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Subject[PATCH 43/61] KVM: x86: Use KVM cpu caps to mark CR4.LA57 as not-reserved
Date
Add accessor(s) for KVM cpu caps and use said accessor to detect
hardware support for LA57 instead of manually querying CPUID.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/cpuid.h | 13 +++++++++++++
arch/x86/kvm/x86.c | 2 +-
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 7b71ae0ca05e..5ce4219d465f 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -274,6 +274,19 @@ static __always_inline void kvm_cpu_cap_set(unsigned x86_feature)
kvm_cpu_caps[x86_leaf] |= __feature_bit(x86_feature);
}

+static __always_inline u32 kvm_cpu_cap_get(unsigned x86_feature)
+{
+ unsigned x86_leaf = x86_feature / 32;
+
+ reverse_cpuid_check(x86_leaf);
+ return kvm_cpu_caps[x86_leaf] & __feature_bit(x86_feature);
+}
+
+static __always_inline bool kvm_cpu_cap_has(unsigned x86_feature)
+{
+ return kvm_cpu_cap_get(x86_feature);
+}
+
static __always_inline void kvm_cpu_cap_check_and_set(unsigned x86_feature)
{
if (boot_cpu_has(x86_feature))
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c5ed199d6cd9..cb40737187a1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -912,7 +912,7 @@ static u64 kvm_host_cr4_reserved_bits(struct cpuinfo_x86 *c)
{
u64 reserved_bits = __cr4_reserved_bits(cpu_has, c);

- if (cpuid_ecx(0x7) & feature_bit(LA57))
+ if (kvm_cpu_cap_has(X86_FEATURE_LA57))
reserved_bits &= ~X86_CR4_LA57;

if (kvm_x86_ops->umip_emulated())
--
2.24.1
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