm_x86_reg_id *reg; + u64 __user *user_val; + int r; + + if (copy_from_user(&one_reg, argp, sizeof(one_reg))) + return -EFAULT; + + if ((one_reg.id & KVM_REG_ARCH_MASK) != KVM_REG_X86) + return -EINVAL; + + reg = (struct kvm_x86_reg_id *)&one_reg.id; + if (reg->rsvd1 || reg->rsvd2) + return -EINVAL; + + if (reg->type == KVM_X86_REG_TYPE_KVM) { + r = kvm_translate_kvm_reg(reg); + if (r) + return r; + } + + if (reg->type != KVM_X86_REG_TYPE_MSR) + return -EINVAL; + + if ((one_reg.id & KVM_REG_SIZE_MASK) != KVM_REG_SIZE_U64) + return -EINVAL; + + guard(srcu)(&vcpu->kvm->srcu); + + user_val = u64_to_user_ptr(one_reg.addr); + if (ioctl == KVM_GET_ONE_REG) + r = kvm_get_one_msr(vcpu, reg->index, user_val); + else + r = kvm_set_one_msr(vcpu, reg->index, user_val); + + return r; +} + +static int kvm_get_reg_list(struct kvm_vcpu *vcpu, + struct kvm_reg_list __user *user_list) +{ + u64 nr_regs = 0; + + if (put_user(nr_regs, &user_list->n)) + return -EFAULT; + + return 0; +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -6029,6 +6122,13 @@ long kvm_arch_vcpu_ioctl(struct file *filp, srcu_read_unlock(&vcpu->kvm->srcu, idx); break; } + case KVM_GET_ONE_REG: + case KVM_SET_ONE_REG: + r = kvm_get_set_one_reg(vcpu, ioctl, argp); + break; + case KVM_GET_REG_LIST: + r = kvm_get_reg_list(vcpu, argp); + break; case KVM_TPR_ACCESS_REPORTING: { struct kvm_tpr_access_ctl tac; |