[PATCH v5 3/6] KVM: x86: Rework kvm_x86_ops.vcpu_pre_run() into .vcpu_needs_initialization()

Rework .vcpu_pre_run() into a more specific .vcpu_needs_initialization() to
consolidate the SNP and TDX control flows, and to eliminate the potentially
confusing almost-collision between svm_vcpu_pre_run() and pre_sev_run(): the
former is SEV specific, but is pre-KVM_RUN, whereas the latter is pre-VMRUN.

Signed-off-by: Sean Christopherson <[email protected]>
---
 arch/x86/include/asm/kvm-x86-ops.h |  2 +-
 arch/x86/include/asm/kvm_host.h    |  2 +-
 arch/x86/kvm/svm/sev.c             |  5 +++++
 arch/x86/kvm/svm/svm.c             | 12 +-----------
 arch/x86/kvm/svm/svm.h             |  1 +
 arch/x86/kvm/vmx/main.c            | 10 ++++------
 arch/x86/kvm/vmx/tdx.c             |  9 +++------
 arch/x86/kvm/vmx/vmx.c             |  5 -----
 arch/x86/kvm/vmx/x86_ops.h         |  3 +--
 arch/x86/kvm/x86.c                 |  5 ++++-
 10 files changed, 21 insertions(+), 33 deletions(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e5b0458afc25..e213c9ae3e30 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -63,7 +63,7 @@ KVM_X86_OP_OPTIONAL(flush_remote_tlbs_range)
 #endif
 KVM_X86_OP(flush_tlb_gva)
 KVM_X86_OP(flush_tlb_guest)
-KVM_X86_OP(vcpu_pre_run)
+KVM_X86_OP_OPTIONAL_RET0(vcpu_needs_initialization)
 KVM_X86_OP(vcpu_run)
 KVM_X86_OP(handle_exit)
 KVM_X86_OP(skip_emulated_instruction)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7e3cacb2df9b..283847619ff8 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1586,7 +1586,7 @@ struct kvm_x86_ops {
 	 */
 	void (*flush_tlb_guest)(struct kvm_vcpu *vcpu);
 
-	int (*vcpu_pre_run)(struct kvm_vcpu *vcpu);
+	bool (*vcpu_needs_initialization)(struct kvm_vcpu *vcpu);
 	enum exit_fastpath_completion (*vcpu_run)(struct kvm_vcpu *vcpu,
 						  u64 run_flags);
 	int (*handle_exit)(struct kvm_vcpu *vcpu,
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 90a08d36d843..fcb41dfde4c0 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3556,6 +3556,11 @@ void sev_free_vcpu(struct kvm_vcpu *vcpu)
 	__sev_es_unmap_ghcb(svm);
 }
 
+bool sev_vcpu_needs_initialization(struct kvm_vcpu *vcpu)
+{
+	return to_kvm_sev_info(vcpu->kvm)->need_init;
+}
+
 int pre_sev_run(struct vcpu_svm *svm, int cpu)
 {
 	struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c1e6d62512b9..9d607b98bd06 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4400,16 +4400,6 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu)
 	svm_complete_interrupts(vcpu);
 }
 
-static int svm_vcpu_pre_run(struct kvm_vcpu *vcpu)
-{
-#ifdef CONFIG_KVM_AMD_SEV
-	if (to_kvm_sev_info(vcpu->kvm)->need_init)
-		return -EINVAL;
-#endif
-
-	return 1;
-}
-
 static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -5376,7 +5366,6 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 	.flush_tlb_gva = svm_flush_tlb_gva,
 	.flush_tlb_guest = svm_flush_tlb_guest,
 
-	.vcpu_pre_run = svm_vcpu_pre_run,
 	.vcpu_run = svm_vcpu_run,
 	.handle_exit = svm_handle_exit,
 	.skip_emulated_instruction = svm_skip_emulated_instruction,
@@ -5434,6 +5423,7 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 #endif
 
 #ifdef CONFIG_KVM_AMD_SEV
+	.vcpu_needs_initialization = sev_vcpu_needs_initialization,
 	.dev_get_attr = sev_dev_get_attr,
 	.mem_enc_ioctl = sev_mem_enc_ioctl,
 	.mem_enc_register_region = sev_mem_enc_register_region,
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index a327bf751ecd..66b44b54608e 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -979,6 +979,7 @@ void sev_es_prepare_switch_to_guest(struct vcpu_svm *svm, struct sev_es_save_are
 void sev_es_unmap_ghcb(struct vcpu_svm *svm);
 
