[PATCH v2 40/66] KVM: VMX: Convert feature updates from CPUID to KVM cpu caps

Sean Christopherson
2020-03-02T23:58:40Z

Use the recently introduced KVM CPU caps to propagate VMX-only (kernel)
settings to supported CPUID flags.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/vmx/vmx.c | 56 +++++++++++++++++++++++++-----------------
1 file changed, 34 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 131f4b88d307..6f68d5e694e0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7119,40 +7119,50 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
}
}

+/*
+ * Vendor specific emulation must be handled via ->set_supported_cpuid(), not
+ * vmx_set_cpu_caps(), as capabilities configured during hardware_setup() are
+ * masked against hardware/kernel support, i.e. they'd be lost.
+ */
static void vmx_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
{
switch (entry->function) {
- case 0x1:
- if (nested)
- cpuid_entry_set(entry, X86_FEATURE_VMX);
- break;
case 0x7:
- if (boot_cpu_has(X86_FEATURE_MPX) && kvm_mpx_supported())
- cpuid_entry_set(entry, X86_FEATURE_MPX);
- if (boot_cpu_has(X86_FEATURE_INVPCID) && cpu_has_vmx_invpcid())
- cpuid_entry_set(entry, X86_FEATURE_INVPCID);
- if (boot_cpu_has(X86_FEATURE_INTEL_PT) &&
- vmx_pt_mode_is_host_guest())
- cpuid_entry_set(entry, X86_FEATURE_INTEL_PT);
if (vmx_umip_emulated())
cpuid_entry_set(entry, X86_FEATURE_UMIP);
-
- /* PKU is not yet implemented for shadow paging. */
- if (enable_ept && boot_cpu_has(X86_FEATURE_PKU) &&
- boot_cpu_has(X86_FEATURE_OSPKE))
- cpuid_entry_set(entry, X86_FEATURE_PKU);
- break;
- case 0x80000001:
- if (!cpu_has_vmx_rdtscp())
- cpuid_entry_clear(entry, X86_FEATURE_RDTSCP);
- if (enable_ept && !cpu_has_vmx_ept_1g_page())
- cpuid_entry_clear(entry, X86_FEATURE_GBPAGES);
break;
default:
break;
}
}

+static __init void vmx_set_cpu_caps(void)
+{
+ /* CPUID 0x1 */
+ if (nested)
+ kvm_cpu_cap_set(X86_FEATURE_VMX);
+
+ /* CPUID 0x7 */
+ if (boot_cpu_has(X86_FEATURE_MPX) && kvm_mpx_supported())
+ kvm_cpu_cap_set(X86_FEATURE_MPX);
+ if (boot_cpu_has(X86_FEATURE_INVPCID) && cpu_has_vmx_invpcid())
+ kvm_cpu_cap_set(X86_FEATURE_INVPCID);
+ if (boot_cpu_has(X86_FEATURE_INTEL_PT) &&
+ vmx_pt_mode_is_host_guest())
+ kvm_cpu_cap_set(X86_FEATURE_INTEL_PT);
+
+ /* PKU is not yet implemented for shadow paging. */
+ if (enable_ept && boot_cpu_has(X86_FEATURE_PKU) &&
+ boot_cpu_has(X86_FEATURE_OSPKE))
+ kvm_cpu_cap_set(X86_FEATURE_PKU);
+
+ /* CPUID 0x80000001 */
+ if (!cpu_has_vmx_rdtscp())
+ kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
+ if (enable_ept && !cpu_has_vmx_ept_1g_page())
+ kvm_cpu_cap_clear(X86_FEATURE_GBPAGES);
+}
+
static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
{
to_vmx(vcpu)->req_immediate_exit = true;
@@ -7815,6 +7825,8 @@ static __init int hardware_setup(void)
return r;
}

+ vmx_set_cpu_caps();
+
r = alloc_kvm_area();
if (r)
nested_vmx_hardware_unsetup();
--
2.24.1