From: Isaku Yamahata <isaku.yamahata@intel.com>
TD guest vcpu needs TDX specific initialization before running. Repurpose
KVM_MEMORY_ENCRYPT_OP to vcpu-scope, add a new sub-command
KVM_TDX_INIT_VCPU, and implement the callback for it.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Co-developed-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Signed-off-by: Tony Lindgren <tony.lindgren@linux.intel.com>
Co-developed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
uAPI breakout v2:
- Drop dummy tdx_vcpu_reset() (Binbin)
- Calculate nr_vcpu_tcds_pages on init (Nikolay)
- Use vcpu_tdcx naming instead of just tdcx (Yuan)
- No need for is_td_vcpu_created() (Rick)
- No need for is_td_finalized() (Rick)
- Export functions used (Binbin)
- Fixup SEAMCALL call sites due to function parameter changes to SEAMCALL
wrappers (Kai)
- Add TD state handling (Tony)
- Clarify comment wrt is_hkid_assigned() in tdx_vcpu_free() (Yuan)
- Fix error paths in tdx_td_vcpu_init() (Yuan)
- Do not unnecessarily leak tdx->tdvpr_pa in tdx_vcpu_free() (Yuan)
uAPI breakout v1:
- Support FEATURES0_TOPOLOGY_ENUM
- Update for the wrapper functions for SEAMCALLs. (Sean)
- Remove WARN_ON_ONCE() in tdx_vcpu_free().
WARN_ON_ONCE(vcpu->cpu != -1), WARN_ON_ONCE(tdx->tdvpx_pa),
WARN_ON_ONCE(tdx->tdvpr_pa)
- Remove KVM_BUG_ON() in tdx_vcpu_reset().
- Remove duplicate "tdx->tdvpr_pa=" lines
- Rename tdvpx to tdcx as it is confusing, follow spec change for same
reason (Isaku)
- Updates from seamcall overhaul (Kai)
- Rename error->hw_error
- Change using tdx_info to using exported 'tdx_sysinfo' pointer in
tdx_td_vcpu_init().
- Remove code to the old (non-existing) tdx_module_setup().
- Use a new wrapper tdx_sysinfo_nr_tdcx_pages() to replace
tdx_info->nr_tdcx_pages.
- Combine the two for loops in tdx_td_vcpu_init() (Chao)
- Add more line breaks into tdx_td_vcpu_init() for readability (Tony)
- Drop Drop local tdcx_pa in tdx_td_vcpu_init() (Rick)
- Drop Drop local tdvpr_pa in tdx_td_vcpu_init() (Rick)
v18:
- Use tdh_sys_rd() instead of struct tdsysinfo_struct.
- Rename tdx_reclaim_td_page() => tdx_reclaim_control_page()
- Remove the change of tools/arch/x86/include/uapi/asm/kvm.h.
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/include/uapi/asm/kvm.h | 1 +
arch/x86/kvm/vmx/main.c | 9 ++
arch/x86/kvm/vmx/tdx.c | 182 ++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 13 ++-
arch/x86/kvm/vmx/tdx_arch.h | 2 +
arch/x86/kvm/vmx/x86_ops.h | 4 +
arch/x86/kvm/x86.c | 8 ++
9 files changed, 219 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e7bd7867cb94..ec1b1b39c6b3 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -125,6 +125,7 @@ KVM_X86_OP(enable_smi_window)
#endif
KVM_X86_OP_OPTIONAL(dev_get_attr)
KVM_X86_OP(mem_enc_ioctl)
+KVM_X86_OP_OPTIONAL(vcpu_mem_enc_ioctl)
KVM_X86_OP_OPTIONAL(mem_enc_register_region)
KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
KVM_X86_OP_OPTIONAL(vm_copy_enc_context_from)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d8478e103f07..dfa89a5d15ef 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1827,6 +1827,7 @@ struct kvm_x86_ops {
