[PATCH 2/6] KVM: X86: Go on updating other CPUID leaves when leaf 1 is absent

From: Xiaoyao Li
Date: Fri May 29 2020 - 04:55:58 EST


As handling of bits other leaf 1 added over time, kvm_update_cpuid()
should not return directly if leaf 1 is absent, but should go on
updateing other CPUID leaves.

Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
arch/x86/kvm/cpuid.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 2f1a9650b7f2..795bbaf37110 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -60,22 +60,21 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu)
struct kvm_lapic *apic = vcpu->arch.apic;

best = kvm_find_cpuid_entry(vcpu, 1, 0);
- if (!best)
- return 0;
-
- /* Update OSXSAVE bit */
- if (boot_cpu_has(X86_FEATURE_XSAVE) && best->function == 0x1)
- cpuid_entry_change(best, X86_FEATURE_OSXSAVE,
+ if (best) {
+ /* Update OSXSAVE bit */
+ if (boot_cpu_has(X86_FEATURE_XSAVE))
+ cpuid_entry_change(best, X86_FEATURE_OSXSAVE,
kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE));

- cpuid_entry_change(best, X86_FEATURE_APIC,
+ cpuid_entry_change(best, X86_FEATURE_APIC,
vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE);

- if (apic) {
- if (cpuid_entry_has(best, X86_FEATURE_TSC_DEADLINE_TIMER))
- apic->lapic_timer.timer_mode_mask = 3 << 17;
- else
- apic->lapic_timer.timer_mode_mask = 1 << 17;
+ if (apic) {
+ if (cpuid_entry_has(best, X86_FEATURE_TSC_DEADLINE_TIMER))
+ apic->lapic_timer.timer_mode_mask = 3 << 17;
+ else
+ apic->lapic_timer.timer_mode_mask = 1 << 17;
+ }
}

best = kvm_find_cpuid_entry(vcpu, 7, 0);
--
2.18.2