[PATCH v10 19/27] KVM: x86: Use KVM-governed feature framework to track "SHSTK/IBT enabled"

From: Yang Weijiang <weijiang.yang@intel.com>
To: seanjc@google.com, pbonzini@redhat.com, dave.hansen@intel.com,
	x86@kernel.org, kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: peterz@infradead.org, chao.gao@intel.com,
	rick.p.edgecombe@intel.com, mlevitsk@redhat.com,
	john.allen@amd.com, weijiang.yang@intel.com
Subject: [PATCH v10 19/27] KVM: x86: Use KVM-governed feature framework to track "SHSTK/IBT enabled"
Date: Sun, 18 Feb 2024 23:47:25 -0800	[thread overview]
Message-ID: <20240219074733.122080-20-weijiang.yang@intel.com> (raw)
In-Reply-To: <20240219074733.122080-1-weijiang.yang@intel.com>

Use the governed feature framework to track whether X86_FEATURE_SHSTK
and X86_FEATURE_IBT features can be used by userspace and guest, i.e.,
the features can be used iff both KVM and guest CPUID can support them.

TODO: remove this patch once Sean's refactor to "KVM-governed" framework
is upstreamed. See the work here [*].

[*]: https://lore.kernel.org/all/20231110235528.1561679-1-seanjc@google.com/

Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 arch/x86/kvm/governed_features.h | 2 ++
 arch/x86/kvm/vmx/vmx.c           | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/arch/x86/kvm/governed_features.h b/arch/x86/kvm/governed_features.h
index ad463b1ed4e4..daf0c0a3e29c 100644
--- a/arch/x86/kvm/governed_features.h
+++ b/arch/x86/kvm/governed_features.h
@@ -17,6 +17,8 @@ KVM_GOVERNED_X86_FEATURE(PFTHRESHOLD)
 KVM_GOVERNED_X86_FEATURE(VGIF)
 KVM_GOVERNED_X86_FEATURE(VNMI)
 KVM_GOVERNED_X86_FEATURE(LAM)
+KVM_GOVERNED_X86_FEATURE(SHSTK)
+KVM_GOVERNED_X86_FEATURE(IBT)
 
 #undef KVM_GOVERNED_X86_FEATURE
 #undef KVM_GOVERNED_FEATURE
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 46042bc6e2fa..6cb94754c2a9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7764,6 +7764,8 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
 
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VMX);
 	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_LAM);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_SHSTK);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_IBT);
 
 	vmx_setup_uret_msrs(vmx);
 
-- 
2.43.0