int (*dev_get_attr)(u32 group, u64 attr, u64 *val);
int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
+ int (*vcpu_mem_enc_ioctl)(struct kvm_vcpu *vcpu, void __user *argp);
int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
int (*mem_enc_unregister_region)(struct kvm *kvm, struct kvm_enc_region *argp);
int (*vm_copy_enc_context_from)(struct kvm *kvm, unsigned int source_fd);
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 892e16bd7430..2cfec4b42b9d 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -930,6 +930,7 @@ struct kvm_hyperv_eventfd {
enum kvm_tdx_cmd_id {
KVM_TDX_CAPABILITIES = 0,
KVM_TDX_INIT_VM,
+ KVM_TDX_INIT_VCPU,
KVM_TDX_CMD_NR_MAX,
};
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 0548d54eb055..d28ffddd766f 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -106,6 +106,14 @@ static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
return tdx_vm_ioctl(kvm, argp);
}
+static int vt_vcpu_mem_enc_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
+{
+ if (!is_td_vcpu(vcpu))
+ return -EINVAL;
+
+ return tdx_vcpu_ioctl(vcpu, argp);
+}
+
#define VMX_REQUIRED_APICV_INHIBITS \
(BIT(APICV_INHIBIT_REASON_DISABLED) | \
BIT(APICV_INHIBIT_REASON_ABSENT) | \
@@ -260,6 +268,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
.get_untagged_addr = vmx_get_untagged_addr,
.mem_enc_ioctl = vt_mem_enc_ioctl,
+ .vcpu_mem_enc_ioctl = vt_vcpu_mem_enc_ioctl,
};
struct kvm_x86_init_ops vt_init_ops __initdata = {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 479ffb8f41c8..9008db6cf3b4 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -419,6 +419,7 @@ int tdx_vm_init(struct kvm *kvm)
int tdx_vcpu_create(struct kvm_vcpu *vcpu)
{
struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
if (kvm_tdx->state != TD_STATE_INITIALIZED)
return -EIO;
@@ -442,12 +443,42 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu)
if ((kvm_tdx->xfam & XFEATURE_MASK_XTILE) == XFEATURE_MASK_XTILE)
vcpu->arch.xfd_no_write_intercept = true;
+ tdx->state = VCPU_TD_STATE_UNINITIALIZED;
+
return 0;
}
void tdx_vcpu_free(struct kvm_vcpu *vcpu)
{
- /* This is stub for now. More logic will come. */
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ int i;
+
+ /*
+ * It is not possible to reclaim pages while hkid is assigned. It might
+ * be assigned if:
+ * 1. the TD VM is being destroyed but freeing hkid failed, in which
+ * case the pages are leaked
+ * 2. TD VCPU creation failed and this on the error path, in which case
+ * there is nothing to do anyway
+ */
+ if (is_hkid_assigned(kvm_tdx))
+ return;
+
+ if (tdx->tdcx_pa) {
+ for (i = 0; i < kvm_tdx->nr_vcpu_tdcx_pages; i++) {
+ if (tdx->tdcx_pa[i])
+ tdx_reclaim_control_page(tdx->tdcx_pa[i]);
+ }
+ kfree(tdx->tdcx_pa);
+ tdx->tdcx_pa = NULL;
+ }
+ if (tdx->tdvpr_pa) {
+ tdx_reclaim_control_page(tdx->tdvpr_pa);
+ tdx->tdvpr_pa = 0;
+ }
+
+ tdx->state = VCPU_TD_STATE_UNINITIALIZED;
}
static int tdx_get_capabilities(struct kvm_tdx_cmd *cmd)
@@ -657,6 +688,9 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params *td_params,
