[PATCH v3 09/18] x86/virt: KVM: Open code cpu_has_vmx() in KVM VMX

Sean Christopherson
2023-05-12T23:51:50Z

Fold the raw CPUID check for VMX into kvm_is_vmx_supported(), its sole
user. Keep the check even though KVM also checks X86_FEATURE_VMX, as the
intent is to provide a unique error message if VMX is unsupported by
hardware, whereas X86_FEATURE_VMX may be clear due to firmware and/or
kernel actions.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/include/asm/virtext.h | 10 ----------
arch/x86/kvm/vmx/vmx.c | 2 +-
2 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h
index aaed66249ccf..b1171a5ad452 100644
--- a/arch/x86/include/asm/virtext.h
+++ b/arch/x86/include/asm/virtext.h
@@ -22,14 +22,6 @@
/*
* VMX functions:
*/
-
-static inline int cpu_has_vmx(void)
-{
- unsigned long ecx = cpuid_ecx(1);
- return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */
-}
-
-
/**
* cpu_vmxoff() - Disable VMX on the current CPU
*
@@ -61,8 +53,6 @@ static inline int cpu_vmx_enabled(void)
}

/** Disable VMX if it is enabled on the current CPU
- *
- * You shouldn't call this if cpu_has_vmx() returns 0.
*/
static inline void __cpu_emergency_vmxoff(void)
{
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 76cdb189f1b5..f44f93772b4f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2721,7 +2721,7 @@ static bool kvm_is_vmx_supported(void)
{
int cpu = raw_smp_processor_id();

- if (!cpu_has_vmx()) {
+ if (!(cpuid_ecx(1) & feature_bit(VMX))) {
pr_err("VMX not supported by CPU %d\n", cpu);
return false;
}
--
2.40.1.606.ga4b1b128d6-goog