[23/29] KVM: x86: extract kvm_post_set_cpuid

Commit Message

Paolo Bonzini April 1, 2025, 4:11 p.m. UTC

CPU state depends on CPUID info and is initialized by KVM_SET_CPUID2,
but KVM_SET_CPUID2 does not exist for non-default planes.  Instead, they
just copy over the CPUID info of plane 0.

Extract the tail of KVM_SET_CPUID2 so that it can be executed as part
of KVM_CREATE_VCPU_PLANE.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 arch/x86/kvm/cpuid.c | 38 ++++++++++++++++++++++++--------------
 arch/x86/kvm/cpuid.h |  1 +
 2 files changed, 25 insertions(+), 14 deletions(-)

Patch

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index f760a8a5d719..142decb3a736 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -488,6 +488,29 @@  u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu)
 	return rsvd_bits(cpuid_maxphyaddr(vcpu), 63);
 }
 
+int kvm_post_set_cpuid(struct kvm_vcpu *vcpu)
+{
+	int r;
+
+#ifdef CONFIG_KVM_HYPERV
+	if (kvm_cpuid_has_hyperv(vcpu)) {
+		r = kvm_hv_vcpu_init(vcpu);
+		if (r)
+			return r;
+	}
+#endif
+
+	r = kvm_check_cpuid(vcpu);
+	if (r)
+		return r;
+
+#ifdef CONFIG_KVM_XEN
+	vcpu->arch.xen.cpuid = kvm_get_hypervisor_cpuid(vcpu, XEN_SIGNATURE);
+#endif
+	kvm_vcpu_after_set_cpuid(vcpu);
+	return 0;
+}
+
 static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
                         int nent)
 {
@@ -529,23 +552,10 @@  static int kvm_set_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2,
 		goto success;
 	}
 
-#ifdef CONFIG_KVM_HYPERV
-	if (kvm_cpuid_has_hyperv(vcpu)) {
-		r = kvm_hv_vcpu_init(vcpu);
-		if (r)
-			goto err;
-	}
-#endif
-
-	r = kvm_check_cpuid(vcpu);
+	r = kvm_post_set_cpuid(vcpu);
 	if (r)
 		goto err;
 
-#ifdef CONFIG_KVM_XEN
-	vcpu->arch.xen.cpuid = kvm_get_hypervisor_cpuid(vcpu, XEN_SIGNATURE);
-#endif
-	kvm_vcpu_after_set_cpuid(vcpu);
-
 success:
 	kvfree(e2);
 	return 0;
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index d3f5ae15a7ca..05cc1245f570 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -42,6 +42,7 @@  static inline struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcp
 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
 			    struct kvm_cpuid_entry2 __user *entries,
 			    unsigned int type);
+int kvm_post_set_cpuid(struct kvm_vcpu *vcpu);
 int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
 			     struct kvm_cpuid *cpuid,
 			     struct kvm_cpuid_entry __user *entries);