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Diffstat (limited to 'arch/x86/kvm/cpuid.h')
-rw-r--r--arch/x86/kvm/cpuid.h42
1 files changed, 37 insertions, 5 deletions
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 67d80aa72d50..d3f5ae15a7ca 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -11,11 +11,34 @@ extern u32 kvm_cpu_caps[NR_KVM_CPU_CAPS] __read_mostly;
void kvm_set_cpu_caps(void);
void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu);
-void kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu);
-struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
- u32 function, u32 index);
-struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
- u32 function);
+struct kvm_cpuid_entry2 *kvm_find_cpuid_entry2(struct kvm_cpuid_entry2 *entries,
+ int nent, u32 function, u64 index);
+/*
+ * Magic value used by KVM when querying userspace-provided CPUID entries and
+ * doesn't care about the CPIUD index because the index of the function in
+ * question is not significant. Note, this magic value must have at least one
+ * bit set in bits[63:32] and must be consumed as a u64 by kvm_find_cpuid_entry2()
+ * to avoid false positives when processing guest CPUID input.
+ *
+ * KVM_CPUID_INDEX_NOT_SIGNIFICANT should never be used directly outside of
+ * kvm_find_cpuid_entry2() and kvm_find_cpuid_entry().
+ */
+#define KVM_CPUID_INDEX_NOT_SIGNIFICANT -1ull
+
+static inline struct kvm_cpuid_entry2 *kvm_find_cpuid_entry_index(struct kvm_vcpu *vcpu,
+ u32 function, u32 index)
+{
+ return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
+ function, index);
+}
+
+static inline struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu,
+ u32 function)
+{
+ return kvm_find_cpuid_entry2(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent,
+ function, KVM_CPUID_INDEX_NOT_SIGNIFICANT);
+}
+
int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
struct kvm_cpuid_entry2 __user *entries,
unsigned int type);
@@ -35,6 +58,7 @@ void __init kvm_init_xstate_sizes(void);
u32 xstate_required_size(u64 xstate_bv, bool compacted);
int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu);
+int cpuid_query_maxguestphyaddr(struct kvm_vcpu *vcpu);
u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu);
static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
@@ -232,6 +256,14 @@ static __always_inline bool guest_cpu_cap_has(struct kvm_vcpu *vcpu,
{
unsigned int x86_leaf = __feature_leaf(x86_feature);
+ /*
+ * Except for MWAIT, querying dynamic feature bits is disallowed, so
+ * that KVM can defer runtime updates until the next CPUID emulation.
+ */
+ BUILD_BUG_ON(x86_feature == X86_FEATURE_APIC ||
+ x86_feature == X86_FEATURE_OSXSAVE ||
+ x86_feature == X86_FEATURE_OSPKE);
+
return vcpu->arch.cpu_caps[x86_leaf] & __feature_bit(x86_feature);
}