tdr_pa = __pa(va);
kvm_tdx->nr_tdcs_pages = tdx_sysinfo->td_ctrl.tdcs_base_size / PAGE_SIZE;
+ /* TDVPS = TDVPR(4K page) + TDCX(multiple 4K pages), -1 for TDVPR. */
+ kvm_tdx->nr_vcpu_tdcx_pages = tdx_sysinfo->td_ctrl.tdvps_base_size / PAGE_SIZE - 1;
+
tdcs_pa = kcalloc(kvm_tdx->nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
GFP_KERNEL_ACCOUNT | __GFP_ZERO);
if (!tdcs_pa)
@@ -936,6 +970,152 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
return r;
}
+/* VMM can pass one 64bit auxiliary data to vcpu via RCX for guest BIOS. */
+static int tdx_td_vcpu_init(struct kvm_vcpu *vcpu, u64 vcpu_rcx)
+{
+ const struct tdx_sys_info_features *modinfo = &tdx_sysinfo->features;
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ unsigned long va;
+ int ret, i;
+ u64 err;
+
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va)
+ return -ENOMEM;
+ tdx->tdvpr_pa = __pa(va);
+
+ tdx->tdcx_pa = kcalloc(kvm_tdx->nr_vcpu_tdcx_pages, sizeof(*tdx->tdcx_pa),
+ GFP_KERNEL_ACCOUNT);
+ if (!tdx->tdcx_pa) {
+ ret = -ENOMEM;
+ goto free_tdvpr;
+ }
+
+ for (i = 0; i < kvm_tdx->nr_vcpu_tdcx_pages; i++) {
+ va = __get_free_page(GFP_KERNEL_ACCOUNT);
+ if (!va) {
+ ret = -ENOMEM;
+ goto free_tdcx;
+ }
+ tdx->tdcx_pa[i] = __pa(va);
+ }
+
+ err = tdh_vp_create(kvm_tdx->tdr_pa, tdx->tdvpr_pa);
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ ret = -EIO;
+ pr_tdx_error(TDH_VP_CREATE, err);
+ goto free_tdcx;
+ }
+
+ for (i = 0; i < kvm_tdx->nr_vcpu_tdcx_pages; i++) {
+ err = tdh_vp_addcx(tdx->tdvpr_pa, tdx->tdcx_pa[i]);
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ pr_tdx_error(TDH_VP_ADDCX, err);
+ /*
+ * Pages already added are reclaimed by the vcpu_free
+ * method, but the rest are freed here.
+ */
+ for (; i < kvm_tdx->nr_vcpu_tdcx_pages; i++) {
+ free_page((unsigned long)__va(tdx->tdcx_pa[i]));
+ tdx->tdcx_pa[i] = 0;
+ }
+ return -EIO;
+ }
+ }
+
+ if (modinfo->tdx_features0 & MD_FIELD_ID_FEATURES0_TOPOLOGY_ENUM)
+ err = tdh_vp_init_apicid(tdx->tdvpr_pa, vcpu_rcx, vcpu->vcpu_id);
+ else
+ err = tdh_vp_init(tdx->tdvpr_pa, vcpu_rcx);
+
+ if (KVM_BUG_ON(err, vcpu->kvm)) {
+ pr_tdx_error(TDH_VP_INIT, err);
+ return -EIO;
+ }
+
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
+
+ return 0;
+
+free_tdcx:
+ for (i = 0; i < kvm_tdx->nr_vcpu_tdcx_pages; i++) {
+ if (tdx->tdcx_pa[i])
+ free_page((unsigned long)__va(tdx->tdcx_pa[i]));
+ tdx->tdcx_pa[i] = 0;
+ }
+ kfree(tdx->tdcx_pa);
+ tdx->tdcx_pa = NULL;
+
+free_tdvpr:
+ if (tdx->tdvpr_pa)
+ free_page((unsigned long)__va(tdx->tdvpr_pa));
+ tdx->tdvpr_pa = 0;
+
+ return ret;
+}
+
+static int tdx_vcpu_init(struct kvm_vcpu *vcpu, struct kvm_tdx_cmd *cmd)
+{
+ struct msr_data apic_base_msr;
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+ int ret;
+
+ if (cmd->flags)
+ return -EINVAL;
+
+ if (tdx->state != VCPU_TD_STATE_UNINITIALIZED)
+ return -EINVAL;
+
+ /*
+ * As TDX requires X2APIC, set local apic mode to X2APIC. User space
+ * VMM, e.g. qemu, is required to set CPUID[0x1].ecx.X2APIC=1 by
+ * KVM_SET_CPUID2. Otherwise kvm_set_apic_base() will fail.
