[RFC,20/67] KVM: x86: Make KVM_CAP_X86_SMM a per-VM capability

Commit Message

Isaku Yamahata Nov. 16, 2020, 6:26 p.m. UTC

From: Isaku Yamahata <[e-mail]>

TDX doesn't support SMM, whereas VMX conditionally support SMM.  Rework
kvm_x86_ops.has_emulated_msr() to take a struct kvm so that TDX can
reject SMM by way of the MSR_IA32_SMBASE check.

This pair with a QEMU change to query SMM support using a VM ioctl().

Signed-off-by: Isaku Yamahata <[e-mail]>
Co-developed-by: Sean Christopherson <[e-mail]>
Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/x86/include/asm/kvm_host.h | 2 +-
 arch/x86/kvm/svm/svm.c          | 2 +-
 arch/x86/kvm/vmx/vmx.c          | 2 +-
 arch/x86/kvm/x86.c              | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 70528102d865..00b34d8f038b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1092,7 +1092,7 @@  struct kvm_x86_ops {
 	void (*hardware_disable)(void);
 	void (*hardware_unsetup)(void);
 	bool (*cpu_has_accelerated_tpr)(void);
-	bool (*has_emulated_msr)(u32 index);
+	bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
 	void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
 
 	bool (*is_vm_type_supported)(unsigned long vm_type);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 11ab330a9b55..241a26e1fa71 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3720,7 +3720,7 @@  static bool svm_cpu_has_accelerated_tpr(void)
 	return false;
 }
 
-static bool svm_has_emulated_msr(u32 index)
+static bool svm_has_emulated_msr(struct kvm *kvm, u32 index)
 {
 	switch (index) {
 	case MSR_IA32_MCG_EXT_CTL:
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b3ecdb96789a..2ee7eb7dac26 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6405,7 +6405,7 @@  static void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu)
 		handle_exception_nmi_irqoff(vmx);
 }
 
-static bool vmx_has_emulated_msr(u32 index)
+static bool vmx_has_emulated_msr(struct kvm *kvm, u32 index)
 {
 	switch (index) {
 	case MSR_IA32_SMBASE:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2fb0d20c5788..2f4b226d5b89 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3726,7 +3726,7 @@  int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		 * fringe case that is not enabled except via specific settings
 		 * of the module parameters.
 		 */
-		r = kvm_x86_ops.has_emulated_msr(MSR_IA32_SMBASE);
+		r = kvm_x86_ops.has_emulated_msr(kvm, MSR_IA32_SMBASE);
 		break;
 	case KVM_CAP_VAPIC:
 		r = !kvm_x86_ops.cpu_has_accelerated_tpr();
@@ -5783,7 +5783,7 @@  static void kvm_init_msr_list(void)
 	}
 
 	for (i = 0; i < ARRAY_SIZE(emulated_msrs_all); i++) {
-		if (!kvm_x86_ops.has_emulated_msr(emulated_msrs_all[i]))
+		if (!kvm_x86_ops.has_emulated_msr(NULL, emulated_msrs_all[i]))
 			continue;
 
 		emulated_msrs[num_emulated_msrs++] = emulated_msrs_all[i];