[PATCH v2 41/66] KVM: x86: Move XSAVES CPUID adjust to VMX's KVM cpu cap update

Sean Christopherson
2020-03-02T23:58:27Z

Move the clearing of the XSAVES CPUID bit into VMX, which has a separate
VMCS control to enable XSAVES in non-root, to eliminate the last ugly
renmant of the undesirable "unsigned f_* = *_supported ? F(*) : 0"
pattern in the common CPUID handling code.

Drop ->xsaves_supported(), CPUID adjustment was the only user.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/include/asm/kvm_host.h | 1 -
arch/x86/kvm/cpuid.c | 4 ----
arch/x86/kvm/svm.c | 6 ------
arch/x86/kvm/vmx/vmx.c | 5 ++++-
4 files changed, 4 insertions(+), 12 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 449695788351..f5b49fa6f066 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1169,7 +1169,6 @@ struct kvm_x86_ops {
void (*handle_exit_irqoff)(struct kvm_vcpu *vcpu,
enum exit_fastpath_completion *exit_fastpath);

- bool (*xsaves_supported)(void);
bool (*umip_emulated)(void);
bool (*pt_supported)(void);

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index e26644d8280b..1c361a65ee03 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -634,10 +634,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
goto out;

cpuid_entry_mask(entry, CPUID_D_1_EAX);
-
- if (!kvm_x86_ops->xsaves_supported())
- cpuid_entry_clear(entry, X86_FEATURE_XSAVES);
-
if (entry->eax & (F(XSAVES)|F(XSAVEC)))
entry->ebx = xstate_required_size(supported_xcr0, true);
else
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 8ce07f6ebe8e..a1317e72824d 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6084,11 +6084,6 @@ static bool svm_rdtscp_supported(void)
return boot_cpu_has(X86_FEATURE_RDTSCP);
}

-static bool svm_xsaves_supported(void)
-{
- return boot_cpu_has(X86_FEATURE_XSAVES);
-}
-
static bool svm_umip_emulated(void)
{
return false;
@@ -7459,7 +7454,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.cpuid_update = svm_cpuid_update,

.rdtscp_supported = svm_rdtscp_supported,
- .xsaves_supported = svm_xsaves_supported,
.umip_emulated = svm_umip_emulated,
.pt_supported = svm_pt_supported,

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6f68d5e694e0..208a40e89a3f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7156,6 +7156,10 @@ static __init void vmx_set_cpu_caps(void)
boot_cpu_has(X86_FEATURE_OSPKE))
kvm_cpu_cap_set(X86_FEATURE_PKU);

+ /* CPUID 0xD.1 */
+ if (!vmx_xsaves_supported())
+ kvm_cpu_cap_clear(X86_FEATURE_XSAVES);
+
/* CPUID 0x80000001 */
if (!cpu_has_vmx_rdtscp())
kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
@@ -7956,7 +7960,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {

.check_intercept = vmx_check_intercept,
.handle_exit_irqoff = vmx_handle_exit_irqoff,
- .xsaves_supported = vmx_xsaves_supported,
.umip_emulated = vmx_umip_emulated,
.pt_supported = vmx_pt_supported,

--
2.24.1