Commit 8721f5b0 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86: Add a helper to check kernel support when setting cpu cap 



Add a helper, kvm_cpu_cap_check_and_set(), to query boot_cpu_has() as
part of setting a KVM cpu capability.  VMX in particular has a number of
features that are dependent on both a VMCS capability and kernel
support.

No functional change intended.

Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent b3d895d5

arch/x86/kvm/cpuid.h

+6 −0
Original line number Diff line number Diff line
@@ -282,4 +282,10 @@ static __always_inline void kvm_cpu_cap_set(unsigned int x86_feature) 
	kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature);

}



static __always_inline void kvm_cpu_cap_check_and_set(unsigned int x86_feature)

{

	if (boot_cpu_has(x86_feature))

		kvm_cpu_cap_set(x86_feature);

}



#endif

arch/x86/kvm/svm.c

+1 −2
Original line number Diff line number Diff line
@@ -1377,8 +1377,7 @@ static __init void svm_set_cpu_caps(void) 


	/* CPUID 0x8000000A */

	/* Support next_rip if host supports it */

	if (boot_cpu_has(X86_FEATURE_NRIPS))

		kvm_cpu_cap_set(X86_FEATURE_NRIPS);

	kvm_cpu_cap_check_and_set(X86_FEATURE_NRIPS);



	if (npt_enabled)

		kvm_cpu_cap_set(X86_FEATURE_NPT);

arch/x86/kvm/vmx/vmx.c

+8 −10
Original line number Diff line number Diff line
@@ -7149,18 +7149,16 @@ static __init void vmx_set_cpu_caps(void) 
		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);

	if (kvm_mpx_supported())

		kvm_cpu_cap_check_and_set(X86_FEATURE_MPX);

	if (cpu_has_vmx_invpcid())

		kvm_cpu_cap_check_and_set(X86_FEATURE_INVPCID);

	if (vmx_pt_mode_is_host_guest())

		kvm_cpu_cap_check_and_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);

	if (enable_ept && boot_cpu_has(X86_FEATURE_OSPKE))

		kvm_cpu_cap_check_and_set(X86_FEATURE_PKU);



	/* CPUID 0xD.1 */

	if (!vmx_xsaves_supported())

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