+ */
+ apic_base_msr = (struct msr_data) {
+ .host_initiated = true,
+ .data = APIC_DEFAULT_PHYS_BASE | LAPIC_MODE_X2APIC |
+ (kvm_vcpu_is_reset_bsp(vcpu) ? MSR_IA32_APICBASE_BSP : 0),
+ };
+ if (kvm_set_apic_base(vcpu, &apic_base_msr))
+ return -EINVAL;
+
+ ret = tdx_td_vcpu_init(vcpu, (u64)cmd->data);
+ if (ret)
+ return ret;
+
+ tdx->state = VCPU_TD_STATE_INITIALIZED;
+
+ return 0;
+}
+
+int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp)
+{
+ struct kvm_tdx *kvm_tdx = to_kvm_tdx(vcpu->kvm);
+ struct kvm_tdx_cmd cmd;
+ int ret;
+
+ if (!is_hkid_assigned(kvm_tdx) || kvm_tdx->state == TD_STATE_RUNNABLE)
+ return -EINVAL;
+
+ if (copy_from_user(&cmd, argp, sizeof(cmd)))
+ return -EFAULT;
+
+ if (cmd.hw_error)
+ return -EINVAL;
+
+ switch (cmd.id) {
+ case KVM_TDX_INIT_VCPU:
+ ret = tdx_vcpu_init(vcpu, &cmd);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
static int tdx_online_cpu(unsigned int cpu)
{
unsigned long flags;
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 1fcb7c1b078d..1b78a7ea988e 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -27,15 +27,26 @@ struct kvm_tdx {
u64 xfam;
int hkid;
u8 nr_tdcs_pages;
+ u8 nr_vcpu_tdcx_pages;
u64 tsc_offset;
enum kvm_tdx_state state;
};
+/* TDX module vCPU states */
+enum vcpu_tdx_state {
+ VCPU_TD_STATE_UNINITIALIZED = 0,
+ VCPU_TD_STATE_INITIALIZED,
+};
+
struct vcpu_tdx {
struct kvm_vcpu vcpu;
- /* TDX specific members follow. */
+
+ unsigned long tdvpr_pa;
+ unsigned long *tdcx_pa;
+
+ enum vcpu_tdx_state state;
};
static inline bool is_td(struct kvm *kvm)
diff --git a/arch/x86/kvm/vmx/tdx_arch.h b/arch/x86/kvm/vmx/tdx_arch.h
index 84af7666e958..9d41699e66a2 100644
--- a/arch/x86/kvm/vmx/tdx_arch.h
+++ b/arch/x86/kvm/vmx/tdx_arch.h
@@ -155,4 +155,6 @@ struct td_params {
#define TDX_MIN_TSC_FREQUENCY_KHZ (100 * 1000)
#define TDX_MAX_TSC_FREQUENCY_KHZ (10 * 1000 * 1000)
+#define MD_FIELD_ID_FEATURES0_TOPOLOGY_ENUM BIT_ULL(20)
+
#endif /* __KVM_X86_TDX_ARCH_H */
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 107c60ac94f4..4739891858ea 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -127,6 +127,8 @@ int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
+
+int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
#else
static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
@@ -136,6 +138,8 @@ static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOP
static inline int tdx_vcpu_create(struct kvm_vcpu *vcpu) { return -EOPNOTSUPP; }
static inline void tdx_vcpu_free(struct kvm_vcpu *vcpu) {}
+
+static inline int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp) { return -EOPNOTSUPP; }
#endif
#endif /* __KVM_X86_VMX_X86_OPS_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 95a10c7bc507..92de7ebf2cee 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -698,6 +698,7 @@ int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
kvm_recalculate_apic_map(vcpu->kvm);
return 0;
}
+EXPORT_SYMBOL_GPL(kvm_set_apic_base);
/*
* Handle a fault on a hardware virtualization (VMX or SVM) instruction.
@@ -6308,6 +6309,12 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
case KVM_SET_DEVICE_ATTR:
r = kvm_vcpu_ioctl_device_attr(vcpu, ioctl, argp);
break;
+ case KVM_MEMORY_ENCRYPT_OP:
+ r = -ENOTTY;
+ if (!kvm_x86_ops.vcpu_mem_enc_ioctl)
+ goto out;
+ r = kvm_x86_ops.vcpu_mem_enc_ioctl(vcpu, argp);
+ break;
default:
r = -EINVAL;
}
@@ -12663,6 +12670,7 @@ bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
{
return vcpu->kvm->arch.bsp_vcpu_id == vcpu->vcpu_id;
}
+EXPORT_SYMBOL_GPL(kvm_vcpu_is_reset_bsp);
bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
{
--
2.47.0