Re: [RFC PATCH 05/28] arm64: RME: Define the user ABI

Zhi Wang
2023-02-13T16:04:23Z

On Fri, 27 Jan 2023 11:29:09 +0000
Steven Price <steven.price@arm.com> wrote:

> There is one (multiplexed) CAP which can be used to create, populate and
> then activate the realm.
>
> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
> Documentation/virt/kvm/api.rst | 1 +
> arch/arm64/include/uapi/asm/kvm.h | 63 +++++++++++++++++++++++++++++++
> include/uapi/linux/kvm.h | 2 +
> 3 files changed, 66 insertions(+)
>
> diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
> index 0dd5d8733dd5..f1a59d6fb7fc 100644
> --- a/Documentation/virt/kvm/api.rst
> +++ b/Documentation/virt/kvm/api.rst
> @@ -4965,6 +4965,7 @@ Recognised values for feature:
>
> ===== ===========================================
> arm64 KVM_ARM_VCPU_SVE (requires KVM_CAP_ARM_SVE)
> + arm64 KVM_ARM_VCPU_REC (requires KVM_CAP_ARM_RME)
> ===== ===========================================
>
> Finalizes the configuration of the specified vcpu feature.
> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
> index a7a857f1784d..fcc0b8dce29b 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -109,6 +109,7 @@ struct kvm_regs {
> #define KVM_ARM_VCPU_SVE 4 /* enable SVE for this CPU */
> #define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* VCPU uses address authentication */
> #define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* VCPU uses generic authentication */
> +#define KVM_ARM_VCPU_REC 7 /* VCPU REC state as part of Realm */
>
> struct kvm_vcpu_init {
> __u32 target;
> @@ -401,6 +402,68 @@ enum {
> #define KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES 3
> #define KVM_DEV_ARM_ITS_CTRL_RESET 4
>
> +/* KVM_CAP_ARM_RME on VM fd */
> +#define KVM_CAP_ARM_RME_CONFIG_REALM 0
> +#define KVM_CAP_ARM_RME_CREATE_RD 1
> +#define KVM_CAP_ARM_RME_INIT_IPA_REALM 2
> +#define KVM_CAP_ARM_RME_POPULATE_REALM 3
> +#define KVM_CAP_ARM_RME_ACTIVATE_REALM 4
> +

It is a little bit confusing here. These seems more like 'commands' not caps.
Will leave more comments after reviewing the later patches.

> +#define KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA256 0
> +#define KVM_CAP_ARM_RME_MEASUREMENT_ALGO_SHA512 1
> +
> +#define KVM_CAP_ARM_RME_RPV_SIZE 64
> +
> +/* List of configuration items accepted for KVM_CAP_ARM_RME_CONFIG_REALM */
> +#define KVM_CAP_ARM_RME_CFG_RPV 0
> +#define KVM_CAP_ARM_RME_CFG_HASH_ALGO 1
> +#define KVM_CAP_ARM_RME_CFG_SVE 2
> +#define KVM_CAP_ARM_RME_CFG_DBG 3
> +#define KVM_CAP_ARM_RME_CFG_PMU 4
> +
> +struct kvm_cap_arm_rme_config_item {
> + __u32 cfg;
> + union {
> + /* cfg == KVM_CAP_ARM_RME_CFG_RPV */
> + struct {
> + __u8 rpv[KVM_CAP_ARM_RME_RPV_SIZE];
> + };
> +
> + /* cfg == KVM_CAP_ARM_RME_CFG_HASH_ALGO */
> + struct {
> + __u32 hash_algo;
> + };
> +
> + /* cfg == KVM_CAP_ARM_RME_CFG_SVE */
> + struct {
> + __u32 sve_vq;
> + };
> +
> + /* cfg == KVM_CAP_ARM_RME_CFG_DBG */
> + struct {
> + __u32 num_brps;
> + __u32 num_wrps;
> + };
> +
> + /* cfg == KVM_CAP_ARM_RME_CFG_PMU */
> + struct {
> + __u32 num_pmu_cntrs;
> + };
> + /* Fix the size of the union */
> + __u8 reserved[256];
> + };
> +};
> +
> +struct kvm_cap_arm_rme_populate_realm_args {
> + __u64 populate_ipa_base;
> + __u64 populate_ipa_size;
> +};
> +
> +struct kvm_cap_arm_rme_init_ipa_args {
> + __u64 init_ipa_base;
> + __u64 init_ipa_size;
> +};
> +
> /* Device Control API on vcpu fd */
> #define KVM_ARM_VCPU_PMU_V3_CTRL 0
> #define KVM_ARM_VCPU_PMU_V3_IRQ 0
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 20522d4ba1e0..fec1909e8b73 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1176,6 +1176,8 @@ struct kvm_ppc_resize_hpt {
> #define KVM_CAP_S390_PROTECTED_ASYNC_DISABLE 224
> #define KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP 225
>
> +#define KVM_CAP_ARM_RME 300 // FIXME: Large number to prevent conflicts
> +
> #ifdef KVM_CAP_IRQ_ROUTING
>
> struct kvm_irq_routing_irqchip {