 #ifdef CONFIG_KVM_AMD_SEV
+bool sev_vcpu_needs_initialization(struct kvm_vcpu *vcpu);
 int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp);
 int sev_mem_enc_register_region(struct kvm *kvm,
 				struct kvm_enc_region *range);
diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 2a69dc3ac690..0ff3230fd95e 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -140,12 +140,10 @@ static void vt_vcpu_put(struct kvm_vcpu *vcpu)
 	vmx_vcpu_put(vcpu);
 }
 
-static int vt_vcpu_pre_run(struct kvm_vcpu *vcpu)
+static bool vt_vcpu_needs_initialization(struct kvm_vcpu *vcpu)
 {
-	if (is_td_vcpu(vcpu))
-		return tdx_vcpu_pre_run(vcpu);
-
-	return vmx_vcpu_pre_run(vcpu);
+	return is_td_vcpu(vcpu) &&
+	       tdx_vcpu_needs_initialization(vcpu);
 }
 
 static fastpath_t vt_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags)
@@ -949,7 +947,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
 	.flush_tlb_gva = vt_op(flush_tlb_gva),
 	.flush_tlb_guest = vt_op(flush_tlb_guest),
 
-	.vcpu_pre_run = vt_op(vcpu_pre_run),
+	.vcpu_needs_initialization = vt_op_tdx_only(vcpu_needs_initialization),
 	.vcpu_run = vt_op(vcpu_run),
 	.handle_exit = vt_op(handle_exit),
 	.skip_emulated_instruction = vmx_skip_emulated_instruction,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index d1af0a752e97..b272c20586a7 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -897,13 +897,10 @@ void tdx_vcpu_free(struct kvm_vcpu *vcpu)
 	tdx->state = VCPU_TD_STATE_UNINITIALIZED;
 }
 
-int tdx_vcpu_pre_run(struct kvm_vcpu *vcpu)
+bool tdx_vcpu_needs_initialization(struct kvm_vcpu *vcpu)
 {
-	if (unlikely(to_tdx(vcpu)->state != VCPU_TD_STATE_INITIALIZED ||
-		     to_kvm_tdx(vcpu->kvm)->state != TD_STATE_RUNNABLE))
-		return -EINVAL;
-
-	return 1;
+	return to_tdx(vcpu)->state != VCPU_TD_STATE_INITIALIZED ||
+	       to_kvm_tdx(vcpu->kvm)->state != TD_STATE_RUNNABLE;
 }
 
 static __always_inline u32 tdcall_to_vmx_exit_reason(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 2337b7ede290..76160adf8297 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6110,11 +6110,6 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
 	return 1;
 }
 
-int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu)
-{
-	return 1;
-}
-
 /*
  * Indicate a busy-waiting vcpu in spinlock. We do not enable the PAUSE
  * exiting, so only get here on cpu with PAUSE-Loop-Exiting.
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 551b4195bc1b..cdb38d940cfb 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -21,7 +21,6 @@ int vmx_vm_init(struct kvm *kvm);
 void vmx_vm_destroy(struct kvm *kvm);
 int vmx_vcpu_precreate(struct kvm *kvm);
 int vmx_vcpu_create(struct kvm_vcpu *vcpu);
-int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu);
 fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags);
 void vmx_vcpu_free(struct kvm_vcpu *vcpu);
 void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
@@ -138,7 +137,7 @@ int tdx_vcpu_create(struct kvm_vcpu *vcpu);
 void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
 void tdx_vcpu_free(struct kvm_vcpu *vcpu);
 void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
-int tdx_vcpu_pre_run(struct kvm_vcpu *vcpu);
+bool tdx_vcpu_needs_initialization(struct kvm_vcpu *vcpu);
 fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags);
 void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
 void tdx_vcpu_put(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 64a13acc37be..d94b59140c45 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8867,12 +8867,15 @@ static int kvm_x86_vcpu_pre_run(struct kvm_vcpu *vcpu)
 	    !kvm_apic_init_sipi_allowed(vcpu))
 		return -EINVAL;
 
+	if (kvm_x86_call(vcpu_needs_initialization)(vcpu))
+		return -EINVAL;
+
 	if (kvm_x86_call(unhandleable_emulation_required)(vcpu)) {
 		kvm_prepare_emulation_failure_exit(vcpu);
 		return 0;
 	}
 
-	return kvm_x86_call(vcpu_pre_run)(vcpu);
+	return 1;
 }
 
 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
-- 
2.55.0.508.g3f0d502094-goog